| Transactions |
| Date | Team | Player | Type | OthTm | EffDate | When |
| 4/5/2012 | EMP | Nix,L | Demoted to reserve roster | | | Before |
| 4/5/2012 | EMP | Tekotte | Promoted to active roster | | | Before |
| 4/5/2012 | REB | Carmona | Promoted to active roster | | | Before |
| 4/5/2012 | REB | Crow | Promoted to active roster | | | Before |
| 4/5/2012 | REB | Johnson,Jo | Demoted to reserve roster | | | Before |
| 4/5/2012 | REB | Soriano,R | Demoted to reserve roster | | | Before |
| 4/6/2012 | EAG | Beavan | Demoted to reserve roster | | | Before |
| 4/6/2012 | EAG | Campana | Demoted to reserve roster | | | Before |
| 4/6/2012 | EAG | Capps | Demoted to reserve roster | | | Before |
| 4/6/2012 | EAG | Janish | Demoted to reserve roster | | | Before |
| 4/6/2012 | EAG | Janish | Promoted to active roster | | | Before |
| 4/6/2012 | EAG | Lackey | Demoted to reserve roster | | | Before |
| 4/6/2012 | EAG | Maldonado | Demoted to reserve roster | | | Before |
| 4/6/2012 | EAG | Miley | Demoted to reserve roster | | | Before |
| 4/6/2012 | EAG | Pacheco | Demoted to reserve roster | | | Before |
| 4/6/2012 | EAG | Pauley | Demoted to reserve roster | | | Before |
| 4/6/2012 | EAG | Rodney | Demoted to reserve roster | | | Before |
| 4/6/2012 | EAG | Zimmerman | Demoted to reserve roster | | | Before |
| 4/6/2012 | FOR | Chapman | Demoted to reserve roster | | | Before |
| 4/6/2012 | FOR | Cobb | Demoted to reserve roster | | | Before |
| 4/6/2012 | FOR | Dirks | Promoted to active roster | | | Before |
| 4/6/2012 | FOR | Francisco,J | Demoted to reserve roster | | | Before |
| 4/6/2012 | FOR | Gomez,J | Promoted to active roster | | | Before |
| 4/6/2012 | FOR | Lowe,M | Promoted to active roster | | | Before |
| 4/6/2012 | FOR | Samardzija | Demoted to reserve roster | | | Before |
| 4/6/2012 | FOR | Wilson,Br | Promoted to active roster | | | Before |
| 4/6/2012 | LEG | Frieri | Demoted to reserve roster | | | Before |
| 4/6/2012 | LEG | Gutierrez,J | Promoted to active roster | | | Before |
| 4/6/2012 | LEG | Hand | Demoted to reserve roster | | | Before |
| 4/6/2012 | LEG | Jackson,C | Promoted to active roster | | | Before |
| 4/6/2012 | LEG | Jennings | Demoted to reserve roster | | | Before |
| 4/6/2012 | LEG | Pelfrey | Promoted to active roster | | | Before |
| 4/6/2012 | LEG | Sanchez,J | Demoted to reserve roster | | | Before |
| 4/6/2012 | LEG | Santos,S | Demoted to reserve roster | | | Before |
| 4/6/2012 | LEG | Spence | Promoted to active roster | | | Before |
| 4/6/2012 | LEG | Volstad | Promoted to active roster | | | Before |
| 4/6/2012 | OUT | Delgado | Promoted to active roster | | | Before |
| 4/6/2012 | OUT | Wood,Bl | Demoted to reserve roster | | | Before |
| 4/6/2012 | QUI | Baker,S | Demoted to reserve roster | | | Before |
| 4/6/2012 | QUI | Lyles | Promoted to active roster | | | Before |
| 4/6/2012 | SCO | Castro,R | Demoted to reserve roster | | | Before |
| 4/6/2012 | SCO | Ross,D | Promoted to active roster | | | Before |
| 4/6/2012 | SLG | Bogusevic | Demoted to reserve roster | | | Before |
| 4/6/2012 | SLG | Presley | Promoted to active roster | | | Before |
| 4/6/2012 | SYN | Bowden | Demoted to reserve roster | | | Before |
| 4/6/2012 | SYN | Minor | Promoted to active roster | | | Before |
| 4/6/2012 | SYN | Worley | Promoted to active roster | | | Before |
| 4/6/2012 | SYN | Zambrano | Demoted to reserve roster | | | Before |
| 4/10/2012 | REB | Bedard | Demoted to reserve roster | | | Before |
| 4/10/2012 | REB | Crow | Demoted to reserve roster | | | Before |
| 4/10/2012 | REB | Peavy | Promoted to active roster | | | Before |
| 4/10/2012 | REB | Soriano,R | Promoted to active roster | | | Before |
| 4/11/2012 | EMP | Herrera,K | Promoted to active roster | | | Before |
| 4/11/2012 | EMP | Lavarnway | Demoted to reserve roster | | | Before |
| 4/11/2012 | FOR | Gomez,J | Demoted to reserve roster | | | Before |
| 4/11/2012 | FOR | Kendrick,K | Promoted to active roster | | | Before |
| 4/11/2012 | FOR | Lowe,M | Demoted to reserve roster | | | Before |
| 4/11/2012 | FOR | Willis | Promoted to active roster | | | Before |
| 4/11/2012 | INP | Betances | Demoted to reserve roster | | | Before |
| 4/11/2012 | INP | Markakis | Promoted to active roster | | | Before |
| 4/11/2012 | LEG | Cishek | Demoted to reserve roster | | | Before |
| 4/11/2012 | LEG | Cueto | Promoted to active roster | | | Before |
| 4/11/2012 | LEG | Frieri | Promoted to active roster | | | Before |
| 4/11/2012 | LEG | Gutierrez,J | Demoted to reserve roster | | | Before |
| 4/11/2012 | LEG | Jennings | Promoted to active roster | | | Before |
| 4/11/2012 | LEG | Pelfrey | Demoted to reserve roster | | | Before |
| 4/11/2012 | LEG | Sanchez,J | Promoted to active roster | | | Before |
| 4/11/2012 | LEG | Santos,S | Promoted to active roster | | | Before |
| 4/11/2012 | LEG | Volstad | Demoted to reserve roster | | | Before |
| 4/11/2012 | LEG | Worth | Demoted to reserve roster | | | Before |
| 4/11/2012 | PIN | Arroyo | Demoted to reserve roster | | | Before |
| 4/11/2012 | PIN | Coleman,C | Promoted to active roster | | | Before |
| 4/11/2012 | PIN | Davis,I | Demoted to reserve roster | | | Before |
| 4/11/2012 | PIN | Davis,I | Promoted to active roster | | | Before |
| 4/11/2012 | PIN | Diaz | Demoted to reserve roster | | | Before |
| 4/11/2012 | PIN | Furcal | Promoted to active roster | | | Before |
| 4/11/2012 | PIN | Murphy,Dan | Demoted to reserve roster | | | Before |
| 4/11/2012 | PIN | Paulino,F | Promoted to active roster | | | Before |
| 4/11/2012 | PIN | Reddick | Promoted to active roster | | | Before |
| 4/11/2012 | PIN | Wakefield | Demoted to reserve roster | | | Before |
| 4/11/2012 | REB | Crow | Promoted to active roster | | | Before |
| 4/11/2012 | REB | Soriano,R | Demoted to reserve roster | | | Before |
| 4/11/2012 | SLG | Devine | Promoted to active roster | | | Before |
| 4/11/2012 | SLG | Ibanez | Promoted to active roster | | | Before |
| 4/11/2012 | SLG | Lindstrom | Demoted to reserve roster | | | Before |
| 4/11/2012 | SLG | Lynn | Promoted to active roster | | | Before |
| 4/11/2012 | SLG | Mujica | Demoted to reserve roster | | | Before |
| 4/11/2012 | SLG | Presley | Demoted to reserve roster | | | Before |
| 4/11/2012 | SYN | Bowden | Promoted to active roster | | | Before |
| 4/11/2012 | SYN | Minor | Demoted to reserve roster | | | Before |
| 4/11/2012 | SYN | Worley | Demoted to reserve roster | | | Before |
| 4/11/2012 | SYN | Zambrano | Promoted to active roster | | | Before |
| 4/15/2012 | REB | Carmona | Demoted to reserve roster | | | Before |
| 4/15/2012 | REB | Crow | Demoted to reserve roster | | | Before |
| 4/15/2012 | REB | Johnson,Jo | Promoted to active roster | | | Before |
| 4/15/2012 | REB | Soriano,R | Promoted to active roster | | | Before |
| 4/15/2012 | SKT | Hamilton,J | Demoted to reserve roster | | | Before |
| 4/15/2012 | SKT | Moreland | Demoted to reserve roster | | | Before |
| 4/15/2012 | SKT | Overbay | Promoted to active roster | | | Before |
| 4/15/2012 | SKT | Span | Promoted to active roster | | | Before |
| 4/17/2012 | B C | Belt | Promoted to active roster | | | Before |
| 4/17/2012 | B C | Borbon | Promoted to active roster | | | Before |
| 4/17/2012 | B C | LaPorta | Demoted to reserve roster | | | Before |
| 4/17/2012 | B C | Morel | Demoted to reserve roster | | | Before |
| 4/17/2012 | B C | Morrison | Demoted to reserve roster | | | Before |
| 4/17/2012 | B C | Schafer,J | Promoted to active roster | | | Before |
| 4/17/2012 | B C | Sizemore,S | Demoted to reserve roster | | | Before |
| 4/17/2012 | B C | Volquez | Promoted to active roster | | | Before |
| 4/17/2012 | B C | Young,E | Demoted to reserve roster | | | Before |
| 4/17/2012 | B C | Young,E | Promoted to active roster | | | Before |
| 4/17/2012 | EAG | Janish | Demoted to reserve roster | | | Before |
| 4/17/2012 | EAG | Zimmerman | Promoted to active roster | | | Before |
| 4/17/2012 | EMP | Brach | Demoted to reserve roster | | | Before |
| 4/17/2012 | EMP | Nix,L | Promoted to active roster | | | Before |
| 4/17/2012 | FOR | Dirks | Demoted to reserve roster | | | Before |
| 4/17/2012 | FOR | Francisco,J | Promoted to active roster | | | Before |
| 4/17/2012 | FOR | Paredes | Demoted to reserve roster | | | Before |
| 4/17/2012 | FOR | Paredes | Promoted to active roster | | | Before |
| 4/17/2012 | FOR | Samardzija | Promoted to active roster | | | Before |
| 4/17/2012 | FOR | Willis | Demoted to reserve roster | | | Before |
| 4/17/2012 | LEG | Broxton | Promoted to active roster | | | Before |
| 4/17/2012 | LEG | Cishek | Demoted to reserve roster | | | Before |
| 4/17/2012 | LEG | Cueto | Promoted to active roster | | | Before |
| 4/17/2012 | LEG | Frieri | Promoted to active roster | | | Before |
| 4/17/2012 | LEG | Gutierrez,J | Demoted to reserve roster | | | Before |
| 4/17/2012 | LEG | Hand | Promoted to active roster | | | Before |
| 4/17/2012 | LEG | Jackson,C | Demoted to reserve roster | | | Before |
| 4/17/2012 | LEG | Lee,D | Promoted to active roster | | | Before |
| 4/17/2012 | LEG | Pelfrey | Demoted to reserve roster | | | Before |
| 4/17/2012 | LEG | Pineda | Demoted to reserve roster | | | Before |
| 4/17/2012 | LEG | Sanchez,J | Promoted to active roster | | | Before |
| 4/17/2012 | LEG | Santos,S | Promoted to active roster | | | Before |
| 4/17/2012 | LEG | Spence | Demoted to reserve roster | | | Before |
| 4/17/2012 | LEG | Volstad | Demoted to reserve roster | | | Before |
| 4/17/2012 | PHO | Arredondo | Demoted to reserve roster | | | Before |
| 4/17/2012 | PHO | Colon | Promoted to active roster | | | Before |
| 4/17/2012 | PHO | Hawkins | Promoted to active roster | | | Before |
| 4/17/2012 | PHO | Lewis,C | Demoted to reserve roster | | | Before |
| 4/17/2012 | PIN | Davis,R | Demoted to reserve roster | | | Before |
| 4/17/2012 | PIN | Diaz | Promoted to active roster | | | Before |
| 4/17/2012 | PIN | Furcal | Demoted to reserve roster | | | Before |
| 4/17/2012 | PIN | Lowrie | Promoted to active roster | | | Before |
| 4/17/2012 | PIN | Murphy,Dan | Promoted to active roster | | | Before |
| 4/17/2012 | PIN | Sanchez,F | Demoted to reserve roster | | | Before |
| 4/17/2012 | PIN | Wakefield | Demoted to reserve roster | | | Before |
| 4/17/2012 | PIN | Wakefield | Promoted to active roster | | | Before |
| 4/17/2012 | SCO | Craig | Demoted to reserve roster | | | Before |
| 4/17/2012 | SCO | Sizemore,G | Promoted to active roster | | | Before |
| 4/17/2012 | SID | Davis,W | Promoted to active roster | | | Before |
| 4/17/2012 | SID | Harrison,M | Demoted to reserve roster | | | Before |
| 4/17/2012 | SYN | Bowden | Demoted to reserve roster | | | Before |
| 4/17/2012 | SYN | Minor | Promoted to active roster | | | Before |
| 4/17/2012 | SYN | Worley | Promoted to active roster | | | Before |
| 4/17/2012 | SYN | Zambrano | Demoted to reserve roster | | | Before |
| 4/21/2012 | PIN | Coleman,C | Demoted to reserve roster | | | Before |
| 4/21/2012 | PIN | Davis,I | Demoted to reserve roster | | | Before |
| 4/21/2012 | PIN | Furcal | Promoted to active roster | | | Before |
| 4/21/2012 | PIN | Wakefield | Promoted to active roster | | | Before |
| 4/21/2012 | REB | Carmona | Promoted to active roster | | | Before |
| 4/21/2012 | REB | Crow | Promoted to active roster | | | Before |
| 4/21/2012 | REB | Johnson,Jo | Demoted to reserve roster | | | Before |
| 4/21/2012 | REB | Soriano,R | Demoted to reserve roster | | | Before |
| 4/21/2012 | SLG | Boggs,M | Promoted to active roster | | | Before |
| 4/21/2012 | SLG | Devine | Demoted to reserve roster | | | Before |
| 4/21/2012 | SLG | Lynn | Demoted to reserve roster | | | Before |
| 4/21/2012 | SLG | Mujica | Promoted to active roster | | | Before |
| 4/22/2012 | EAG | Janish | Promoted to active roster | | | Before |
| 4/22/2012 | EAG | Zimmerman | Demoted to reserve roster | | | Before |
| 4/22/2012 | FOR | Cobb | Promoted to active roster | | | Before |
| 4/22/2012 | FOR | Richard | Demoted to reserve roster | | | Before |
| 4/22/2012 | LEG | Cahill | Demoted to reserve roster | | | Before |
| 4/22/2012 | LEG | Hand | Demoted to reserve roster | | | Before |
| 4/22/2012 | LEG | Jennings | Promoted to active roster | | | Before |
| 4/22/2012 | LEG | Pelfrey | Promoted to active roster | | | Before |
| 4/22/2012 | LEG | Pineda | Promoted to active roster | | | Before |
| 4/22/2012 | LEG | Worth | Demoted to reserve roster | | | Before |
| 4/22/2012 | PHO | Colon | Demoted to reserve roster | | | Before |
| 4/22/2012 | PHO | Lewis,C | Promoted to active roster | | | Before |
| 4/22/2012 | SLG | Boggs,M | Demoted to reserve roster | | | Before |
| 4/22/2012 | SLG | Brignac | Promoted to active roster | | | Before |
| 4/22/2012 | SLG | Jurrjens | Demoted to reserve roster | | | Before |
| 4/22/2012 | SLG | Lindstrom | Promoted to active roster | | | Before |
| 4/22/2012 | SLG | Scutaro | Demoted to reserve roster | | | Before |
| 4/22/2012 | SLG | Westbrook | Promoted to active roster | | | Before |
| 4/22/2012 | SYN | Worley | Demoted to reserve roster | | | Before |
| 4/22/2012 | SYN | Zambrano | Promoted to active roster | | | Before |
| 4/26/2012 | REB | Bedard | Promoted to active roster | | | Before |
| 4/26/2012 | REB | Peavy | Demoted to reserve roster | | | Before |
| 4/26/2012 | SKT | Badenhop | Demoted to reserve roster | | | Before |
| 4/26/2012 | SKT | Beato | Promoted to active roster | | | Before |
| 4/26/2012 | SKT | Blackburn | Demoted to reserve roster | | | Before |
| 4/26/2012 | SKT | Blanco,H | Demoted to reserve roster | | | Before |
| 4/26/2012 | SKT | Corporan | Promoted to active roster | | | Before |
| 4/26/2012 | SKT | Damon | Demoted to reserve roster | | | Before |
| 4/26/2012 | SKT | Gregerson | Demoted to reserve roster | | | Before |
| 4/26/2012 | SKT | Hamilton,J | Promoted to active roster | | | Before |
| 4/26/2012 | SKT | Matsui | Promoted to active roster | | | Before |
| 4/26/2012 | SKT | Nicasio | Promoted to active roster | | | Before |
| 4/26/2012 | SKT | Span | Demoted to reserve roster | | | Before |
| 4/26/2012 | SKT | Wright,J | Promoted to active roster | | | Before |
| 4/27/2012 | EMP | Brach | Promoted to active roster | | | Before |
| 4/27/2012 | EMP | Braden | Promoted to active roster | | | Before |
| 4/27/2012 | EMP | Herrera,K | Demoted to reserve roster | | | Before |
| 4/27/2012 | EMP | Ogando | Demoted to reserve roster | | | Before |
| 4/27/2012 | EMP | Reed,A | Promoted to active roster | | | Before |
| 4/27/2012 | EMP | Tekotte | Demoted to reserve roster | | | Before |
| 4/27/2012 | FOR | Chapman | Demoted to reserve roster | | | Before |
| 4/27/2012 | FOR | Chapman | Promoted to active roster | | | Before |
| 4/27/2012 | FOR | Cobb | Demoted to reserve roster | | | Before |
| 4/27/2012 | FOR | Francisco,J | Demoted to reserve roster | | | Before |
| 4/27/2012 | FOR | Gomez,J | Demoted to reserve roster | | | Before |
| 4/27/2012 | FOR | Gomez,J | Promoted to active roster | | | Before |
| 4/27/2012 | FOR | Gomez,J | Promoted to active roster | | | Before |
| 4/27/2012 | FOR | Hernandez,D | Demoted to reserve roster | | | Before |
| 4/27/2012 | FOR | Kendrick,K | Demoted to reserve roster | | | Before |
| 4/27/2012 | FOR | Lowe,M | Promoted to active roster | | | Before |
| 4/27/2012 | FOR | Marquis | Promoted to active roster | | | Before |
| 4/27/2012 | FOR | Richard | Demoted to reserve roster | | | Before |
| 4/27/2012 | FOR | Richard | Promoted to active roster | | | Before |
| 4/27/2012 | FOR | Willis | Promoted to active roster | | | Before |
| 4/27/2012 | INP | Betances | Promoted to active roster | | | Before |
| 4/27/2012 | INP | Strasburg | Demoted to reserve roster | | | Before |
| 4/27/2012 | LEG | Cahill | Promoted to active roster | | | Before |
| 4/27/2012 | LEG | Cahill | Promoted to active roster | | | Before |
| 4/27/2012 | LEG | Cishek | Promoted to active roster | | | Before |
| 4/27/2012 | LEG | Cishek | Promoted to active roster | | | Before |
| 4/27/2012 | LEG | Cueto | Demoted to reserve roster | | | Before |
| 4/27/2012 | LEG | Cueto | Demoted to reserve roster | | | Before |
| 4/27/2012 | LEG | Jansen | Demoted to reserve roster | | | Before |
| 4/27/2012 | LEG | Jansen | Demoted to reserve roster | | | Before |
| 4/27/2012 | LEG | Pineda | Demoted to reserve roster | | | Before |
| 4/27/2012 | LEG | Pineda | Demoted to reserve roster | | | Before |
| 4/27/2012 | LEG | Volstad | Promoted to active roster | | | Before |
| 4/27/2012 | LEG | Volstad | Promoted to active roster | | | Before |
| 4/27/2012 | MAI | Donald | Promoted to active roster | | | Before |
| 4/27/2012 | MAI | McGehee | Demoted to reserve roster | | | Before |
| 4/27/2012 | PHO | Colon | Promoted to active roster | | | Before |
| 4/27/2012 | PHO | Lewis,C | Demoted to reserve roster | | | Before |
| 4/27/2012 | PIN | Coleman,C | Promoted to active roster | | | Before |
| 4/27/2012 | PIN | Davis,R | Promoted to active roster | | | Before |
| 4/27/2012 | PIN | Reddick | Demoted to reserve roster | | | Before |
| 4/27/2012 | PIN | Wakefield | Demoted to reserve roster | | | Before |
| 4/27/2012 | SID | Harrison,M | Promoted to active roster | | | Before |
| 4/27/2012 | SID | Rodriguez,W | Demoted to reserve roster | | | Before |
| 4/27/2012 | SLG | Benoit | Demoted to reserve roster | | | Before |
| 4/27/2012 | SLG | Lynn | Promoted to active roster | | | Before |
| 4/27/2012 | SYN | Bowden | Promoted to active roster | | | Before |
| 4/27/2012 | SYN | Minor | Demoted to reserve roster | | | Before |
| 4/27/2012 | SYN | Worley | Promoted to active roster | | | Before |
| 4/27/2012 | SYN | Zambrano | Demoted to reserve roster | | | Before |
| 5/1/2012 | LEG | Adcock | Released | | | Before |
| 5/1/2012 | LEG | Adcock | Signed | | | Before |
| 5/1/2012 | LEG | Adcock | Signed | | | Before |
| 5/1/2012 | LEG | Worth | Released | | | Before |
| 5/1/2012 | LEG | Worth | Released | | | Before |
| 5/1/2012 | LEG | Worth | Signed | | | Before |
| 5/1/2012 | PEA | Duda | Demoted to reserve roster | | | Before |
| 5/1/2012 | PEA | LeMahieu | Promoted to active roster | | | Before |
| 5/1/2012 | SKT | Feldman | Promoted to active roster | | | Before |
| 5/1/2012 | SKT | Pestano | Demoted to reserve roster | | | Before |
| 5/3/2012 | B C | Prado | Promoted to active roster | | | Before |
| 5/3/2012 | B C | Reimold | Demoted to reserve roster | | | Before |
| 5/3/2012 | EAG | Beavan | Promoted to active roster | | | Before |
| 5/3/2012 | EAG | Moscoso | Demoted to reserve roster | | | Before |
| 5/3/2012 | EMP | Braden | Demoted to reserve roster | | | Before |
| 5/3/2012 | EMP | Ogando | Promoted to active roster | | | Before |
| 5/3/2012 | EMP | Tekotte | Demoted to reserve roster | | | Before |
| 5/3/2012 | EMP | Tekotte | Promoted to active roster | | | Before |
| 5/3/2012 | FOR | Francisco,J | Promoted to active roster | | | Before |
| 5/3/2012 | FOR | Gomez,J | Demoted to reserve roster | | | Before |
| 5/3/2012 | FOR | Gomez,J | Promoted to active roster | | | Before |
| 5/3/2012 | FOR | Hernandez,D | Promoted to active roster | | | Before |
| 5/3/2012 | FOR | Kendrick,K | Promoted to active roster | | | Before |
| 5/3/2012 | FOR | Lowe,M | Demoted to reserve roster | | | Before |
| 5/3/2012 | FOR | Marquis | Demoted to reserve roster | | | Before |
| 5/3/2012 | FOR | Paredes | Demoted to reserve roster | | | Before |
| 5/3/2012 | FOR | Richard | Demoted to reserve roster | | | Before |
| 5/3/2012 | FOR | Richard | Promoted to active roster | | | Before |
| 5/3/2012 | HSX | Brothers | Demoted to reserve roster | | | Before |
| 5/3/2012 | HSX | Buchholz,C | Demoted to reserve roster | | | Before |
| 5/3/2012 | HSX | Farnsworth | Demoted to reserve roster | | | Before |
| 5/3/2012 | HSX | Hughes,P | Promoted to active roster | | | Before |
| 5/3/2012 | HSX | Lopez,W | Promoted to active roster | | | Before |
| 5/3/2012 | HSX | Patton | Promoted to active roster | | | Before |
| 5/3/2012 | INP | Betances | Demoted to reserve roster | | | Before |
| 5/3/2012 | INP | Kotsay | Demoted to reserve roster | | | Before |
| 5/3/2012 | INP | McAllister | Demoted to reserve roster | | | Before |
| 5/3/2012 | INP | McAllister | Promoted to active roster | | | Before |
| 5/3/2012 | INP | Tabata | Promoted to active roster | | | Before |
| 5/3/2012 | INP | Viciedo | Promoted to active roster | | | Before |
| 5/3/2012 | IRI | Chen | Promoted to active roster | | | Before |
| 5/3/2012 | IRI | Garza | Demoted to reserve roster | | | Before |
| 5/3/2012 | IRI | Schumaker | Promoted to active roster | | | Before |
| 5/3/2012 | IRI | Utley | Demoted to reserve roster | | | Before |
| 5/3/2012 | LEG | Broxton | Demoted to reserve roster | | | Before |
| 5/3/2012 | LEG | Cishek | Demoted to reserve roster | | | Before |
| 5/3/2012 | LEG | Cueto | Promoted to active roster | | | Before |
| 5/3/2012 | LEG | Jansen | Promoted to active roster | | | Before |
| 5/3/2012 | LEG | Morales,F | Demoted to reserve roster | | | Before |
| 5/3/2012 | LEG | Pineda | Promoted to active roster | | | Before |
| 5/3/2012 | LEG | Sanchez,J | Demoted to reserve roster | | | Before |
| 5/3/2012 | LEG | Spence | Promoted to active roster | | | Before |
| 5/3/2012 | LEG | Volstad | Demoted to reserve roster | | | Before |
| 5/3/2012 | MAI | Collmenter | Demoted to reserve roster | | | Before |
| 5/3/2012 | MAI | Harrison,J | Demoted to reserve roster | | | Before |
| 5/3/2012 | MAI | Huff,D | Promoted to active roster | | | Before |
| 5/3/2012 | MAI | Patterson,C | Promoted to active roster | | | Before |
| 5/3/2012 | OUT | Allen | Promoted to active roster | | | Before |
| 5/3/2012 | OUT | Brown,Do | Demoted to reserve roster | | | Before |
| 5/3/2012 | OUT | Ceda | Demoted to reserve roster | | | Before |
| 5/3/2012 | OUT | Cooper | Demoted to reserve roster | | | Before |
| 5/3/2012 | OUT | Delgado | Demoted to reserve roster | | | Before |
| 5/3/2012 | OUT | Lawrie | Demoted to reserve roster | | | Before |
| 5/3/2012 | OUT | Rizzo | Promoted to active roster | | | Before |
| 5/3/2012 | OUT | Stewart,Z | Promoted to active roster | | | Before |
| 5/3/2012 | OUT | White | Promoted to active roster | | | Before |
| 5/3/2012 | OUT | Wood,Bl | Promoted to active roster | | | Before |
| 5/3/2012 | PHO | Colon | Demoted to reserve roster | | | Before |
| 5/3/2012 | PHO | Lewis,C | Promoted to active roster | | | Before |
| 5/3/2012 | PIN | Arroyo | Promoted to active roster | | | Before |
| 5/3/2012 | PIN | Moseley | Demoted to reserve roster | | | Before |
| 5/3/2012 | PIN | Murphy,Dan | Demoted to reserve roster | | | Before |
| 5/3/2012 | PIN | Paulino,F | Demoted to reserve roster | | | Before |
| 5/3/2012 | PIN | Sanchez,F | Promoted to active roster | | | Before |
| 5/3/2012 | PIN | Wakefield | Promoted to active roster | | | Before |
| 5/3/2012 | SCO | Bernadina | Demoted to reserve roster | | | Before |
| 5/3/2012 | SCO | Carrasco,C | Promoted to active roster | | | Before |
| 5/3/2012 | SCO | Castro,R | Promoted to active roster | | | Before |
| 5/3/2012 | SCO | Craig | Promoted to active roster | | | Before |
| 5/3/2012 | SCO | McCarthy | Demoted to reserve roster | | | Before |
| 5/3/2012 | SCO | Ross,D | Demoted to reserve roster | | | Before |
| 5/3/2012 | SLG | Boggs,M | Promoted to active roster | | | Before |
| 5/3/2012 | SLG | Brignac | Demoted to reserve roster | | | Before |
| 5/3/2012 | SLG | Devine | Promoted to active roster | | | Before |
| 5/3/2012 | SLG | Jurrjens | Promoted to active roster | | | Before |
| 5/3/2012 | SLG | Lynn | Demoted to reserve roster | | | Before |
| 5/3/2012 | SLG | Salas | Demoted to reserve roster | | | Before |
| 5/3/2012 | SLG | Scutaro | Promoted to active roster | | | Before |
| 5/3/2012 | SLG | Westbrook | Demoted to reserve roster | | | Before |
| 5/3/2012 | SYN | Bowden | Demoted to reserve roster | | | Before |
| 5/3/2012 | SYN | Lindblom | Promoted to active roster | | | Before |
| 5/7/2012 | REB | Carmona | Demoted to reserve roster | | | Before |
| 5/7/2012 | REB | Crow | Demoted to reserve roster | | | Before |
| 5/7/2012 | REB | Johnson,Jo | Promoted to active roster | | | Before |
| 5/7/2012 | REB | Soriano,R | Promoted to active roster | | | Before |
| 5/8/2012 | B C | Cecil | Demoted to reserve roster | | | Before |
| 5/8/2012 | B C | Flores | Promoted to active roster | | | Before |
| 5/8/2012 | B C | Hernandez,R | Demoted to reserve roster | | | Before |
| 5/8/2012 | B C | Oswalt | Promoted to active roster | | | Before |
| 5/8/2012 | B C | Reimold | Promoted to active roster | | | Before |
| 5/8/2012 | B C | Sizemore,S | Demoted to reserve roster | | | Before |
| 5/8/2012 | B C | Sweeney | Demoted to reserve roster | | | Before |
| 5/8/2012 | B C | Young,E | Promoted to active roster | | | Before |
| 5/8/2012 | DRI | Barton | Promoted to active roster | | | Before |
| 5/8/2012 | DRI | Giavotella | Promoted to active roster | | | Before |
| 5/8/2012 | DRI | Longoria | Demoted to reserve roster | | | Before |
| 5/8/2012 | DRI | Thome | Demoted to reserve roster | | | Before |
| 5/8/2012 | EAG | Janish | Demoted to reserve roster | | | Before |
| 5/8/2012 | EAG | Zimmerman | Promoted to active roster | | | Before |
| 5/8/2012 | OUT | Acosta | Signed | | | Before |
| 5/8/2012 | OUT | Allen | Promoted to active roster | | | Before |
| 5/8/2012 | OUT | Brown,Do | Demoted to reserve roster | | | Before |
| 5/8/2012 | OUT | Ceda | Released | | | Before |
| 5/8/2012 | OUT | Delgado | Demoted to reserve roster | | | Before |
| 5/8/2012 | OUT | Dotel | Demoted to reserve roster | | | Before |
| 5/8/2012 | OUT | Lawrie | Demoted to reserve roster | | | Before |
| 5/8/2012 | OUT | McGee | Demoted to reserve roster | | | Before |
| 5/8/2012 | OUT | Perry | Promoted to active roster | | | Before |
| 5/8/2012 | OUT | Rizzo | Promoted to active roster | | | Before |
| 5/8/2012 | OUT | White | Promoted to active roster | | | Before |
| 5/8/2012 | OUT | Wood,Bl | Promoted to active roster | | | Before |
| 5/8/2012 | PHO | Duncan | Promoted to active roster | | | Before |
| 5/8/2012 | PHO | Keppinger | Promoted to active roster | | | Before |
| 5/8/2012 | PHO | Kubel | Demoted to reserve roster | | | Before |
| 5/8/2012 | PHO | Ludwick | Demoted to reserve roster | | | Before |
| 5/8/2012 | PIN | Paulino,F | Demoted to reserve roster | | | Before |
| 5/8/2012 | PIN | Paulino,F | Promoted to active roster | | | Before |
| 5/8/2012 | PIN | Romero,R | Demoted to reserve roster | | | Before |
| 5/8/2012 | PIN | Weiland | Promoted to active roster | | | Before |
| 5/8/2012 | SLG | Benoit | Promoted to active roster | | | Before |
| 5/8/2012 | SLG | Brignac | Promoted to active roster | | | Before |
| 5/8/2012 | SLG | Devine | Demoted to reserve roster | | | Before |
| 5/8/2012 | SLG | Gorzelanny | Demoted to reserve roster | | | Before |
| 5/8/2012 | SLG | Jay | Demoted to reserve roster | | | Before |
| 5/8/2012 | SLG | Lynn | Promoted to active roster | | | Before |
| 5/8/2012 | SLG | Madson | Demoted to reserve roster | | | Before |
| 5/8/2012 | SLG | Presley | Promoted to active roster | | | Before |
| 5/8/2012 | SLG | Scutaro | Demoted to reserve roster | | | Before |
| 5/8/2012 | SLG | Vogelsong | Demoted to reserve roster | | | Before |
| 5/8/2012 | SLG | Westbrook | Promoted to active roster | | | Before |
| 5/9/2012 | FOR | Dirks | Promoted to active roster | | | Before |
| 5/9/2012 | FOR | Willis | Demoted to reserve roster | | | Before |
| 5/9/2012 | HSX | Blevins | Promoted to active roster | | | Before |
| 5/9/2012 | HSX | Litsch | Demoted to reserve roster | | | Before |
| 5/9/2012 | INP | Aviles | Promoted to active roster | | | Before |
| 5/9/2012 | INP | Dobbs | Demoted to reserve roster | | | Before |
| 5/9/2012 | INP | Quintero | Promoted to active roster | | | Before |
| 5/9/2012 | INP | Rosario,W | Demoted to reserve roster | | | Before |
| 5/9/2012 | IRI | Garza | Promoted to active roster | | | Before |
| 5/9/2012 | IRI | McDonald,Ja | Demoted to reserve roster | | | Before |
| 5/9/2012 | MAI | Collmenter | Promoted to active roster | | | Before |
| 5/9/2012 | MAI | Huff,D | Demoted to reserve roster | | | Before |
| 5/9/2012 | PEA | Carrera | Promoted to active roster | | | Before |
| 5/9/2012 | PEA | Patterson,E | Demoted to reserve roster | | | Before |
| 5/9/2012 | PIN | Coleman,C | Demoted to reserve roster | | | Before |
| 5/9/2012 | PIN | Davis,I | Promoted to active roster | | | Before |
| 5/9/2012 | PIN | Hafner | Demoted to reserve roster | | | Before |
| 5/9/2012 | PIN | Moseley | Promoted to active roster | | | Before |
| 5/9/2012 | PIN | Murphy,Dan | Promoted to active roster | | | Before |
| 5/9/2012 | PIN | Romero,R | Promoted to active roster | | | Before |
| 5/9/2012 | PIN | Sanchez,F | Demoted to reserve roster | | | Before |
| 5/9/2012 | PIN | Treanor | Promoted to active roster | | | Before |
| 5/9/2012 | PIN | Weiland | Demoted to reserve roster | | | Before |
| 5/9/2012 | PIN | Wilson,Bo | Demoted to reserve roster | | | Before |
| 5/9/2012 | QUI | Ackley | Demoted to reserve roster | | | Before |
| 5/9/2012 | QUI | Liddi | Promoted to active roster | | | Before |
| 5/9/2012 | QUI | Montero,J | Promoted to active roster | | | Before |
| 5/9/2012 | QUI | Pie | Promoted to active roster | | | Before |
| 5/9/2012 | QUI | Wells,C | Demoted to reserve roster | | | Before |
| 5/9/2012 | QUI | Wheeler | Demoted to reserve roster | | | Before |
| 5/9/2012 | SID | Hellickson | Demoted to reserve roster | | | Before |
| 5/9/2012 | SID | Rodriguez,W | Promoted to active roster | | | Before |
| 5/9/2012 | SKT | Gregerson | Promoted to active roster | | | Before |
| 5/9/2012 | SKT | Jones,G | Demoted to reserve roster | | | Before |
| 5/9/2012 | SKT | Matsuzaka | Promoted to active roster | | | Before |
| 5/9/2012 | SKT | Nicasio | Demoted to reserve roster | | | Before |
| 5/9/2012 | SKT | Span | Promoted to active roster | | | Before |
| 5/9/2012 | SKT | Wright,J | Demoted to reserve roster | | | Before |
| 5/9/2012 | SYN | Minor | Promoted to active roster | | | Before |
| 5/9/2012 | SYN | Thompson,R | Demoted to reserve roster | | | Before |
| 5/9/2012 | SYN | Worley | Demoted to reserve roster | | | Before |
| 5/9/2012 | SYN | Zambrano | Promoted to active roster | | | Before |
| 5/13/2012 | EMP | Lavarnway | Promoted to active roster | | | Before |
| 5/13/2012 | EMP | McKenry | Demoted to reserve roster | | | Before |
| 5/14/2012 | COM | League | Demoted to reserve roster | | | Before |
| 5/14/2012 | COM | Strop | Promoted to active roster | | | Before |
| 5/14/2012 | FOR | Chapman | Promoted to active roster | | | Before |
| 5/14/2012 | FOR | Dirks | Demoted to reserve roster | | | Before |
| 5/14/2012 | FOR | Francisco,J | Demoted to reserve roster | | | Before |
| 5/14/2012 | FOR | Gomez,J | Demoted to reserve roster | | | Before |
| 5/14/2012 | FOR | Lowe,M | Promoted to active roster | | | Before |
| 5/14/2012 | FOR | Marquis | Promoted to active roster | | | Before |
| 5/14/2012 | FOR | Ohlendorf | Released | | | Before |
| 5/14/2012 | FOR | Paredes | Promoted to active roster | | | Before |
| 5/14/2012 | FOR | Richard | Demoted to reserve roster | | | Before |
| 5/14/2012 | FOR | Richard | Promoted to active roster | | | Before |
| 5/14/2012 | FOR | Sale | Demoted to reserve roster | | | Before |
| 5/14/2012 | FOR | Sutton | Signed | | | Before |
| 5/14/2012 | FOR | Wilson,Br | Demoted to reserve roster | | | Before |
| 5/14/2012 | LEG | Boesch | Demoted to reserve roster | | | Before |
| 5/14/2012 | LEG | Carter | Promoted to active roster | | | Before |
| 5/14/2012 | LEG | Cishek | Promoted to active roster | | | Before |
| 5/14/2012 | LEG | Harang | Demoted to reserve roster | | | Before |
| 5/14/2012 | LEG | Hudson,O | Demoted to reserve roster | | | Before |
| 5/14/2012 | LEG | Jackson,C | Promoted to active roster | | | Before |
| 5/14/2012 | LEG | Sanchez,J | Promoted to active roster | | | Before |
| 5/14/2012 | LEG | Sipp | Demoted to reserve roster | | | Before |
| 5/14/2012 | SLG | Benoit | Promoted to active roster | | | Before |
| 5/14/2012 | SLG | Boggs,M | Demoted to reserve roster | | | Before |
| 5/14/2012 | SLG | Devine | Demoted to reserve roster | | | Before |
| 5/14/2012 | SLG | Salas | Promoted to active roster | | | Before |
| 5/15/2012 | B C | Belt | Promoted to active roster | | | Before |
| 5/15/2012 | B C | Flores | Demoted to reserve roster | | | Before |
| 5/15/2012 | B C | Hernandez,R | Promoted to active roster | | | Before |
| 5/15/2012 | B C | Reimold | Demoted to reserve roster | | | Before |
| 5/15/2012 | EAG | Beavan | Demoted to reserve roster | | | Before |
| 5/15/2012 | EAG | Moscoso | Promoted to active roster | | | Before |
| 5/15/2012 | HSX | Blevins | Demoted to reserve roster | | | Before |
| 5/15/2012 | HSX | Brothers | Promoted to active roster | | | Before |
| 5/15/2012 | OUT | Brown,Do | Promoted to active roster | | | Before |
| 5/15/2012 | OUT | Cooper | Demoted to reserve roster | | | Before |
| 5/15/2012 | OUT | Delgado | Promoted to active roster | | | Before |
| 5/15/2012 | OUT | Lawrie | Promoted to active roster | | | Before |
| 5/15/2012 | OUT | Rizzo | Demoted to reserve roster | | | Before |
| 5/15/2012 | OUT | Rizzo | Promoted to active roster | | | Before |
| 5/15/2012 | OUT | Valbuena | Demoted to reserve roster | | | Before |
| 5/15/2012 | OUT | White | Demoted to reserve roster | | | Before |
| 5/15/2012 | QUI | Ackley | Promoted to active roster | | | Before |
| 5/15/2012 | QUI | Baker,S | Promoted to active roster | | | Before |
| 5/15/2012 | QUI | Garcia,F | Demoted to reserve roster | | | Before |
| 5/15/2012 | QUI | Liddi | Demoted to reserve roster | | | Before |
| 5/15/2012 | QUI | Pie | Demoted to reserve roster | | | Before |
| 5/15/2012 | QUI | Wells,C | Promoted to active roster | | | Before |
| 5/15/2012 | QUI | Wheeler | Promoted to active roster | | | Before |
| 5/15/2012 | QUI | Whiteside | Demoted to reserve roster | | | Before |
| 5/15/2012 | REB | Crow | Promoted to active roster | | | Before |
| 5/15/2012 | REB | Soriano,R | Demoted to reserve roster | | | Before |
| 5/15/2012 | SCO | Bernadina | Promoted to active roster | | | Before |
| 5/15/2012 | SCO | Castro,R | Demoted to reserve roster | | | Before |
| 5/15/2012 | SCO | Craig | Demoted to reserve roster | | | Before |
| 5/15/2012 | SCO | Drabek | Demoted to reserve roster | | | Before |
| 5/15/2012 | SCO | Ross,T | Promoted to active roster | | | Before |
| 5/15/2012 | SCO | Snyder,C | Promoted to active roster | | | Before |
| 5/15/2012 | SID | Davis,C | Promoted to active roster | | | Before |
| 5/15/2012 | SID | Rodriguez,I | Demoted to reserve roster | | | Before |
| 5/19/2012 | RLF | Jenks | Promoted to active roster | | | Before |
| 5/19/2012 | RLF | Vasquez,E | Demoted to reserve roster | | | Before |
| 5/20/2012 | EAG | Beavan | Promoted to active roster | | | Before |
| 5/20/2012 | EAG | Janish | Promoted to active roster | | | Before |
| 5/20/2012 | EAG | Moscoso | Demoted to reserve roster | | | Before |
| 5/20/2012 | EAG | Zimmerman | Demoted to reserve roster | | | Before |
| 5/20/2012 | REB | Carmona | Promoted to active roster | | | Before |
| 5/20/2012 | REB | Wilhelmsen | Demoted to reserve roster | | | Before |
| 5/21/2012 | BOU | Betemit | Demoted to reserve roster | | | Before |
| 5/21/2012 | BOU | Jones,C | Promoted to active roster | | | Before |
| 5/21/2012 | COM | League | Promoted to active roster | | | Before |
| 5/21/2012 | COM | Strop | Demoted to reserve roster | | | Before |
| 5/21/2012 | EMP | Lavarnway | Demoted to reserve roster | | | Before |
| 5/21/2012 | EMP | McKenry | Promoted to active roster | | | Before |
| 5/21/2012 | FOR | Hernandez,D | Demoted to reserve roster | | | Before |
| 5/21/2012 | FOR | Wilson,Br | Promoted to active roster | | | Before |
| 5/21/2012 | HSX | Capuano | Demoted to reserve roster | | | Before |
| 5/21/2012 | HSX | Farnsworth | Promoted to active roster | | | Before |
| 5/21/2012 | HSX | Gee | Promoted to active roster | | | Before |
| 5/21/2012 | HSX | Putz | Demoted to reserve roster | | | Before |
| 5/21/2012 | INP | Gordon,D | Demoted to reserve roster | | | Before |
| 5/21/2012 | INP | Nunez,E | Promoted to active roster | | | Before |
| 5/21/2012 | IRI | Garza | Demoted to reserve roster | | | Before |
| 5/21/2012 | IRI | Garza | Promoted to active roster | | | Before |
| 5/21/2012 | IRI | McDonald,Ja | Promoted to active roster | | | Before |
| 5/21/2012 | IRI | Schumaker | Demoted to reserve roster | | | Before |
| 5/21/2012 | IRI | Utley | Promoted to active roster | | | Before |
| 5/21/2012 | IRI | Wang | Demoted to reserve roster | | | Before |
| 5/21/2012 | MAI | Gentry | Demoted to reserve roster | | | Before |
| 5/21/2012 | MAI | Harrison,J | Promoted to active roster | | | Before |
| 5/21/2012 | PEA | Arrieta | Demoted to reserve roster | | | Before |
| 5/21/2012 | PEA | Chatwood | Promoted to active roster | | | Before |
| 5/21/2012 | PEA | LeMahieu | Demoted to reserve roster | | | Before |
| 5/21/2012 | PEA | Patterson,E | Promoted to active roster | | | Before |
| 5/21/2012 | PHO | Abreu,B | Demoted to reserve roster | | | Before |
| 5/21/2012 | PHO | Colon | Promoted to active roster | | | Before |
| 5/21/2012 | PHO | Kubel | Promoted to active roster | | | Before |
| 5/21/2012 | PHO | Lewis,C | Demoted to reserve roster | | | Before |
| 5/21/2012 | PIN | Moseley | Demoted to reserve roster | | | Before |
| 5/21/2012 | PIN | Paulino,F | Promoted to active roster | | | Before |
| 5/21/2012 | PIN | Reddick | Promoted to active roster | | | Before |
| 5/21/2012 | PIN | Schierholtz | Demoted to reserve roster | | | Before |
| 5/21/2012 | QUI | Baker,S | Demoted to reserve roster | | | Before |
| 5/21/2012 | QUI | Blanton | Demoted to reserve roster | | | Before |
| 5/21/2012 | QUI | Duffy | Promoted to active roster | | | Before |
| 5/21/2012 | QUI | Garcia,F | Promoted to active roster | | | Before |
| 5/21/2012 | QUI | Harden | Demoted to reserve roster | | | Before |
| 5/21/2012 | QUI | Harden | Promoted to active roster | | | Before |
| 5/21/2012 | QUI | Liddi | Promoted to active roster | | | Before |
| 5/21/2012 | QUI | Lyles | Demoted to reserve roster | | | Before |
| 5/21/2012 | QUI | Montero,J | Demoted to reserve roster | | | Before |
| 5/21/2012 | QUI | Whiteside | Promoted to active roster | | | Before |
| 5/21/2012 | SCO | Bernadina | Demoted to reserve roster | | | Before |
| 5/21/2012 | SCO | Castro,R | Promoted to active roster | | | Before |
| 5/21/2012 | SCO | Craig | Promoted to active roster | | | Before |
| 5/21/2012 | SCO | Mathis | Demoted to reserve roster | | | Before |
| 5/21/2012 | SKT | Blackburn | Promoted to active roster | | | Before |
| 5/21/2012 | SKT | Damon | Promoted to active roster | | | Before |
| 5/21/2012 | SKT | Hamilton,J | Demoted to reserve roster | | | Before |
| 5/21/2012 | SKT | Hernandez,L | Demoted to reserve roster | | | Before |
| 5/21/2012 | SKT | Pestano | Demoted to reserve roster | | | Before |
| 5/21/2012 | SKT | Wright,J | Promoted to active roster | | | Before |
| 5/21/2012 | SLG | Devine | Demoted to reserve roster | | | Before |
| 5/21/2012 | SLG | Presley | Promoted to active roster | | | Before |
| 5/21/2012 | SLG | Salas | Promoted to active roster | | | Before |
| 5/21/2012 | SLG | Venable | Demoted to reserve roster | | | Before |
| 5/21/2012 | SLG | Vogelsong | Demoted to reserve roster | | | Before |
| 5/21/2012 | SLG | Westbrook | Promoted to active roster | | | Before |
| 5/21/2012 | SYN | Lindblom | Demoted to reserve roster | | | Before |
| 5/21/2012 | SYN | Thompson,R | Promoted to active roster | | | Before |
| 5/21/2012 | SYN | Worley | Promoted to active roster | | | Before |
| 5/21/2012 | SYN | Zambrano | Demoted to reserve roster | | | Before |
| 5/25/2012 | OUT | Blanks | Demoted to reserve roster | | | Before |
| 5/25/2012 | OUT | Brown,Do | Demoted to reserve roster | | | Before |
| 5/25/2012 | OUT | Cooper | Promoted to active roster | | | Before |
| 5/25/2012 | OUT | Delgado | Demoted to reserve roster | | | Before |
| 5/25/2012 | OUT | Stewart,Z | Promoted to active roster | | | Before |
| 5/25/2012 | OUT | White | Promoted to active roster | | | Before |
| 5/25/2012 | SLG | Benoit | Promoted to active roster | | | Before |
| 5/25/2012 | SLG | Boggs,M | Demoted to reserve roster | | | Before |
| 5/25/2012 | SLG | Jurrjens | Demoted to reserve roster | | | Before |
| 5/25/2012 | SLG | Mujica | Demoted to reserve roster | | | Before |
| 5/25/2012 | SLG | Mujica | Promoted to active roster | | | Before |
| 5/25/2012 | SLG | Vogelsong | Promoted to active roster | | | Before |
| 5/26/2012 | B C | Aybar | Demoted to reserve roster | | | Before |
| 5/26/2012 | B C | Belt | Demoted to reserve roster | | | Before |
| 5/26/2012 | B C | Flores | Promoted to active roster | | | Before |
| 5/26/2012 | B C | Gomez,C | Promoted to active roster | | | Before |
| 5/26/2012 | B C | LaPorta | Demoted to reserve roster | | | Before |
| 5/26/2012 | B C | Lueke | Promoted to active roster | | | Before |
| 5/26/2012 | B C | Masset | Demoted to reserve roster | | | Before |
| 5/26/2012 | B C | Matusz | Promoted to active roster | | | Before |
| 5/26/2012 | B C | Narveson | Demoted to reserve roster | | | Before |
| 5/26/2012 | B C | Narveson | Promoted to active roster | | | Before |
| 5/26/2012 | B C | Reimold | Promoted to active roster | | | Before |
| 5/26/2012 | B C | Sizemore,S | Promoted to active roster | | | Before |
| 5/26/2012 | B C | Upton,J | Demoted to reserve roster | | | Before |
| 5/26/2012 | B C | Ziegler | Demoted to reserve roster | | | Before |
| 5/26/2012 | DRI | Barton | Demoted to reserve roster | | | Before |
| 5/26/2012 | DRI | Callaspo | Demoted to reserve roster | | | Before |
| 5/26/2012 | DRI | Hinske | Promoted to active roster | | | Before |
| 5/26/2012 | DRI | Longoria | Promoted to active roster | | | Before |
| 5/26/2012 | DRI | McDonald,D | Demoted to reserve roster | | | Before |
| 5/26/2012 | DRI | Navarro,Y | Demoted to reserve roster | | | Before |
| 5/26/2012 | DRI | Navarro,Y | Promoted to active roster | | | Before |
| 5/26/2012 | DRI | Thome | Promoted to active roster | | | Before |
| 5/26/2012 | EAG | Kennedy,A | Demoted to reserve roster | | | Before |
| 5/26/2012 | EAG | Zimmerman | Promoted to active roster | | | Before |
| 5/26/2012 | EMP | Darnell | Promoted to active roster | | | Before |
| 5/26/2012 | EMP | LaRoche,Ad | Demoted to reserve roster | | | Before |
| 5/26/2012 | EMP | Rolen | Demoted to reserve roster | | | Before |
| 5/26/2012 | EMP | Rolen | Promoted to active roster | | | Before |
| 5/26/2012 | FOR | Chapman | Demoted to reserve roster | | | Before |
| 5/26/2012 | FOR | Sale | Promoted to active roster | | | Before |
| 5/26/2012 | FOR | Seager | Promoted to active roster | | | Before |
| 5/26/2012 | FOR | Sutton | Demoted to reserve roster | | | Before |
| 5/26/2012 | HSX | Colvin | Promoted to active roster | | | Before |
| 5/26/2012 | HSX | de Aza | Demoted to reserve roster | | | Before |
| 5/26/2012 | HSX | Farnsworth | Demoted to reserve roster | | | Before |
| 5/26/2012 | HSX | Flowers | Promoted to active roster | | | Before |
| 5/26/2012 | HSX | Pierzynski | Demoted to reserve roster | | | Before |
| 5/26/2012 | HSX | Putz | Promoted to active roster | | | Before |
| 5/26/2012 | LEG | Boesch | Promoted to active roster | | | Before |
| 5/26/2012 | LEG | Carter | Demoted to reserve roster | | | Before |
| 5/26/2012 | LEG | Cishek | Demoted to reserve roster | | | Before |
| 5/26/2012 | LEG | Downs,M | Demoted to reserve roster | | | Before |
| 5/26/2012 | LEG | Frieri | Demoted to reserve roster | | | Before |
| 5/26/2012 | LEG | Gutierrez,J | Promoted to active roster | | | Before |
| 5/26/2012 | LEG | Harang | Promoted to active roster | | | Before |
| 5/26/2012 | LEG | Hudson,O | Promoted to active roster | | | Before |
| 5/26/2012 | LEG | Morales,F | Promoted to active roster | | | Before |
| 5/26/2012 | LEG | Pelfrey | Demoted to reserve roster | | | Before |
| 5/26/2012 | LEG | Sanchez,J | Demoted to reserve roster | | | Before |
| 5/26/2012 | LEG | Sipp | Promoted to active roster | | | Before |
| 5/26/2012 | LEG | Spence | Demoted to reserve roster | | | Before |
| 5/26/2012 | LEG | Volstad | Promoted to active roster | | | Before |
| 5/26/2012 | PEA | LeMahieu | Promoted to active roster | | | Before |
| 5/26/2012 | PEA | Patterson,E | Demoted to reserve roster | | | Before |
| 5/26/2012 | PHO | Duncan | Demoted to reserve roster | | | Before |
| 5/26/2012 | PHO | Hawkins | Demoted to reserve roster | | | Before |
| 5/26/2012 | PHO | Humber | Demoted to reserve roster | | | Before |
| 5/26/2012 | PHO | Lewis,C | Promoted to active roster | | | Before |
| 5/26/2012 | PHO | Posada | Promoted to active roster | | | Before |
| 5/26/2012 | PHO | Webb | Promoted to active roster | | | Before |
| 5/26/2012 | PIN | Coleman,C | Promoted to active roster | | | Before |
| 5/26/2012 | PIN | Furcal | Demoted to reserve roster | | | Before |
| 5/26/2012 | PIN | Hafner | Promoted to active roster | | | Before |
| 5/26/2012 | PIN | Paulino,F | Demoted to reserve roster | | | Before |
| 5/26/2012 | PIN | Treanor | Demoted to reserve roster | | | Before |
| 5/26/2012 | PIN | Wilson,Bo | Promoted to active roster | | | Before |
| 5/26/2012 | QUI | Ackley | Demoted to reserve roster | | | Before |
| 5/26/2012 | QUI | Blanton | Promoted to active roster | | | Before |
| 5/26/2012 | QUI | Harden | Promoted to active roster | | | Before |
| 5/26/2012 | QUI | Hernandez,F | Demoted to reserve roster | | | Before |
| 5/26/2012 | QUI | Hernandez,F | Promoted to active roster | | | Before |
| 5/26/2012 | QUI | Janssen | Demoted to reserve roster | | | Before |
| 5/26/2012 | QUI | Lyles | Promoted to active roster | | | Before |
| 5/26/2012 | QUI | Martinez,J | Demoted to reserve roster | | | Before |
| 5/26/2012 | QUI | Morrow | Demoted to reserve roster | | | Before |
| 5/26/2012 | QUI | Pie | Promoted to active roster | | | Before |
| 5/26/2012 | REB | Bedard | Demoted to reserve roster | | | Before |
| 5/26/2012 | REB | Crow | Demoted to reserve roster | | | Before |
| 5/26/2012 | REB | Johnson,Jo | Demoted to reserve roster | | | Before |
| 5/26/2012 | REB | Peavy | Promoted to active roster | | | Before |
| 5/26/2012 | REB | Perez,R | Demoted to reserve roster | | | Before |
| 5/26/2012 | REB | Soriano,R | Promoted to active roster | | | Before |
| 5/26/2012 | REB | Torres,Al | Promoted to active roster | | | Before |
| 5/26/2012 | REB | Wilhelmsen | Promoted to active roster | | | Before |
| 5/26/2012 | SCO | Drabek | Promoted to active roster | | | Before |
| 5/26/2012 | SCO | Ross,T | Demoted to reserve roster | | | Before |
| 5/26/2012 | SID | Anderson,B | Demoted to reserve roster | | | Before |
| 5/26/2012 | SID | Hellickson | Promoted to active roster | | | Before |
| 5/26/2012 | SYN | Bowden | Promoted to active roster | | | Before |
| 5/26/2012 | SYN | Minor | Demoted to reserve roster | | | Before |
| 5/26/2012 | SYN | Worley | Demoted to reserve roster | | | Before |
| 5/26/2012 | SYN | Zambrano | Promoted to active roster | | | Before |
| 5/27/2012 | SKT | Gregerson | Demoted to reserve roster | | | Before |
| 5/27/2012 | SKT | Matsuzaka | Demoted to reserve roster | | | Before |
| 5/27/2012 | SKT | Moreland | Promoted to active roster | | | Before |
| 5/27/2012 | SKT | Nicasio | Promoted to active roster | | | Before |
| 5/27/2012 | SKT | Overbay | Demoted to reserve roster | | | Before |
| 5/27/2012 | SKT | Pestano | Promoted to active roster | | | Before |
| 6/1/2012 | B C | Aybar | Promoted to active roster | | | Before |
| 6/1/2012 | B C | Borbon | Promoted to active roster | | | Before |
| 6/1/2012 | B C | Prado | Demoted to reserve roster | | | Before |
| 6/1/2012 | B C | Sogard | Demoted to reserve roster | | | Before |
| 6/1/2012 | EMP | Hendriks | Promoted to active roster | | | Before |
| 6/1/2012 | EMP | Hunter,Tom | Demoted to reserve roster | | | Before |
| 6/1/2012 | FOR | Dirks | Promoted to active roster | | | Before |
| 6/1/2012 | FOR | Goldschmidt | Demoted to reserve roster | | | Before |
| 6/1/2012 | FOR | Hernandez,D | Promoted to active roster | | | Before |
| 6/1/2012 | FOR | Lowe,M | Demoted to reserve roster | | | Before |
| 6/1/2012 | FOR | Seager | Demoted to reserve roster | | | Before |
| 6/1/2012 | FOR | Sutton | Promoted to active roster | | | Before |
| 6/1/2012 | IRI | Coghlan | Promoted to active roster | | | Before |
| 6/1/2012 | IRI | Ortiz,D | Demoted to reserve roster | | | Before |
| 6/1/2012 | OUT | Cedeno,R | Promoted to active roster | | | Before |
| 6/1/2012 | OUT | Lawrie | Demoted to reserve roster | | | Before |
| 6/1/2012 | QUI | Liddi | Demoted to reserve roster | | | Before |
| 6/1/2012 | QUI | Phelps | Promoted to active roster | | | Before |
| 6/1/2012 | REB | Alvarez,P | Promoted to active roster | | | Before |
| 6/1/2012 | REB | Bedard | Promoted to active roster | | | Before |
| 6/1/2012 | REB | Crow | Promoted to active roster | | | Before |
| 6/1/2012 | REB | Ellis,A | Demoted to reserve roster | | | Before |
| 6/1/2012 | REB | Peavy | Demoted to reserve roster | | | Before |
| 6/1/2012 | REB | Perez,R | Promoted to active roster | | | Before |
| 6/1/2012 | REB | Soriano,R | Demoted to reserve roster | | | Before |
| 6/1/2012 | REB | Wilhelmsen | Demoted to reserve roster | | | Before |
| 6/3/2012 | EAG | Beavan | Demoted to reserve roster | | | Before |
| 6/3/2012 | EAG | Moscoso | Promoted to active roster | | | Before |
| 6/3/2012 | EMP | DeWitt | Released | | | Before |
| 6/3/2012 | EMP | Kuo | Released | | | Before |
| 6/3/2012 | EMP | Ordonez | Signed | | | Before |
| 6/3/2012 | EMP | Towles | Signed | | | Before |
| 6/3/2012 | HSX | Arencibia | Demoted to reserve roster | | | Before |
| 6/3/2012 | HSX | Capuano | Promoted to active roster | | | Before |
| 6/3/2012 | HSX | de Aza | Promoted to active roster | | | Before |
| 6/3/2012 | HSX | Gee | Demoted to reserve roster | | | Before |
| 6/3/2012 | HSX | Morgan | Demoted to reserve roster | | | Before |
| 6/3/2012 | HSX | Pierzynski | Promoted to active roster | | | Before |
| 6/3/2012 | LEG | Carp | Demoted to reserve roster | | | Before |
| 6/3/2012 | LEG | Carter | Promoted to active roster | | | Before |
| 6/3/2012 | LEG | Frieri | Promoted to active roster | | | Before |
| 6/3/2012 | LEG | Gutierrez,J | Demoted to reserve roster | | | Before |
| 6/3/2012 | LEG | Hand | Promoted to active roster | | | Before |
| 6/3/2012 | LEG | Jansen | Demoted to reserve roster | | | Before |
| 6/3/2012 | LEG | Sanchez,J | Promoted to active roster | | | Before |
| 6/3/2012 | LEG | Spence | Promoted to active roster | | | Before |
| 6/3/2012 | LEG | Takahashi | Demoted to reserve roster | | | Before |
| 6/3/2012 | LEG | Volstad | Demoted to reserve roster | | | Before |
| 6/3/2012 | MAI | Harrison,J | Demoted to reserve roster | | | Before |
| 6/3/2012 | MAI | McGehee | Promoted to active roster | | | Before |
| 6/3/2012 | MAI | Molina,J | Demoted to reserve roster | | | Before |
| 6/3/2012 | MAI | Stewart,C | Promoted to active roster | | | Before |
| 6/3/2012 | PHO | Colon | Demoted to reserve roster | | | Before |
| 6/3/2012 | PHO | Humber | Promoted to active roster | | | Before |
| 6/3/2012 | PHO | Johnson,C | Demoted to reserve roster | | | Before |
| 6/3/2012 | PHO | Johnson,C | Promoted to active roster | | | Before |
| 6/3/2012 | PIN | Ankiel | Demoted to reserve roster | | | Before |
| 6/3/2012 | PIN | Coleman,C | Demoted to reserve roster | | | Before |
| 6/3/2012 | PIN | Furcal | Promoted to active roster | | | Before |
| 6/3/2012 | PIN | Paulino,F | Promoted to active roster | | | Before |
| 6/3/2012 | SCO | Latos | Demoted to reserve roster | | | Before |
| 6/3/2012 | SCO | McCarthy | Promoted to active roster | | | Before |
| 6/3/2012 | SKT | Badenhop | Demoted to reserve roster | | | Before |
| 6/3/2012 | SKT | Badenhop | Promoted to active roster | | | Before |
| 6/3/2012 | SKT | Feldman | Promoted to active roster | | | Before |
| 6/3/2012 | SKT | Francisco,B | Demoted to reserve roster | | | Before |
| 6/3/2012 | SKT | Hamilton,J | Promoted to active roster | | | Before |
| 6/3/2012 | SKT | Hernandez,L | Promoted to active roster | | | Before |
| 6/3/2012 | SKT | Jones,G | Promoted to active roster | | | Before |
| 6/3/2012 | SKT | Kuroda | Demoted to reserve roster | | | Before |
| 6/3/2012 | SKT | Pestano | Demoted to reserve roster | | | Before |
| 6/3/2012 | SKT | Span | Demoted to reserve roster | | | Before |
| 6/3/2012 | SYN | Worley | Promoted to active roster | | | Before |
| 6/3/2012 | SYN | Zambrano | Demoted to reserve roster | | | Before |
| 6/7/2012 | HSX | Arencibia | Promoted to active roster | | | Before |
| 6/7/2012 | HSX | Capuano | Demoted to reserve roster | | | Before |
| 6/7/2012 | HSX | de Aza | Demoted to reserve roster | | | Before |
| 6/7/2012 | HSX | Farnsworth | Promoted to active roster | | | Before |
| 6/7/2012 | HSX | Flowers | Demoted to reserve roster | | | Before |
| 6/7/2012 | HSX | Gee | Promoted to active roster | | | Before |
| 6/7/2012 | HSX | Lopez,W | Demoted to reserve roster | | | Before |
| 6/7/2012 | HSX | Morgan | Promoted to active roster | | | Before |
| 6/8/2012 | EMP | Braden | Promoted to active roster | | | Before |
| 6/8/2012 | EMP | Darnell | Demoted to reserve roster | | | Before |
| 6/8/2012 | EMP | Ogando | Demoted to reserve roster | | | Before |
| 6/8/2012 | EMP | Rolen | Promoted to active roster | | | Before |
| 6/9/2012 | BOU | Hagadone | Demoted to reserve roster | | | Before |
| 6/9/2012 | BOU | Williams,J | Promoted to active roster | | | Before |
| 6/9/2012 | DRI | Hinske | Demoted to reserve roster | | | Before |
| 6/9/2012 | DRI | McDonald,D | Promoted to active roster | | | Before |
| 6/9/2012 | FOR | Chapman | Promoted to active roster | | | Before |
| 6/9/2012 | FOR | Lowe,M | Promoted to active roster | | | Before |
| 6/9/2012 | FOR | Nova | Demoted to reserve roster | | | Before |
| 6/9/2012 | FOR | Richard | Promoted to active roster | | | Before |
| 6/9/2012 | FOR | Rzepczynski | Demoted to reserve roster | | | Before |
| 6/9/2012 | FOR | Wilson,Br | Demoted to reserve roster | | | Before |
| 6/9/2012 | MAI | Donald | Demoted to reserve roster | | | Before |
| 6/9/2012 | MAI | Gentry | Promoted to active roster | | | Before |
| 6/9/2012 | MAI | Harrison,J | Promoted to active roster | | | Before |
| 6/9/2012 | MAI | Patterson,C | Demoted to reserve roster | | | Before |
| 6/9/2012 | PEA | Lidge | Demoted to reserve roster | | | Before |
| 6/9/2012 | PEA | Wade | Promoted to active roster | | | Before |
| 6/9/2012 | PHO | Baker,Je | Demoted to reserve roster | | | Before |
| 6/9/2012 | PHO | Colon | Promoted to active roster | | | Before |
| 6/9/2012 | PHO | Duncan | Promoted to active roster | | | Before |
| 6/9/2012 | PHO | Johnson,C | Promoted to active roster | | | Before |
| 6/9/2012 | PHO | Lewis,C | Demoted to reserve roster | | | Before |
| 6/9/2012 | PHO | Posada | Demoted to reserve roster | | | Before |
| 6/9/2012 | PIN | Ankiel | Promoted to active roster | | | Before |
| 6/9/2012 | PIN | Arroyo | Demoted to reserve roster | | | Before |
| 6/9/2012 | PIN | Davis,I | Demoted to reserve roster | | | Before |
| 6/9/2012 | PIN | Davis,R | Demoted to reserve roster | | | Before |
| 6/9/2012 | PIN | Davis,R | Promoted to active roster | | | Before |
| 6/9/2012 | PIN | Hafner | Demoted to reserve roster | | | Before |
| 6/9/2012 | PIN | Moseley | Promoted to active roster | | | Before |
| 6/9/2012 | PIN | Murphy,Dan | Demoted to reserve roster | | | Before |
| 6/9/2012 | PIN | Murphy,Dan | Promoted to active roster | | | Before |
| 6/9/2012 | PIN | Reddick | Demoted to reserve roster | | | Before |
| 6/9/2012 | PIN | Sanchez,F | Promoted to active roster | | | Before |
| 6/9/2012 | PIN | Schierholtz | Promoted to active roster | | | Before |
| 6/9/2012 | PIN | Treanor | Promoted to active roster | | | Before |
| 6/9/2012 | PIN | Wilson,Bo | Demoted to reserve roster | | | Before |
| 6/9/2012 | QUI | Baker,S | Promoted to active roster | | | Before |
| 6/9/2012 | QUI | Britton | Demoted to reserve roster | | | Before |
| 6/9/2012 | QUI | Garcia,F | Demoted to reserve roster | | | Before |
| 6/9/2012 | QUI | Morrow | Promoted to active roster | | | Before |
| 6/9/2012 | REB | Bedard | Demoted to reserve roster | | | Before |
| 6/9/2012 | REB | Johnson,Ji | Demoted to reserve roster | | | Before |
| 6/9/2012 | REB | Peavy | Promoted to active roster | | | Before |
| 6/9/2012 | REB | Soriano,R | Promoted to active roster | | | Before |
| 6/9/2012 | RLF | Alonso | Promoted to active roster | | | Before |
| 6/9/2012 | RLF | Bell,T | Promoted to active roster | | | Before |
| 6/9/2012 | RLF | Choo | Demoted to reserve roster | | | Before |
| 6/9/2012 | RLF | Gutierrez,F | Demoted to reserve roster | | | Before |
| 6/9/2012 | RLF | Karstens | Demoted to reserve roster | | | Before |
| 6/9/2012 | RLF | Robinson,T | Promoted to active roster | | | Before |
| 6/9/2012 | SCO | Bernadina | Promoted to active roster | | | Before |
| 6/9/2012 | SCO | Carrasco,C | Demoted to reserve roster | | | Before |
| 6/9/2012 | SCO | Castro,R | Demoted to reserve roster | | | Before |
| 6/9/2012 | SCO | Craig | Demoted to reserve roster | | | Before |
| 6/9/2012 | SCO | Mathis | Promoted to active roster | | | Before |
| 6/9/2012 | SCO | Ross,T | Promoted to active roster | | | Before |
| 6/9/2012 | SID | Ayala | Promoted to active roster | | | Before |
| 6/9/2012 | SID | Davis,C | Demoted to reserve roster | | | Before |
| 6/9/2012 | SID | Davis,W | Demoted to reserve roster | | | Before |
| 6/9/2012 | SID | Davis,W | Promoted to active roster | | | Before |
| 6/9/2012 | SID | Detwiler | Demoted to reserve roster | | | Before |
| 6/9/2012 | SID | Detwiler | Promoted to active roster | | | Before |
| 6/9/2012 | SID | Parnell | Demoted to reserve roster | | | Before |
| 6/9/2012 | SID | Rodriguez,I | Promoted to active roster | | | Before |
| 6/9/2012 | SKT | Feldman | Demoted to reserve roster | | | Before |
| 6/9/2012 | SKT | Gregerson | Promoted to active roster | | | Before |
| 6/9/2012 | SKT | Kuroda | Promoted to active roster | | | Before |
| 6/9/2012 | SKT | Overbay | Promoted to active roster | | | Before |
| 6/9/2012 | SKT | Uggla | Demoted to reserve roster | | | Before |
| 6/9/2012 | SKT | Vargas | Demoted to reserve roster | | | Before |
| 6/9/2012 | SLG | Jurrjens | Promoted to active roster | | | Before |
| 6/9/2012 | SLG | Westbrook | Demoted to reserve roster | | | Before |
| 6/9/2012 | SYN | Bailey,H | Demoted to reserve roster | | | Before |
| 6/9/2012 | SYN | Beachy | Demoted to reserve roster | | | Before |
| 6/9/2012 | SYN | Bowden | Demoted to reserve roster | | | Before |
| 6/9/2012 | SYN | Carreno | Promoted to active roster | | | Before |
| 6/9/2012 | SYN | Eovaldi | Promoted to active roster | | | Before |
| 6/9/2012 | SYN | Lindblom | Promoted to active roster | | | Before |
| 6/9/2012 | SYN | Minor | Promoted to active roster | | | Before |
| 6/9/2012 | SYN | Rivera,Ma | Demoted to reserve roster | | | Before |
| 6/9/2012 | SYN | Uehara | Demoted to reserve roster | | | Before |
| 6/9/2012 | SYN | Zambrano | Promoted to active roster | | | Before |
| 6/13/2012 | OUT | Allen | Demoted to reserve roster | | | Before |
| 6/13/2012 | OUT | Blanks | Promoted to active roster | | | Before |
| 6/13/2012 | OUT | Cooper | Demoted to reserve roster | | | Before |
| 6/13/2012 | OUT | Cozart | Promoted to active roster | | | Before |
| 6/14/2012 | B C | Belt | Promoted to active roster | | | Before |
| 6/14/2012 | B C | Borbon | Demoted to reserve roster | | | Before |
| 6/14/2012 | B C | Morrison | Demoted to reserve roster | | | Before |
| 6/14/2012 | B C | Sweeney | Promoted to active roster | | | Before |
| 6/14/2012 | BOU | Leake | Demoted to reserve roster | | | Before |
| 6/14/2012 | BOU | Niemann | Promoted to active roster | | | Before |
| 6/14/2012 | DRI | Blackmon | Promoted to active roster | | | Before |
| 6/14/2012 | DRI | Callaspo | Promoted to active roster | | | Before |
| 6/14/2012 | DRI | Hinske | Demoted to reserve roster | | | Before |
| 6/14/2012 | DRI | Hinske | Promoted to active roster | | | Before |
| 6/14/2012 | DRI | Longoria | Demoted to reserve roster | | | Before |
| 6/14/2012 | DRI | Longoria | Promoted to active roster | | | Before |
| 6/14/2012 | DRI | Pagan | Demoted to reserve roster | | | Before |
| 6/14/2012 | DRI | Saltalamacchia | Demoted to reserve roster | | | Before |
| 6/14/2012 | FOR | Blum | Signed | | | Before |
| 6/14/2012 | FOR | Escobar,Y | Demoted to reserve roster | | | Before |
| 6/14/2012 | FOR | Escobar,Y | Promoted to active roster | | | Before |
| 6/14/2012 | FOR | Hernandez,D | Demoted to reserve roster | | | Before |
| 6/14/2012 | FOR | Maybin | Demoted to reserve roster | | | Before |
| 6/14/2012 | FOR | Seager | Promoted to active roster | | | Before |
| 6/14/2012 | FOR | Sutton | Released | | | Before |
| 6/14/2012 | FOR | Wilson,Br | Promoted to active roster | | | Before |
| 6/14/2012 | HSX | de Aza | Promoted to active roster | | | Before |
| 6/14/2012 | HSX | Morgan | Demoted to reserve roster | | | Before |
| 6/14/2012 | INP | Gillaspie | Demoted to reserve roster | | | Before |
| 6/14/2012 | INP | Valaika | Promoted to active roster | | | Before |
| 6/14/2012 | IRI | Ortiz,D | Promoted to active roster | | | Before |
| 6/14/2012 | IRI | Schumaker | Promoted to active roster | | | Before |
| 6/14/2012 | IRI | Utley | Demoted to reserve roster | | | Before |
| 6/14/2012 | IRI | Wright,D | Demoted to reserve roster | | | Before |
| 6/14/2012 | PEA | LeMahieu | Demoted to reserve roster | | | Before |
| 6/14/2012 | PEA | Patterson,E | Promoted to active roster | | | Before |
| 6/14/2012 | PHO | Colon | Demoted to reserve roster | | | Before |
| 6/14/2012 | PHO | Hawkins | Promoted to active roster | | | Before |
| 6/14/2012 | PHO | Lewis,C | Promoted to active roster | | | Before |
| 6/14/2012 | PHO | Posada | Promoted to active roster | | | Before |
| 6/14/2012 | PHO | Roberts,R | Demoted to reserve roster | | | Before |
| 6/14/2012 | PHO | Webb | Demoted to reserve roster | | | Before |
| 6/14/2012 | PIN | Arroyo | Promoted to active roster | | | Before |
| 6/14/2012 | PIN | Coleman,C | Demoted to reserve roster | | | Before |
| 6/14/2012 | PIN | Coleman,C | Promoted to active roster | | | Before |
| 6/14/2012 | PIN | Hafner | Demoted to reserve roster | | | Before |
| 6/14/2012 | PIN | Hafner | Promoted to active roster | | | Before |
| 6/14/2012 | PIN | Moseley | Demoted to reserve roster | | | Before |
| 6/14/2012 | PIN | Sanchez,F | Demoted to reserve roster | | | Before |
| 6/14/2012 | PIN | Sanchez,F | Promoted to active roster | | | Before |
| 6/14/2012 | PIN | Weiland | Demoted to reserve roster | | | Before |
| 6/14/2012 | PIN | Weiland | Promoted to active roster | | | Before |
| 6/14/2012 | QUI | Ackley | Promoted to active roster | | | Before |
| 6/14/2012 | QUI | Blanton | Demoted to reserve roster | | | Before |
| 6/14/2012 | QUI | Janssen | Promoted to active roster | | | Before |
| 6/14/2012 | QUI | Martinez,J | Promoted to active roster | | | Before |
| 6/14/2012 | QUI | Phelps | Demoted to reserve roster | | | Before |
| 6/14/2012 | QUI | Pie | Demoted to reserve roster | | | Before |
| 6/14/2012 | REB | Bedard | Promoted to active roster | | | Before |
| 6/14/2012 | REB | Ellis,A | Promoted to active roster | | | Before |
| 6/14/2012 | REB | Hairston,S | Demoted to reserve roster | | | Before |
| 6/14/2012 | REB | Johnson,Ji | Promoted to active roster | | | Before |
| 6/14/2012 | REB | Peavy | Demoted to reserve roster | | | Before |
| 6/14/2012 | REB | Perez,R | Demoted to reserve roster | | | Before |
| 6/14/2012 | REB | Perez,R | Promoted to active roster | | | Before |
| 6/14/2012 | REB | Torres,Al | Demoted to reserve roster | | | Before |
| 6/14/2012 | SCO | Latos | Promoted to active roster | | | Before |
| 6/14/2012 | SCO | Ross,T | Demoted to reserve roster | | | Before |
| 6/14/2012 | SKT | Nicasio | Demoted to reserve roster | | | Before |
| 6/14/2012 | SKT | Uggla | Promoted to active roster | | | Before |
| 6/14/2012 | SKT | Vargas | Promoted to active roster | | | Before |
| 6/14/2012 | SKT | Young,Mi | Demoted to reserve roster | | | Before |
| 6/15/2012 | DRI | Hinske | Released | | | Before |
| 6/15/2012 | DRI | Tateyama | Signed | | | Before |
| 6/15/2012 | EMP | Brach | Demoted to reserve roster | | | Before |
| 6/15/2012 | EMP | Darnell | Promoted to active roster | | | Before |
| 6/15/2012 | LEG | Carter | Demoted to reserve roster | | | Before |
| 6/15/2012 | LEG | Cishek | Promoted to active roster | | | Before |
| 6/15/2012 | LEG | Downs,M | Promoted to active roster | | | Before |
| 6/15/2012 | LEG | Jansen | Promoted to active roster | | | Before |
| 6/15/2012 | LEG | Morales,F | Demoted to reserve roster | | | Before |
| 6/15/2012 | LEG | Pelfrey | Promoted to active roster | | | Before |
| 6/15/2012 | LEG | Sanchez,J | Demoted to reserve roster | | | Before |
| 6/15/2012 | LEG | Spence | Demoted to reserve roster | | | Before |
| 6/15/2012 | MAI | Lucroy | Demoted to reserve roster | | | Before |
| 6/15/2012 | MAI | McGehee | Demoted to reserve roster | | | Before |
| 6/15/2012 | MAI | Molina,J | Promoted to active roster | | | Before |
| 6/15/2012 | MAI | Schlereth | Promoted to active roster | | | Before |
| 6/15/2012 | OUT | Ely | Released | | | Before |
| 6/15/2012 | OUT | Johnson,Ro | Signed | | | Before |
| 6/15/2012 | SKT | Badenhop | Promoted to active roster | | | Before |
| 6/15/2012 | SKT | Beato | Demoted to reserve roster | | | Before |
| 6/15/2012 | SKT | Gregerson | Demoted to reserve roster | | | Before |
| 6/15/2012 | SKT | Pestano | Promoted to active roster | | | Before |
| 6/20/2012 | DRI | LaHair | Acquired via trade | SLG | | After |
| 6/20/2012 | DRI | Rodriguez,FrJ | Traded away | SLG | | After |
| 6/20/2012 | EMP | Axelrod | Promoted to active roster | | | Before |
| 6/20/2012 | EMP | Braden | Demoted to reserve roster | | | Before |
| 6/20/2012 | EMP | Hendriks | Demoted to reserve roster | | | Before |
| 6/20/2012 | EMP | Ogando | Promoted to active roster | | | Before |
| 6/20/2012 | HSX | Blevins | Promoted to active roster | | | Before |
| 6/20/2012 | HSX | Farnsworth | Demoted to reserve roster | | | Before |
| 6/20/2012 | HSX | Gardner | Demoted to reserve roster | | | Before |
| 6/20/2012 | HSX | Lopez,W | Promoted to active roster | | | Before |
| 6/20/2012 | HSX | Morgan | Promoted to active roster | | | Before |
| 6/20/2012 | HSX | Patton | Demoted to reserve roster | | | Before |
| 6/20/2012 | PEA | LeMahieu | Promoted to active roster | | | Before |
| 6/20/2012 | PEA | Patterson,E | Demoted to reserve roster | | | Before |
| 6/20/2012 | REB | Hairston,S | Promoted to active roster | | | Before |
| 6/20/2012 | REB | Peavy | Promoted to active roster | | | Before |
| 6/20/2012 | REB | Soriano,R | Demoted to reserve roster | | | Before |
| 6/20/2012 | RLF | Dominguez | Promoted to active roster | | | Before |
| 6/20/2012 | RLF | Headley | Demoted to reserve roster | | | Before |
| 6/20/2012 | RLF | Lind | Demoted to reserve roster | | | Before |
| 6/20/2012 | RLF | Niese | Demoted to reserve roster | | | Before |
| 6/20/2012 | RLF | Sappelt | Promoted to active roster | | | Before |
| 6/20/2012 | RLF | Turner,Ja | Promoted to active roster | | | Before |
| 6/20/2012 | SLG | Mujica | Demoted to reserve roster | | | Before |
| 6/20/2012 | SLG | LaHair | Traded away | DRI | | After |
| 6/20/2012 | SLG | Rodriguez,FrJ | Acquired via trade | DRI | | After |
| 6/22/2012 | DRI | Bastardo | Demoted to reserve roster | | | Before |
| 6/22/2012 | DRI | Bastardo | Promoted to active roster | | | Before |
| 6/22/2012 | DRI | Blackmon | Demoted to reserve roster | | | Before |
| 6/22/2012 | DRI | Blackmon | Promoted to active roster | | | Before |
| 6/22/2012 | DRI | Giavotella | Demoted to reserve roster | | | Before |
| 6/22/2012 | DRI | LaHair | Promoted to active roster | | | Before |
| 6/22/2012 | DRI | McDonald,D | Demoted to reserve roster | | | Before |
| 6/22/2012 | DRI | Saltalamacchia | Promoted to active roster | | | Before |
| 6/22/2012 | EAG | Gregg | Demoted to reserve roster | | | Before |
| 6/22/2012 | EAG | Janish | Demoted to reserve roster | | | Before |
| 6/22/2012 | EAG | Kennedy,A | Promoted to active roster | | | Before |
| 6/22/2012 | EAG | Rodney | Promoted to active roster | | | Before |
| 6/22/2012 | INP | Betances | Promoted to active roster | | | Before |
| 6/22/2012 | INP | Gomes,B | Demoted to reserve roster | | | Before |
| 6/22/2012 | INP | Hundley | Demoted to reserve roster | | | Before |
| 6/22/2012 | INP | Pena,B | Promoted to active roster | | | Before |
| 6/22/2012 | MAI | Collmenter | Demoted to reserve roster | | | Before |
| 6/22/2012 | MAI | Galarraga | Promoted to active roster | | | Before |
| 6/22/2012 | OUT | Conger | Demoted to reserve roster | | | Before |
| 6/22/2012 | OUT | Cozart | Demoted to reserve roster | | | Before |
| 6/22/2012 | OUT | De Los Santos | Demoted to reserve roster | | | Before |
| 6/22/2012 | OUT | Dotel | Promoted to active roster | | | Before |
| 6/22/2012 | OUT | Hill,K | Signed | | | Before |
| 6/22/2012 | OUT | Lopez,R | Signed | | | Before |
| 6/22/2012 | OUT | McGee | Promoted to active roster | | | Before |
| 6/22/2012 | OUT | Perry | Released | | | Before |
| 6/22/2012 | OUT | Valbuena | Released | | | Before |
| 6/22/2012 | PEA | LeMahieu | Demoted to reserve roster | | | Before |
| 6/22/2012 | PEA | Patterson,E | Promoted to active roster | | | Before |
| 6/22/2012 | PHO | Arredondo | Promoted to active roster | | | Before |
| 6/22/2012 | PHO | Baker,Je | Promoted to active roster | | | Before |
| 6/22/2012 | PHO | Colon | Promoted to active roster | | | Before |
| 6/22/2012 | PHO | Duncan | Demoted to reserve roster | | | Before |
| 6/22/2012 | PHO | Keppinger | Demoted to reserve roster | | | Before |
| 6/22/2012 | PHO | Lewis,C | Demoted to reserve roster | | | Before |
| 6/22/2012 | PHO | Ludwick | Promoted to active roster | | | Before |
| 6/22/2012 | PHO | Posada | Demoted to reserve roster | | | Before |
| 6/22/2012 | PIN | Coleman,C | Promoted to active roster | | | Before |
| 6/22/2012 | PIN | Paulino,F | Demoted to reserve roster | | | Before |
| 6/22/2012 | PIN | Paulino,F | Promoted to active roster | | | Before |
| 6/22/2012 | PIN | Reddick | Demoted to reserve roster | | | Before |
| 6/22/2012 | PIN | Reddick | Promoted to active roster | | | Before |
| 6/22/2012 | PIN | Schierholtz | Demoted to reserve roster | | | Before |
| 6/22/2012 | PIN | Treanor | Demoted to reserve roster | | | Before |
| 6/22/2012 | PIN | Wilson,Bo | Promoted to active roster | | | Before |
| 6/22/2012 | PIN | Youkilis | Demoted to reserve roster | | | Before |
| 6/22/2012 | PIN | Youkilis | Promoted to active roster | | | Before |
| 6/22/2012 | REB | Ellis,A | Demoted to reserve roster | | | Before |
| 6/22/2012 | SCO | Castro,R | Promoted to active roster | | | Before |
| 6/22/2012 | SCO | Snyder,C | Demoted to reserve roster | | | Before |
| 6/22/2012 | SYN | Carreno | Demoted to reserve roster | | | Before |
| 6/22/2012 | SYN | Lindblom | Demoted to reserve roster | | | Before |
| 6/22/2012 | SYN | Peacock | Promoted to active roster | | | Before |
| 6/22/2012 | SYN | Rivera,Ma | Promoted to active roster | | | Before |
| 6/22/2012 | SYN | Uehara | Promoted to active roster | | | Before |
| 6/22/2012 | SYN | Worley | Demoted to reserve roster | | | Before |
| 6/26/2012 | EMP | Brach | Promoted to active roster | | | Before |
| 6/26/2012 | EMP | Reed,A | Demoted to reserve roster | | | Before |
| 6/26/2012 | EMP | Tomlin | Demoted to reserve roster | | | Before |
| 6/26/2012 | REB | Francis | Demoted to reserve roster | | | Before |
| 6/26/2012 | REB | Soriano,R | Promoted to active roster | | | Before |
| 6/27/2012 | EMP | Hunter,Tom | Released | | | Before |
| 6/27/2012 | EMP | Millwood | Signed | | | Before |
| 6/27/2012 | FOR | Blum | Demoted to reserve roster | | | Before |
| 6/27/2012 | FOR | Chapman | Demoted to reserve roster | | | Before |
| 6/27/2012 | FOR | Cobb | Promoted to active roster | | | Before |
| 6/27/2012 | FOR | Hernandez,D | Promoted to active roster | | | Before |
| 6/27/2012 | FOR | Kendrick,K | Demoted to reserve roster | | | Before |
| 6/27/2012 | FOR | Maybin | Promoted to active roster | | | Before |
| 6/27/2012 | FOR | Morton | Demoted to reserve roster | | | Before |
| 6/27/2012 | FOR | Nova | Promoted to active roster | | | Before |
| 6/27/2012 | FOR | Rzepczynski | Promoted to active roster | | | Before |
| 6/27/2012 | FOR | Wilson,Br | Demoted to reserve roster | | | Before |
| 6/27/2012 | OUT | Conger | Demoted to reserve roster | | | Before |
| 6/27/2012 | OUT | Conger | Promoted to active roster | | | Before |
| 6/27/2012 | OUT | Kottaras | Demoted to reserve roster | | | Before |
| 6/27/2012 | REB | Crow | Demoted to reserve roster | | | Before |
| 6/27/2012 | REB | Grilli | Signed | | | Before |
| 6/27/2012 | REB | Nishioka | Released | | | Before |
| 6/27/2012 | RLF | Dominguez | Demoted to reserve roster | | | Before |
| 6/27/2012 | RLF | Headley | Promoted to active roster | | | Before |
| 6/27/2012 | SLG | Benoit | Demoted to reserve roster | | | Before |
| 6/27/2012 | SLG | Boggs,M | Promoted to active roster | | | Before |
| 6/27/2012 | SLG | Devine | Released | | | Before |
| 6/27/2012 | SLG | Greene | Promoted to active roster | | | Before |
| 6/27/2012 | SLG | Jurrjens | Demoted to reserve roster | | | Before |
| 6/27/2012 | SLG | Kelley | Signed | | | Before |
| 6/27/2012 | SLG | Lindstrom | Demoted to reserve roster | | | Before |
| 6/27/2012 | SLG | Lynn | Promoted to active roster | | | Before |
| 6/27/2012 | SLG | Madson | Demoted to reserve roster | | | Before |
| 6/27/2012 | SLG | Mujica | Promoted to active roster | | | Before |
| 6/27/2012 | SLG | Presley | Demoted to reserve roster | | | Before |
| 6/27/2012 | SLG | Salas | Demoted to reserve roster | | | Before |
| 6/27/2012 | SLG | Scutaro | Demoted to reserve roster | | | Before |
| 6/27/2012 | SLG | Venable | Promoted to active roster | | | Before |
| 6/27/2012 | SYN | Beachy | Promoted to active roster | | | Before |
| 6/27/2012 | SYN | Carreno | Promoted to active roster | | | Before |
| 6/27/2012 | SYN | Eovaldi | Demoted to reserve roster | | | Before |
| 6/27/2012 | SYN | Minor | Demoted to reserve roster | | | Before |
| 6/27/2012 | SYN | Peacock | Demoted to reserve roster | | | Before |
| 6/27/2012 | SYN | Worley | Promoted to active roster | | | Before |
| 6/28/2012 | B C | Belt | Demoted to reserve roster | | | Before |
| 6/28/2012 | B C | Cecil | Promoted to active roster | | | Before |
| 6/28/2012 | B C | Furbush | Demoted to reserve roster | | | Before |
| 6/28/2012 | B C | Gomez,C | Demoted to reserve roster | | | Before |
| 6/28/2012 | B C | Hochevar | Demoted to reserve roster | | | Before |
| 6/28/2012 | B C | LaPorta | Promoted to active roster | | | Before |
| 6/28/2012 | B C | Morel | Demoted to reserve roster | | | Before |
| 6/28/2012 | B C | Prado | Promoted to active roster | | | Before |
| 6/28/2012 | B C | Upton,J | Promoted to active roster | | | Before |
| 6/28/2012 | B C | Ziegler | Promoted to active roster | | | Before |
| 6/28/2012 | PHO | Arredondo | Demoted to reserve roster | | | Before |
| 6/28/2012 | PHO | Duncan | Promoted to active roster | | | Before |
| 6/28/2012 | PHO | Keppinger | Demoted to reserve roster | | | Before |
| 6/28/2012 | PHO | Keppinger | Promoted to active roster | | | Before |
| 6/28/2012 | PHO | Ludwick | Demoted to reserve roster | | | Before |
| 6/28/2012 | PHO | Posada | Promoted to active roster | | | Before |
| 6/28/2012 | PHO | Roberts,R | Demoted to reserve roster | | | Before |
| 6/28/2012 | PHO | Roberts,R | Promoted to active roster | | | Before |
| 6/28/2012 | SKT | Johnson,Re | Demoted to reserve roster | | | Before |
| 6/28/2012 | SKT | Johnson,Re | Promoted to active roster | | | Before |
| 6/28/2012 | SKT | Overbay | Demoted to reserve roster | | | Before |
| 6/28/2012 | SKT | Span | Demoted to reserve roster | | | Before |
| 6/28/2012 | SKT | Span | Promoted to active roster | | | Before |
| 6/28/2012 | SKT | Young,Mi | Promoted to active roster | | | Before |
| 7/2/2012 | REB | Bedard | Demoted to reserve roster | | | Before |
| 7/2/2012 | REB | Crow | Promoted to active roster | | | Before |
| 7/2/2012 | REB | Francis | Promoted to active roster | | | Before |
| 7/2/2012 | REB | Soriano,R | Demoted to reserve roster | | | Before |
| 7/3/2012 | B C | Morrison | Promoted to active roster | | | Before |
| 7/3/2012 | B C | Reimold | Demoted to reserve roster | | | Before |
| 7/3/2012 | COM | Balester | Promoted to active roster | | | Before |
| 7/3/2012 | COM | Nunez,L | Demoted to reserve roster | | | Before |
| 7/3/2012 | DRI | LaHair | Demoted to reserve roster | | | Before |
| 7/3/2012 | DRI | LaHair | Promoted to active roster | | | Before |
| 7/3/2012 | DRI | Tateyama | Promoted to active roster | | | Before |
| 7/3/2012 | DRI | Varitek | Demoted to reserve roster | | | Before |
| 7/3/2012 | EAG | Beavan | Promoted to active roster | | | Before |
| 7/3/2012 | EAG | Bell,H | Demoted to reserve roster | | | Before |
| 7/3/2012 | EAG | Campana | Promoted to active roster | | | Before |
| 7/3/2012 | EAG | Capps | Promoted to active roster | | | Before |
| 7/3/2012 | EAG | Coleman,L | Demoted to reserve roster | | | Before |
| 7/3/2012 | EAG | Gregg | Promoted to active roster | | | Before |
| 7/3/2012 | EAG | Moscoso | Demoted to reserve roster | | | Before |
| 7/3/2012 | EAG | Parra | Demoted to reserve roster | | | Before |
| 7/3/2012 | EMP | Brach | Demoted to reserve roster | | | Before |
| 7/3/2012 | EMP | Darnell | Demoted to reserve roster | | | Before |
| 7/3/2012 | EMP | Reed,A | Promoted to active roster | | | Before |
| 7/3/2012 | EMP | Reyes,JJ | Released | | | Before |
| 7/3/2012 | EMP | Rowand | Signed | | | Before |
| 7/3/2012 | EMP | Towles | Released | | | Before |
| 7/3/2012 | EMP | Westbrook | Promoted to active roster | | | Before |
| 7/3/2012 | EMP | Westbrook | Acquired via trade | SLG | | After |
| 7/3/2012 | FOR | Blum | Promoted to active roster | | | Before |
| 7/3/2012 | FOR | Chapman | Promoted to active roster | | | Before |
| 7/3/2012 | FOR | Dirks | Demoted to reserve roster | | | Before |
| 7/3/2012 | FOR | Francisco,J | Promoted to active roster | | | Before |
| 7/3/2012 | FOR | Morton | Promoted to active roster | | | Before |
| 7/3/2012 | FOR | Richard | Demoted to reserve roster | | | Before |
| 7/3/2012 | FOR | Rzepczynski | Demoted to reserve roster | | | Before |
| 7/3/2012 | FOR | Sale | Demoted to reserve roster | | | Before |
| 7/3/2012 | FOR | Seager | Demoted to reserve roster | | | Before |
| 7/3/2012 | FOR | Wilson,Br | Promoted to active roster | | | Before |
| 7/3/2012 | HSX | Arencibia | Demoted to reserve roster | | | Before |
| 7/3/2012 | HSX | Blevins | Promoted to active roster | | | Before |
| 7/3/2012 | HSX | Capuano | Promoted to active roster | | | Before |
| 7/3/2012 | HSX | Cordero | Demoted to reserve roster | | | Before |
| 7/3/2012 | HSX | Flowers | Promoted to active roster | | | Before |
| 7/3/2012 | HSX | Gardner | Demoted to reserve roster | | | Before |
| 7/3/2012 | HSX | Lopez,W | Promoted to active roster | | | Before |
| 7/3/2012 | HSX | Morgan | Promoted to active roster | | | Before |
| 7/3/2012 | HSX | Patton | Demoted to reserve roster | | | Before |
| 7/3/2012 | HSX | Porcello | Demoted to reserve roster | | | Before |
| 7/3/2012 | INP | Betances | Demoted to reserve roster | | | Before |
| 7/3/2012 | INP | McAllister | Demoted to reserve roster | | | Before |
| 7/3/2012 | INP | Paul | Promoted to active roster | | | Before |
| 7/3/2012 | INP | Schafer,L | Promoted to active roster | | | Before |
| 7/3/2012 | IRI | Coghlan | Demoted to reserve roster | | | Before |
| 7/3/2012 | IRI | MacDougal | Released | | | Before |
| 7/3/2012 | IRI | Schumaker | Demoted to reserve roster | | | Before |
| 7/3/2012 | IRI | Utley | Promoted to active roster | | | Before |
| 7/3/2012 | IRI | Wright,D | Promoted to active roster | | | Before |
| 7/3/2012 | IRI | Lind | Acquired via trade | RLF | | After |
| 7/3/2012 | LEG | Boesch | Demoted to reserve roster | | | Before |
| 7/3/2012 | LEG | Carp | Promoted to active roster | | | Before |
| 7/3/2012 | LEG | Cishek | Demoted to reserve roster | | | Before |
| 7/3/2012 | LEG | Cueto | Demoted to reserve roster | | | Before |
| 7/3/2012 | LEG | Gutierrez,J | Promoted to active roster | | | Before |
| 7/3/2012 | LEG | Hand | Demoted to reserve roster | | | Before |
| 7/3/2012 | LEG | Jansen | Demoted to reserve roster | | | Before |
| 7/3/2012 | LEG | Morales,F | Promoted to active roster | | | Before |
| 7/3/2012 | LEG | Pineda | Demoted to reserve roster | | | Before |
| 7/3/2012 | LEG | Sanchez,J | Promoted to active roster | | | Before |
| 7/3/2012 | LEG | Takahashi | Promoted to active roster | | | Before |
| 7/3/2012 | LEG | Volstad | Promoted to active roster | | | Before |
| 7/3/2012 | MAI | Collmenter | Promoted to active roster | | | Before |
| 7/3/2012 | MAI | Downs,S | Demoted to reserve roster | | | Before |
| 7/3/2012 | MAI | Downs,S | Promoted to active roster | | | Before |
| 7/3/2012 | MAI | Galarraga | Demoted to reserve roster | | | Before |
| 7/3/2012 | MAI | Lucroy | Promoted to active roster | | | Before |
| 7/3/2012 | MAI | McClendon | Released | | | Before |
| 7/3/2012 | MAI | Molina,J | Demoted to reserve roster | | | Before |
| 7/3/2012 | MAI | Schlereth | Demoted to reserve roster | | | Before |
| 7/3/2012 | MAI | Varvaro | Signed | | | Before |
| 7/3/2012 | OUT | Allen | Released | | | Before |
| 7/3/2012 | OUT | Cooper | Demoted to reserve roster | | | Before |
| 7/3/2012 | OUT | Cooper | Promoted to active roster | | | Before |
| 7/3/2012 | OUT | Elbert | Demoted to reserve roster | | | Before |
| 7/3/2012 | OUT | Harris | Signed | | | Before |
| 7/3/2012 | PEA | Duda | Promoted to active roster | | | Before |
| 7/3/2012 | PEA | Morneau | Demoted to reserve roster | | | Before |
| 7/3/2012 | PHO | Abreu,B | Promoted to active roster | | | Before |
| 7/3/2012 | PHO | Fuentes | Promoted to active roster | | | Before |
| 7/3/2012 | PHO | Humber | Demoted to reserve roster | | | Before |
| 7/3/2012 | PHO | Johnson,C | Demoted to reserve roster | | | Before |
| 7/3/2012 | PHO | Johnson,C | Promoted to active roster | | | Before |
| 7/3/2012 | PHO | Johnson,C | Demoted to reserve roster | | | Before |
| 7/3/2012 | PHO | Keppinger | Promoted to active roster | | | Before |
| 7/3/2012 | PHO | Kinsler | Demoted to reserve roster | | | Before |
| 7/3/2012 | PHO | Kubel | Demoted to reserve roster | | | Before |
| 7/3/2012 | PHO | Lewis,C | Promoted to active roster | | | Before |
| 7/3/2012 | PHO | Martinez,C | Demoted to reserve roster | | | Before |
| 7/3/2012 | PHO | Roberts,R | Promoted to active roster | | | Before |
| 7/3/2012 | PIN | Ankiel | Demoted to reserve roster | | | Before |
| 7/3/2012 | PIN | Arroyo | Demoted to reserve roster | | | Before |
| 7/3/2012 | PIN | Davis,I | Promoted to active roster | | | Before |
| 7/3/2012 | PIN | Diaz | Demoted to reserve roster | | | Before |
| 7/3/2012 | PIN | Furcal | Demoted to reserve roster | | | Before |
| 7/3/2012 | PIN | Hafner | Demoted to reserve roster | | | Before |
| 7/3/2012 | PIN | Hafner | Promoted to active roster | | | Before |
| 7/3/2012 | PIN | Hafner | Promoted to active roster | | | Before |
| 7/3/2012 | PIN | Reddick | Promoted to active roster | | | Before |
| 7/3/2012 | PIN | Sanchez,F | Demoted to reserve roster | | | Before |
| 7/3/2012 | PIN | Sanchez,F | Promoted to active roster | | | Before |
| 7/3/2012 | PIN | Schierholtz | Promoted to active roster | | | Before |
| 7/3/2012 | PIN | Treanor | Promoted to active roster | | | Before |
| 7/3/2012 | PIN | Weiland | Promoted to active roster | | | Before |
| 7/3/2012 | PIN | Wilson,Bo | Demoted to reserve roster | | | Before |
| 7/3/2012 | PIN | Youkilis | Demoted to reserve roster | | | Before |
| 7/3/2012 | RLF | Cameron | Signed | | | Before |
| 7/3/2012 | RLF | Cameron | Demoted to reserve roster | | | Before |
| 7/3/2012 | RLF | Cameron | Promoted to active roster | | | Before |
| 7/3/2012 | RLF | Snider | Demoted to reserve roster | | | Before |
| 7/3/2012 | RLF | Teheran | Demoted to reserve roster | | | Before |
| 7/3/2012 | RLF | Teheran | Promoted to active roster | | | Before |
| 7/3/2012 | RLF | Lind | Traded away | IRI | | After |
| 7/3/2012 | SLG | Eveland | Signed | | | Before |
| 7/3/2012 | SLG | Eveland | Demoted to reserve roster | | | Before |
| 7/3/2012 | SLG | Jurrjens | Promoted to active roster | | | Before |
| 7/3/2012 | SLG | Kelley | Demoted to reserve roster | | | Before |
| 7/3/2012 | SLG | Lynn | Demoted to reserve roster | | | Before |
| 7/3/2012 | SLG | Madson | Promoted to active roster | | | Before |
| 7/3/2012 | SLG | Salas | Promoted to active roster | | | Before |
| 7/3/2012 | SLG | Westbrook | Traded away | EMP | | After |
| 7/3/2012 | SYN | Hammel | Demoted to reserve roster | | | Before |
| 7/3/2012 | SYN | Minor | Promoted to active roster | | | Before |
| 7/4/2012 | HSX | Arencibia | Promoted to active roster | | | Before |
| 7/4/2012 | HSX | de Aza | Demoted to reserve roster | | | Before |
| 7/4/2012 | HSX | Flowers | Demoted to reserve roster | | | Before |
| 7/4/2012 | HSX | Gardner | Promoted to active roster | | | Before |
| 7/4/2012 | SCO | Castro,R | Demoted to reserve roster | | | Before |
| 7/4/2012 | SCO | Snyder,C | Promoted to active roster | | | Before |
| 7/4/2012 | SKT | Beato | Promoted to active roster | | | Before |
| 7/4/2012 | SKT | Johnson,Re | Demoted to reserve roster | | | Before |
| 7/4/2012 | SKT | Matsuzaka | Promoted to active roster | | | Before |
| 7/4/2012 | SKT | Pavano | Demoted to reserve roster | | | Before |
| 7/4/2012 | SKT | Span | Promoted to active roster | | | Before |
| 7/4/2012 | SKT | Wright,J | Demoted to reserve roster | | | Before |
| 7/5/2012 | DRI | Thome | Demoted to reserve roster | | | Before |
| 7/5/2012 | DRI | Varitek | Promoted to active roster | | | Before |
| 7/8/2012 | FOR | Blum | Released | | | Before |
| 7/8/2012 | FOR | Hinske | Signed | | | Before |
| 7/9/2012 | B C | Floyd | Demoted to reserve roster | | | Before |
| 7/9/2012 | B C | Furbush | Promoted to active roster | | | Before |
| 7/9/2012 | B C | Gomez,C | Promoted to active roster | | | Before |
| 7/9/2012 | B C | Masset | Promoted to active roster | | | Before |
| 7/9/2012 | B C | Scherzer | Demoted to reserve roster | | | Before |
| 7/9/2012 | B C | Sogard | Promoted to active roster | | | Before |
| 7/9/2012 | B C | Sweeney | Demoted to reserve roster | | | Before |
| 7/9/2012 | B C | Young,E | Demoted to reserve roster | | | Before |
| 7/9/2012 | COM | Balester | Demoted to reserve roster | | | Before |
| 7/9/2012 | COM | Nunez,L | Promoted to active roster | | | Before |
| 7/9/2012 | EMP | Axelrod | Demoted to reserve roster | | | Before |
| 7/9/2012 | EMP | Milone | Promoted to active roster | | | Before |
| 7/9/2012 | FOR | Blum | Released | | | Before |
| 7/9/2012 | FOR | Blum | Signed | | | Before |
| 7/9/2012 | FOR | Cobb | Demoted to reserve roster | | | Before |
| 7/9/2012 | FOR | Hinske | Released | | | Before |
| 7/9/2012 | FOR | Hinske | Signed | | | Before |
| 7/9/2012 | FOR | Richard | Promoted to active roster | | | Before |
| 7/9/2012 | FOR | Rzepczynski | Promoted to active roster | | | Before |
| 7/9/2012 | FOR | Wilson,Br | Demoted to reserve roster | | | Before |
| 7/9/2012 | MAI | Collmenter | Demoted to reserve roster | | | Before |
| 7/9/2012 | MAI | Donald | Promoted to active roster | | | Before |
| 7/9/2012 | MAI | Downs,S | Demoted to reserve roster | | | Before |
| 7/9/2012 | MAI | Greinke | Demoted to reserve roster | | | Before |
| 7/9/2012 | MAI | Harrison,J | Demoted to reserve roster | | | Before |
| 7/9/2012 | MAI | Huff,D | Promoted to active roster | | | Before |
| 7/9/2012 | MAI | Patterson,C | Promoted to active roster | | | Before |
| 7/9/2012 | MAI | Wood,Tr | Promoted to active roster | | | Before |
| 7/9/2012 | PHO | Abreu,B | Demoted to reserve roster | | | Before |
| 7/9/2012 | PHO | Baker,Je | Demoted to reserve roster | | | Before |
| 7/9/2012 | PHO | Humber | Promoted to active roster | | | Before |
| 7/9/2012 | PHO | Kinsler | Promoted to active roster | | | Before |
| 7/9/2012 | PHO | Kubel | Promoted to active roster | | | Before |
| 7/9/2012 | PHO | Lewis,C | Demoted to reserve roster | | | Before |
| 7/9/2012 | PHO | Loe | Demoted to reserve roster | | | Before |
| 7/9/2012 | PHO | Martinez,C | Promoted to active roster | | | Before |
| 7/9/2012 | PIN | Arroyo | Promoted to active roster | | | Before |
| 7/9/2012 | PIN | Cain,L | Promoted to active roster | | | Before |
| 7/9/2012 | PIN | Cassevah | Demoted to reserve roster | | | Before |
| 7/9/2012 | PIN | Davis,I | Demoted to reserve roster | | | Before |
| 7/9/2012 | PIN | Davis,R | Demoted to reserve roster | | | Before |
| 7/9/2012 | PIN | Diaz | Promoted to active roster | | | Before |
| 7/9/2012 | PIN | Furcal | Promoted to active roster | | | Before |
| 7/9/2012 | PIN | Logan | Demoted to reserve roster | | | Before |
| 7/9/2012 | PIN | Logan | Promoted to active roster | | | Before |
| 7/9/2012 | PIN | Sanchez,F | Demoted to reserve roster | | | Before |
| 7/9/2012 | PIN | Treanor | Demoted to reserve roster | | | Before |
| 7/9/2012 | PIN | Wakefield | Demoted to reserve roster | | | Before |
| 7/9/2012 | PIN | Wilson,Bo | Promoted to active roster | | | Before |
| 7/9/2012 | PIN | Youkilis | Promoted to active roster | | | Before |
| 7/9/2012 | QUI | Ackley | Demoted to reserve roster | | | Before |
| 7/9/2012 | QUI | Ackley | Promoted to active roster | | | Before |
| 7/9/2012 | QUI | Bell,J | Promoted to active roster | | | Before |
| 7/9/2012 | QUI | Crawford,B | Demoted to reserve roster | | | Before |
| 7/9/2012 | QUI | Garcia,F | Promoted to active roster | | | Before |
| 7/9/2012 | QUI | Harden | Demoted to reserve roster | | | Before |
| 7/9/2012 | QUI | Lombardozzi | Demoted to reserve roster | | | Before |
| 7/9/2012 | QUI | Lombardozzi | Promoted to active roster | | | Before |
| 7/9/2012 | QUI | Martinez,J | Demoted to reserve roster | | | Before |
| 7/9/2012 | QUI | Montero,J | Promoted to active roster | | | Before |
| 7/9/2012 | REB | Bedard | Promoted to active roster | | | Before |
| 7/9/2012 | REB | Bray | Demoted to reserve roster | | | Before |
| 7/9/2012 | REB | Ellis,A | Promoted to active roster | | | Before |
| 7/9/2012 | REB | Grilli | Demoted to reserve roster | | | Before |
| 7/9/2012 | REB | Hairston,S | Demoted to reserve roster | | | Before |
| 7/9/2012 | REB | Peavy | Demoted to reserve roster | | | Before |
| 7/9/2012 | REB | Perez,R | Demoted to reserve roster | | | Before |
| 7/9/2012 | REB | Soriano,R | Promoted to active roster | | | Before |
| 7/9/2012 | REB | Torres,Al | Promoted to active roster | | | Before |
| 7/9/2012 | REB | Wilhelmsen | Promoted to active roster | | | Before |
| 7/9/2012 | RLF | Robinson,T | Demoted to reserve roster | | | Before |
| 7/9/2012 | RLF | Teheran | Promoted to active roster | | | Before |
| 7/9/2012 | RLF | Tosoni | Promoted to active roster | | | Before |
| 7/9/2012 | RLF | Turner,Ja | Demoted to reserve roster | | | Before |
| 7/9/2012 | SCO | Carrasco,C | Promoted to active roster | | | Before |
| 7/9/2012 | SCO | Castro,R | Promoted to active roster | | | Before |
| 7/9/2012 | SCO | Craig | Promoted to active roster | | | Before |
| 7/9/2012 | SCO | Drabek | Demoted to reserve roster | | | Before |
| 7/9/2012 | SCO | Guzman | Demoted to reserve roster | | | Before |
| 7/9/2012 | SCO | McCarthy | Demoted to reserve roster | | | Before |
| 7/9/2012 | SCO | Ross,T | Promoted to active roster | | | Before |
| 7/9/2012 | SCO | Snyder,C | Demoted to reserve roster | | | Before |
| 7/9/2012 | SID | Ondrusek | Demoted to reserve roster | | | Before |
| 7/9/2012 | SID | Parnell | Promoted to active roster | | | Before |
| 7/9/2012 | SKT | Badenhop | Demoted to reserve roster | | | Before |
| 7/9/2012 | SKT | Gregerson | Promoted to active roster | | | Before |
| 7/9/2012 | SKT | Matsuzaka | Demoted to reserve roster | | | Before |
| 7/9/2012 | SKT | Pavano | Promoted to active roster | | | Before |
| 7/9/2012 | SLG | Beckett | Demoted to reserve roster | | | Before |
| 7/9/2012 | SLG | Brignac | Promoted to active roster | | | Before |
| 7/9/2012 | SLG | Eveland | Promoted to active roster | | | Before |
| 7/9/2012 | SLG | Greene | Demoted to reserve roster | | | Before |
| 7/9/2012 | SLG | Ibanez | Demoted to reserve roster | | | Before |
| 7/9/2012 | SLG | Kelley | Promoted to active roster | | | Before |
| 7/9/2012 | SLG | Madson | Demoted to reserve roster | | | Before |
| 7/9/2012 | SLG | Presley | Promoted to active roster | | | Before |
| 7/9/2012 | SYN | Bailey,H | Promoted to active roster | | | Before |
| 7/9/2012 | SYN | Beachy | Demoted to reserve roster | | | Before |
| 7/9/2012 | SYN | Beachy | Promoted to active roster | | | Before |
| 7/9/2012 | SYN | Hammel | Promoted to active roster | | | Before |
| 7/9/2012 | SYN | Minor | Demoted to reserve roster | | | Before |
| 7/9/2012 | SYN | Worley | Demoted to reserve roster | | | Before |
| 7/10/2012 | LEG | Adcock | Demoted to reserve roster | | | Before |
| 7/10/2012 | LEG | Boesch | Promoted to active roster | | | Before |
| 7/10/2012 | LEG | Cueto | Promoted to active roster | | | Before |
| 7/10/2012 | LEG | Jansen | Promoted to active roster | | | Before |
| 7/10/2012 | LEG | Jennings | Demoted to reserve roster | | | Before |
| 7/10/2012 | LEG | Pineda | Promoted to active roster | | | Before |
| 7/10/2012 | LEG | Sanchez,J | Demoted to reserve roster | | | Before |
| 7/10/2012 | LEG | Volstad | Demoted to reserve roster | | | Before |
| 7/14/2012 | REB | Alvarez,P | Demoted to reserve roster | | | Before |
| 7/14/2012 | REB | Bray | Promoted to active roster | | | Before |
| 7/14/2012 | REB | Carmona | Demoted to reserve roster | | | Before |
| 7/14/2012 | REB | Crow | Demoted to reserve roster | | | Before |
| 7/14/2012 | REB | Hairston,S | Promoted to active roster | | | Before |
| 7/14/2012 | REB | Johnson,Jo | Promoted to active roster | | | Before |
| 7/14/2012 | REB | Perez,R | Promoted to active roster | | | Before |
| 7/14/2012 | REB | Torres,Al | Demoted to reserve roster | | | Before |
| 7/15/2012 | B C | Floyd | Promoted to active roster | | | Before |
| 7/15/2012 | B C | Matusz | Demoted to reserve roster | | | Before |
| 7/15/2012 | B C | Morel | Promoted to active roster | | | Before |
| 7/15/2012 | B C | Sizemore,S | Demoted to reserve roster | | | Before |
| 7/15/2012 | B C | Sizemore,S | Promoted to active roster | | | Before |
| 7/15/2012 | B C | Sogard | Demoted to reserve roster | | | Before |
| 7/15/2012 | DRI | Choate | Signed | | | Before |
| 7/15/2012 | DRI | Satin | Released | | | Before |
| 7/15/2012 | DRI | Bay | Acquired via trade | QUI | | After |
| 7/15/2012 | DRI | Marrero | Traded away | QUI | | After |
| 7/15/2012 | EMP | Fiers | Promoted to active roster | | | Before |
| 7/15/2012 | HSX | Burnett,AJ | Promoted to active roster | | | Before |
| 7/15/2012 | HSX | Cordero | Promoted to active roster | | | Before |
| 7/15/2012 | HSX | Farnsworth | Demoted to reserve roster | | | Before |
| 7/15/2012 | HSX | Gee | Demoted to reserve roster | | | Before |
| 7/15/2012 | MAI | Donald | Demoted to reserve roster | | | Before |
| 7/15/2012 | MAI | Galarraga | Promoted to active roster | | | Before |
| 7/15/2012 | MAI | Maholm | Demoted to reserve roster | | | Before |
| 7/15/2012 | MAI | Saito | Promoted to active roster | | | Before |
| 7/15/2012 | PEA | LeMahieu | Promoted to active roster | | | Before |
| 7/15/2012 | PEA | Patterson,E | Demoted to reserve roster | | | Before |
| 7/15/2012 | PHO | Arredondo | Promoted to active roster | | | Before |
| 7/15/2012 | PHO | Baker,Je | Promoted to active roster | | | Before |
| 7/15/2012 | PHO | Carpenter,CJ | Released | | | Before |
| 7/15/2012 | PHO | Carpenter,CJ | Released | | | Before |
| 7/15/2012 | PHO | Carpenter,CJ | Signed | | | Before |
| 7/15/2012 | PHO | Colon | Demoted to reserve roster | | | Before |
| 7/15/2012 | PHO | Fuentes | Demoted to reserve roster | | | Before |
| 7/15/2012 | PHO | Johnson,E | Signed | | | Before |
| 7/15/2012 | PHO | Johnson,E | Demoted to reserve roster | | | Before |
| 7/15/2012 | PHO | Johnson,E | Promoted to active roster | | | Before |
| 7/15/2012 | PHO | Keppinger | Demoted to reserve roster | | | Before |
| 7/15/2012 | PHO | Lewis,C | Promoted to active roster | | | Before |
| 7/15/2012 | PHO | Punto | Demoted to reserve roster | | | Before |
| 7/15/2012 | PIN | Cain,L | Demoted to reserve roster | | | Before |
| 7/15/2012 | PIN | Coleman,C | Demoted to reserve roster | | | Before |
| 7/15/2012 | PIN | Davis,R | Promoted to active roster | | | Before |
| 7/15/2012 | PIN | Moseley | Promoted to active roster | | | Before |
| 7/15/2012 | PIN | Wakefield | Promoted to active roster | | | Before |
| 7/15/2012 | PIN | Weiland | Demoted to reserve roster | | | Before |
| 7/15/2012 | QUI | Bay | Traded away | DRI | | After |
| 7/15/2012 | QUI | Marrero | Acquired via trade | DRI | | After |
| 7/15/2012 | REB | Bedard | Demoted to reserve roster | | | Before |
| 7/15/2012 | REB | Peavy | Promoted to active roster | | | Before |
| 7/15/2012 | RLF | Alonso | Demoted to reserve roster | | | Before |
| 7/15/2012 | RLF | Dominguez | Promoted to active roster | | | Before |
| 7/15/2012 | SCO | Helton | Demoted to reserve roster | | | Before |
| 7/15/2012 | SCO | Parmelee | Promoted to active roster | | | Before |
| 7/15/2012 | SKT | Damon | Demoted to reserve roster | | | Before |
| 7/15/2012 | SKT | Johnson,Re | Promoted to active roster | | | Before |
| 7/15/2012 | SLG | Beckett | Promoted to active roster | | | Before |
| 7/15/2012 | SLG | Benoit | Promoted to active roster | | | Before |
| 7/15/2012 | SLG | Boggs,M | Demoted to reserve roster | | | Before |
| 7/15/2012 | SLG | Brignac | Demoted to reserve roster | | | Before |
| 7/15/2012 | SLG | Kelley | Demoted to reserve roster | | | Before |
| 7/15/2012 | SLG | Madson | Promoted to active roster | | | Before |
| 7/15/2012 | SLG | Mujica | Demoted to reserve roster | | | Before |
| 7/15/2012 | SLG | Mujica | Promoted to active roster | | | Before |
| 7/15/2012 | SLG | Scutaro | Promoted to active roster | | | Before |
| 7/15/2012 | SLG | Vogelsong | Demoted to reserve roster | | | Before |
| 7/15/2012 | SYN | Carreno | Demoted to reserve roster | | | Before |
| 7/15/2012 | SYN | Worley | Promoted to active roster | | | Before |
| 7/16/2012 | FOR | Cobb | Promoted to active roster | | | Before |
| 7/16/2012 | FOR | Dirks | Promoted to active roster | | | Before |
| 7/16/2012 | FOR | Francisco,J | Demoted to reserve roster | | | Before |
| 7/16/2012 | FOR | Goldschmidt | Promoted to active roster | | | Before |
| 7/16/2012 | FOR | Lowe,M | Demoted to reserve roster | | | Before |
| 7/16/2012 | FOR | Marquis | Demoted to reserve roster | | | Before |
| 7/16/2012 | FOR | Wallace | Demoted to reserve roster | | | Before |
| 7/16/2012 | FOR | Wilson,Br | Promoted to active roster | | | Before |
| 7/21/2012 | DRI | Nicasio | Acquired via trade | SKT | | After |
| 7/21/2012 | REB | Alvarez,P | Promoted to active roster | | | Before |
| 7/21/2012 | REB | Bedard | Promoted to active roster | | | Before |
| 7/21/2012 | REB | Carmona | Promoted to active roster | | | Before |
| 7/21/2012 | REB | Crow | Promoted to active roster | | | Before |
| 7/21/2012 | REB | Ellis,A | Demoted to reserve roster | | | Before |
| 7/21/2012 | REB | Johnson,Jo | Demoted to reserve roster | | | Before |
| 7/21/2012 | REB | Peavy | Demoted to reserve roster | | | Before |
| 7/21/2012 | REB | Soriano,R | Demoted to reserve roster | | | Before |
| 7/21/2012 | SKT | Nicasio | Traded away | DRI | | After |
| 7/23/2012 | B C | Flores | Demoted to reserve roster | | | Before |
| 7/23/2012 | B C | Floyd | Demoted to reserve roster | | | Before |
| 7/23/2012 | B C | Scherzer | Promoted to active roster | | | Before |
| 7/23/2012 | B C | Sogard | Promoted to active roster | | | Before |
| 7/23/2012 | DRI | Navarro,Y | Released | | | Before |
| 7/23/2012 | EAG | Beavan | Demoted to reserve roster | | | Before |
| 7/23/2012 | EAG | Bell,H | Promoted to active roster | | | Before |
| 7/23/2012 | EAG | Brantley | Demoted to reserve roster | | | Before |
| 7/23/2012 | EAG | Capps | Demoted to reserve roster | | | Before |
| 7/23/2012 | EAG | Moscoso | Promoted to active roster | | | Before |
| 7/23/2012 | EAG | Parra | Promoted to active roster | | | Before |
| 7/23/2012 | EMP | Frazier | Demoted to reserve roster | | | Before |
| 7/23/2012 | EMP | Tomlin | Promoted to active roster | | | Before |
| 7/23/2012 | FOR | Chapman | Demoted to reserve roster | | | Before |
| 7/23/2012 | FOR | Goldschmidt | Demoted to reserve roster | | | Before |
| 7/23/2012 | FOR | Kendrick,K | Promoted to active roster | | | Before |
| 7/23/2012 | FOR | Laird,G | Signed | | | Before |
| 7/23/2012 | FOR | Lowe,M | Demoted to reserve roster | | | Before |
| 7/23/2012 | FOR | Lowe,M | Promoted to active roster | | | Before |
| 7/23/2012 | FOR | Marquis | Promoted to active roster | | | Before |
| 7/23/2012 | FOR | Posey | Demoted to reserve roster | | | Before |
| 7/23/2012 | FOR | Richard | Demoted to reserve roster | | | Before |
| 7/23/2012 | FOR | Sale | Promoted to active roster | | | Before |
| 7/23/2012 | FOR | Wallace | Promoted to active roster | | | Before |
| 7/23/2012 | FOR | Willis | Released | | | Before |
| 7/23/2012 | FOR | Wilson,Br | Demoted to reserve roster | | | Before |
| 7/23/2012 | INP | Dinkelman | Signed | | | Before |
| 7/23/2012 | INP | Gillaspie | Released | | | Before |
| 7/23/2012 | INP | Gomes,B | Released | | | Before |
| 7/23/2012 | INP | LeBlanc | Signed | | | Before |
| 7/23/2012 | INP | MacDougal | Signed | | | Before |
| 7/23/2012 | INP | Paul | Released | | | Before |
| 7/23/2012 | MAI | Collmenter | Promoted to active roster | | | Before |
| 7/23/2012 | MAI | Galarraga | Demoted to reserve roster | | | Before |
| 7/23/2012 | MAI | Greinke | Promoted to active roster | | | Before |
| 7/23/2012 | MAI | Huff,D | Demoted to reserve roster | | | Before |
| 7/23/2012 | OUT | Blanks | Demoted to reserve roster | | | Before |
| 7/23/2012 | OUT | Brown,Do | Promoted to active roster | | | Before |
| 7/23/2012 | OUT | Cooper | Promoted to active roster | | | Before |
| 7/23/2012 | OUT | Drew,J | Signed | | | Before |
| 7/23/2012 | OUT | Herrera,J | Released | | | Before |
| 7/23/2012 | OUT | Herrera,J | Signed | | | Before |
| 7/23/2012 | OUT | Herrera,J | Demoted to reserve roster | | | Before |
| 7/23/2012 | PEA | Cunningham | Demoted to reserve roster | | | Before |
| 7/23/2012 | PEA | Cunningham | Promoted to active roster | | | Before |
| 7/23/2012 | PEA | Patterson,E | Promoted to active roster | | | Before |
| 7/23/2012 | PEA | Victorino | Demoted to reserve roster | | | Before |
| 7/23/2012 | PHO | Fuentes | Released | | | Before |
| 7/23/2012 | PHO | Keppinger | Promoted to active roster | | | Before |
| 7/23/2012 | PHO | Posada | Demoted to reserve roster | | | Before |
| 7/23/2012 | PHO | Powell | Signed | | | Before |
| 7/23/2012 | PIN | Ankiel | Promoted to active roster | | | Before |
| 7/23/2012 | PIN | Cassevah | Promoted to active roster | | | Before |
| 7/23/2012 | PIN | Murphy,Dan | Demoted to reserve roster | | | Before |
| 7/23/2012 | PIN | Paulino,F | Demoted to reserve roster | | | Before |
| 7/23/2012 | PIN | Reddick | Demoted to reserve roster | | | Before |
| 7/23/2012 | PIN | Sanchez,F | Promoted to active roster | | | Before |
| 7/23/2012 | QUI | Bell,J | Demoted to reserve roster | | | Before |
| 7/23/2012 | QUI | Britton | Promoted to active roster | | | Before |
| 7/23/2012 | QUI | Crawford,B | Promoted to active roster | | | Before |
| 7/23/2012 | QUI | Duffy | Demoted to reserve roster | | | Before |
| 7/23/2012 | QUI | Gamel | Promoted to active roster | | | Before |
| 7/23/2012 | QUI | Lombardozzi | Demoted to reserve roster | | | Before |
| 7/23/2012 | QUI | Montero,J | Demoted to reserve roster | | | Before |
| 7/23/2012 | QUI | Phelps | Promoted to active roster | | | Before |
| 7/23/2012 | QUI | Pie | Demoted to reserve roster | | | Before |
| 7/23/2012 | QUI | Wells,C | Promoted to active roster | | | Before |
| 7/23/2012 | SCO | Castro,R | Released | | | Before |
| 7/23/2012 | SCO | Drew,S | Demoted to reserve roster | | | Before |
| 7/23/2012 | SCO | Guzman | Promoted to active roster | | | Before |
| 7/23/2012 | SCO | Sizemore,G | Demoted to reserve roster | | | Before |
| 7/23/2012 | SCO | Snyder,C | Promoted to active roster | | | Before |
| 7/23/2012 | SCO | Valdez,W | Signed | | | Before |
| 7/23/2012 | SKT | Badenhop | Promoted to active roster | | | Before |
| 7/23/2012 | SKT | Beato | Demoted to reserve roster | | | Before |
| 7/23/2012 | SKT | Schwinden | Signed | | | Before |
| 7/23/2012 | SLG | Beckett | Demoted to reserve roster | | | Before |
| 7/23/2012 | SLG | Boggs,M | Promoted to active roster | | | Before |
| 7/23/2012 | SLG | Brignac | Promoted to active roster | | | Before |
| 7/23/2012 | SLG | Cruz,T | Promoted to active roster | | | Before |
| 7/23/2012 | SLG | Hayes | Demoted to reserve roster | | | Before |
| 7/23/2012 | SLG | Ibanez | Promoted to active roster | | | Before |
| 7/23/2012 | SLG | Lindstrom | Promoted to active roster | | | Before |
| 7/23/2012 | SLG | Lynn | Promoted to active roster | | | Before |
| 7/23/2012 | SLG | Madson | Demoted to reserve roster | | | Before |
| 7/23/2012 | SLG | Mayberry | Demoted to reserve roster | | | Before |
| 7/23/2012 | SLG | Salas | Demoted to reserve roster | | | Before |
| 7/23/2012 | SLG | Scutaro | Demoted to reserve roster | | | Before |
| 7/23/2012 | SYN | Bowden | Promoted to active roster | | | Before |
| 7/23/2012 | SYN | Carreno | Promoted to active roster | | | Before |
| 7/23/2012 | SYN | Minor | Promoted to active roster | | | Before |
| 7/23/2012 | SYN | Rivera,Ma | Demoted to reserve roster | | | Before |
| 7/23/2012 | SYN | Uehara | Demoted to reserve roster | | | Before |
| 7/23/2012 | SYN | Walden | Demoted to reserve roster | | | Before |
| 7/28/2012 | EMP | Millwood | Released | | | Before |
| 7/28/2012 | EMP | Simon | Signed | | | Before |
| 7/28/2012 | EMP | Simon | Demoted to reserve roster | | | Before |
| 7/28/2012 | EMP | Tekotte | Released | | | Before |
| 7/28/2012 | EMP | Towles | Signed | | | Before |
| 7/28/2012 | REB | Alvarez,P | Demoted to reserve roster | | | Before |
| 7/28/2012 | REB | Ellis,A | Promoted to active roster | | | Before |
| 7/28/2012 | REB | Grilli | Promoted to active roster | | | Before |
| 7/28/2012 | REB | Wilhelmsen | Demoted to reserve roster | | | Before |
| 7/28/2012 | RLF | Bergesen | Demoted to reserve roster | | | Before |
| 7/28/2012 | RLF | Choo | Promoted to active roster | | | Before |
| 7/28/2012 | RLF | Karstens | Promoted to active roster | | | Before |
| 7/28/2012 | RLF | Niese | Promoted to active roster | | | Before |
| 7/28/2012 | RLF | Sappelt | Demoted to reserve roster | | | Before |
| 7/28/2012 | RLF | Teheran | Demoted to reserve roster | | | Before |
| 7/28/2012 | SLG | Kelley | Released | | | Before |
| 7/28/2012 | SLG | Mendoza | Signed | | | Before |
| 7/28/2012 | SYN | Bowden | Released | | | Before |
| 7/28/2012 | SYN | Hamburger | Signed | | | Before |
| 7/29/2012 | B C | Borbon | Promoted to active roster | | | Before |
| 7/29/2012 | B C | Gomez,C | Demoted to reserve roster | | | Before |
| 7/29/2012 | B C | Hochevar | Promoted to active roster | | | Before |
| 7/29/2012 | B C | Oswalt | Demoted to reserve roster | | | Before |
| 7/29/2012 | B C | Sogard | Demoted to reserve roster | | | Before |
| 7/29/2012 | B C | Sweeney | Promoted to active roster | | | Before |
| 7/29/2012 | COM | Maier | Demoted to reserve roster | | | Before |
| 7/29/2012 | COM | Martinez,F | Promoted to active roster | | | Before |
| 7/29/2012 | DRI | Bastardo | Demoted to reserve roster | | | Before |
| 7/29/2012 | DRI | Bastardo | Promoted to active roster | | | Before |
| 7/29/2012 | DRI | LaHair | Demoted to reserve roster | | | Before |
| 7/29/2012 | DRI | Lester | Demoted to reserve roster | | | Before |
| 7/29/2012 | DRI | Nathan | Promoted to active roster | | | Before |
| 7/29/2012 | DRI | Nicasio | Promoted to active roster | | | Before |
| 7/29/2012 | DRI | Perez,S | Demoted to reserve roster | | | Before |
| 7/29/2012 | DRI | Saltalamacchia | Promoted to active roster | | | Before |
| 7/29/2012 | FOR | Gomez,J | Promoted to active roster | | | Before |
| 7/29/2012 | FOR | Marquis | Demoted to reserve roster | | | Before |
| 7/29/2012 | FOR | Seager | Promoted to active roster | | | Before |
| 7/29/2012 | FOR | Wallace | Demoted to reserve roster | | | Before |
| 7/29/2012 | HSX | Burnett,AJ | Demoted to reserve roster | | | Before |
| 7/29/2012 | HSX | Cordero | Demoted to reserve roster | | | Before |
| 7/29/2012 | HSX | Farnsworth | Promoted to active roster | | | Before |
| 7/29/2012 | HSX | Gee | Promoted to active roster | | | Before |
| 7/29/2012 | INP | Getz | Demoted to reserve roster | | | Before |
| 7/29/2012 | INP | Schafer,L | Demoted to reserve roster | | | Before |
| 7/29/2012 | IRI | McDonald,Ja | Demoted to reserve roster | | | Before |
| 7/29/2012 | IRI | Perez,C | Demoted to reserve roster | | | Before |
| 7/29/2012 | IRI | Shaw | Promoted to active roster | | | Before |
| 7/29/2012 | IRI | Young,CR | Promoted to active roster | | | Before |
| 7/29/2012 | MAI | Altuve | Demoted to reserve roster | | | Before |
| 7/29/2012 | MAI | Andino | Demoted to reserve roster | | | Before |
| 7/29/2012 | MAI | Collmenter | Demoted to reserve roster | | | Before |
| 7/29/2012 | MAI | Donald | Promoted to active roster | | | Before |
| 7/29/2012 | MAI | Galarraga | Promoted to active roster | | | Before |
| 7/29/2012 | MAI | Greinke | Demoted to reserve roster | | | Before |
| 7/29/2012 | MAI | Maholm | Promoted to active roster | | | Before |
| 7/29/2012 | MAI | McGehee | Promoted to active roster | | | Before |
| 7/29/2012 | MAI | Wood,Tr | Demoted to reserve roster | | | Before |
| 7/29/2012 | MAI | Wood,Tr | Promoted to active roster | | | Before |
| 7/29/2012 | OUT | Herrera,J | Released | | | Before |
| 7/29/2012 | OUT | McGee | Demoted to reserve roster | | | Before |
| 7/29/2012 | PEA | Alvarez,H | Promoted to active roster | | | Before |
| 7/29/2012 | PEA | Arrieta | Promoted to active roster | | | Before |
| 7/29/2012 | PEA | Batista | Demoted to reserve roster | | | Before |
| 7/29/2012 | PEA | Carrera | Demoted to reserve roster | | | Before |
| 7/29/2012 | PEA | Cunningham | Promoted to active roster | | | Before |
| 7/29/2012 | PEA | Halladay | Demoted to reserve roster | | | Before |
| 7/29/2012 | PEA | Halladay | Promoted to active roster | | | Before |
| 7/29/2012 | PEA | Laird,B | Promoted to active roster | | | Before |
| 7/29/2012 | PEA | Patterson,E | Demoted to reserve roster | | | Before |
| 7/29/2012 | PEA | Pineiro | Demoted to reserve roster | | | Before |
| 7/29/2012 | PHO | Napoli | Demoted to reserve roster | | | Before |
| 7/29/2012 | PIN | Carroll,J | Demoted to reserve roster | | | Before |
| 7/29/2012 | PIN | Murphy,Dan | Promoted to active roster | | | Before |
| 7/29/2012 | PIN | Schierholtz | Demoted to reserve roster | | | Before |
| 7/29/2012 | PIN | Treanor | Promoted to active roster | | | Before |
| 7/29/2012 | PIN | Weiland | Promoted to active roster | | | Before |
| 7/29/2012 | PIN | Wilson,Bo | Demoted to reserve roster | | | Before |
| 7/29/2012 | QUI | Ackley | Promoted to active roster | | | Before |
| 7/29/2012 | QUI | Gamel | Demoted to reserve roster | | | Before |
| 7/29/2012 | QUI | Martinez,J | Promoted to active roster | | | Before |
| 7/29/2012 | QUI | Phelps | Demoted to reserve roster | | | Before |
| 7/29/2012 | REB | Ellis,A | Demoted to reserve roster | | | Before |
| 7/29/2012 | REB | LaRoche,An | Signed | | | Before |
| 7/29/2012 | REB | Oliver,A | Released | | | Before |
| 7/29/2012 | SCO | Bernadina | Demoted to reserve roster | | | Before |
| 7/29/2012 | SCO | Billingsley | Demoted to reserve roster | | | Before |
| 7/29/2012 | SCO | McCarthy | Promoted to active roster | | | Before |
| 7/29/2012 | SCO | Ross,D | Promoted to active roster | | | Before |
| 7/29/2012 | SCO | Snyder,C | Demoted to reserve roster | | | Before |
| 7/29/2012 | SCO | Taylor | Promoted to active roster | | | Before |
| 7/29/2012 | SKT | Damon | Promoted to active roster | | | Before |
| 7/29/2012 | SKT | Moreland | Demoted to reserve roster | | | Before |
| 7/29/2012 | SKT | Overbay | Promoted to active roster | | | Before |
| 7/29/2012 | SKT | Schwinden | Demoted to reserve roster | | | Before |
| 7/29/2012 | SKT | Span | Demoted to reserve roster | | | Before |
| 7/29/2012 | SLG | Beckett | Promoted to active roster | | | Before |
| 7/29/2012 | SLG | Boggs,M | Demoted to reserve roster | | | Before |
| 7/29/2012 | SLG | Brignac | Demoted to reserve roster | | | Before |
| 7/29/2012 | SLG | Cruz,T | Demoted to reserve roster | | | Before |
| 7/29/2012 | SLG | Eveland | Demoted to reserve roster | | | Before |
| 7/29/2012 | SLG | Hayes | Promoted to active roster | | | Before |
| 7/29/2012 | SLG | Ibanez | Demoted to reserve roster | | | Before |
| 7/29/2012 | SLG | Lindstrom | Demoted to reserve roster | | | Before |
| 7/29/2012 | SLG | Lynn | Demoted to reserve roster | | | Before |
| 7/29/2012 | SLG | Madson | Promoted to active roster | | | Before |
| 7/29/2012 | SLG | Mayberry | Promoted to active roster | | | Before |
| 7/29/2012 | SLG | Mendoza | Demoted to reserve roster | | | Before |
| 7/29/2012 | SLG | Salas | Promoted to active roster | | | Before |
| 7/29/2012 | SLG | Scutaro | Promoted to active roster | | | Before |
| 7/29/2012 | SLG | Vogelsong | Promoted to active roster | | | Before |
| 8/2/2012 | EMP | Milone | Demoted to reserve roster | | | Before |
| 8/2/2012 | EMP | Simon | Promoted to active roster | | | Before |
| 8/3/2012 | B C | Floyd | Promoted to active roster | | | Before |
| 8/3/2012 | B C | Furbush | Demoted to reserve roster | | | Before |
| 8/3/2012 | B C | Lueke | Demoted to reserve roster | | | Before |
| 8/3/2012 | B C | Oswalt | Promoted to active roster | | | Before |
| 8/3/2012 | REB | Carmona | Demoted to reserve roster | | | Before |
| 8/3/2012 | REB | Ellis,A | Promoted to active roster | | | Before |
| 8/3/2012 | REB | Hairston,S | Demoted to reserve roster | | | Before |
| 8/3/2012 | REB | LaRoche,An | Signed | | | Before |
| 8/3/2012 | REB | Oliver,A | Released | | | Before |
| 8/3/2012 | REB | Peavy | Promoted to active roster | | | Before |
| 8/3/2012 | SID | Davis,W | Demoted to reserve roster | | | Before |
| 8/3/2012 | SID | Detwiler | Promoted to active roster | | | Before |
| 8/4/2012 | BOU | Constanza | Signed | | | Before |
| 8/4/2012 | BOU | Cowgill | Released | | | Before |
| 8/4/2012 | BOU | Escalona,E | Released | | | Before |
| 8/4/2012 | BOU | Isringhausen | Signed | | | Before |
| 8/4/2012 | COM | Beltre | Demoted to reserve roster | | | Before |
| 8/4/2012 | COM | Forsythe | Promoted to active roster | | | Before |
| 8/4/2012 | FOR | Davis,B | Signed | | | Before |
| 8/4/2012 | FOR | Gomez,J | Demoted to reserve roster | | | Before |
| 8/4/2012 | FOR | Hinske | Released | | | Before |
| 8/4/2012 | FOR | Marquis | Promoted to active roster | | | Before |
| 8/4/2012 | FOR | Morton | Demoted to reserve roster | | | Before |
| 8/4/2012 | FOR | Paredes | Demoted to reserve roster | | | Before |
| 8/4/2012 | FOR | Richard | Promoted to active roster | | | Before |
| 8/4/2012 | FOR | Wallace | Promoted to active roster | | | Before |
| 8/4/2012 | MAI | Galarraga | Released | | | Before |
| 8/4/2012 | MAI | Huff,D | Released | | | Before |
| 8/4/2012 | MAI | Teaford | Signed | | | Before |
| 8/4/2012 | MAI | Tejada,M | Signed | | | Before |
| 8/4/2012 | PHO | Abreu,B | Promoted to active roster | | | Before |
| 8/4/2012 | PHO | Baker,Je | Demoted to reserve roster | | | Before |
| 8/4/2012 | PHO | Colon | Promoted to active roster | | | Before |
| 8/4/2012 | PHO | Humber | Demoted to reserve roster | | | Before |
| 8/4/2012 | PHO | Kubel | Demoted to reserve roster | | | Before |
| 8/4/2012 | PHO | Ludwick | Promoted to active roster | | | Before |
| 8/4/2012 | PHO | Navarro,D | Released | | | Before |
| 8/4/2012 | PHO | Posada | Demoted to reserve roster | | | Before |
| 8/4/2012 | PHO | Posada | Promoted to active roster | | | Before |
| 8/4/2012 | PHO | Schneider | Signed | | | Before |
| 8/4/2012 | PIN | Sanchez,F | Demoted to reserve roster | | | Before |
| 8/4/2012 | PIN | Schierholtz | Promoted to active roster | | | Before |
| 8/4/2012 | RLF | Headley | Demoted to reserve roster | | | Before |
| 8/4/2012 | RLF | Stewart,I | Promoted to active roster | | | Before |
| 8/4/2012 | SCO | Billingsley | Promoted to active roster | | | Before |
| 8/4/2012 | SCO | Helton | Promoted to active roster | | | Before |
| 8/4/2012 | SCO | Lannan | Demoted to reserve roster | | | Before |
| 8/4/2012 | SCO | Parmelee | Demoted to reserve roster | | | Before |
| 8/4/2012 | SLG | Beckett | Demoted to reserve roster | | | Before |
| 8/4/2012 | SLG | Boggs,M | Promoted to active roster | | | Before |
| 8/4/2012 | SLG | Eveland | Released | | | Before |
| 8/4/2012 | SLG | Eveland | Promoted to active roster | | | Before |
| 8/4/2012 | SLG | Huff,D | Signed | | | Before |
| 8/4/2012 | SLG | Huff,D | Demoted to reserve roster | | | Before |
| 8/4/2012 | SLG | Ibanez | Promoted to active roster | | | Before |
| 8/4/2012 | SLG | Jurrjens | Demoted to reserve roster | | | Before |
| 8/4/2012 | SLG | Presley | Demoted to reserve roster | | | Before |
| 8/4/2012 | SYN | Bailey,H | Demoted to reserve roster | | | Before |
| 8/4/2012 | SYN | Carreno | Demoted to reserve roster | | | Before |
| 8/4/2012 | SYN | Hamburger | Demoted to reserve roster | | | Before |
| 8/4/2012 | SYN | Rivera,Ma | Promoted to active roster | | | Before |
| 8/4/2012 | SYN | Uehara | Promoted to active roster | | | Before |
| 8/4/2012 | SYN | Walden | Promoted to active roster | | | Before |
| 8/7/2012 | MAI | Tejada,M | Signed | | | Before |
| 8/8/2012 | OUT | Blanks | Demoted to reserve roster | | | Before |
| 8/8/2012 | OUT | Brown,Do | Promoted to active roster | | | Before |
| 8/8/2012 | OUT | Cleto | Promoted to active roster | | | Before |
| 8/8/2012 | SLG | Beckett | Promoted to active roster | | | Before |
| 8/8/2012 | SLG | Brignac | Promoted to active roster | | | Before |
| 8/8/2012 | SLG | Cruz,T | Promoted to active roster | | | Before |
| 8/8/2012 | SLG | Eveland | Demoted to reserve roster | | | Before |
| 8/8/2012 | SLG | Hayes | Demoted to reserve roster | | | Before |
| 8/8/2012 | SLG | Scutaro | Demoted to reserve roster | | | Before |
| 8/9/2012 | COM | Beltre | Promoted to active roster | | | Before |
| 8/9/2012 | COM | Forsythe | Demoted to reserve roster | | | Before |
| 8/9/2012 | COM | Martinez,F | Demoted to reserve roster | | | Before |
| 8/9/2012 | COM | Strop | Promoted to active roster | | | Before |
| 8/9/2012 | REB | Bray | Demoted to reserve roster | | | Before |
| 8/9/2012 | REB | Crow | Demoted to reserve roster | | | Before |
| 8/9/2012 | REB | Ellis,A | Demoted to reserve roster | | | Before |
| 8/9/2012 | REB | Hairston,S | Promoted to active roster | | | Before |
| 8/9/2012 | REB | Soriano,R | Promoted to active roster | | | Before |
| 8/9/2012 | REB | Wilhelmsen | Promoted to active roster | | | Before |
| 8/10/2012 | EAG | Brantley | Promoted to active roster | | | Before |
| 8/10/2012 | EAG | Capps | Promoted to active roster | | | Before |
| 8/10/2012 | EAG | Cruz,N | Demoted to reserve roster | | | Before |
| 8/10/2012 | EAG | Gregg | Demoted to reserve roster | | | Before |
| 8/10/2012 | FOR | Cobb | Demoted to reserve roster | | | Before |
| 8/10/2012 | FOR | Gomez,J | Promoted to active roster | | | Before |
| 8/10/2012 | FOR | Morton | Promoted to active roster | | | Before |
| 8/10/2012 | FOR | Nova | Demoted to reserve roster | | | Before |
| 8/10/2012 | FOR | Samardzija | Demoted to reserve roster | | | Before |
| 8/10/2012 | FOR | Wilson,Br | Promoted to active roster | | | Before |
| 8/10/2012 | HSX | Brothers | Demoted to reserve roster | | | Before |
| 8/10/2012 | HSX | Burnett,AJ | Promoted to active roster | | | Before |
| 8/10/2012 | HSX | Cordero | Promoted to active roster | | | Before |
| 8/10/2012 | HSX | Putz | Demoted to reserve roster | | | Before |
| 8/10/2012 | INP | Kotsay | Promoted to active roster | | | Before |
| 8/10/2012 | INP | Street | Demoted to reserve roster | | | Before |
| 8/10/2012 | IRI | Cairo | Demoted to reserve roster | | | Before |
| 8/10/2012 | IRI | Cairo | Promoted to active roster | | | Before |
| 8/10/2012 | IRI | Crain | Demoted to reserve roster | | | Before |
| 8/10/2012 | IRI | Frasor | Promoted to active roster | | | Before |
| 8/10/2012 | IRI | McDonald,Ja | Promoted to active roster | | | Before |
| 8/10/2012 | IRI | Schumaker | Promoted to active roster | | | Before |
| 8/10/2012 | IRI | Utley | Demoted to reserve roster | | | Before |
| 8/10/2012 | IRI | Young,CR | Demoted to reserve roster | | | Before |
| 8/10/2012 | MAI | Alburquerque | Promoted to active roster | | | Before |
| 8/10/2012 | MAI | Collmenter | Demoted to reserve roster | | | Before |
| 8/10/2012 | MAI | Downs,S | Promoted to active roster | | | Before |
| 8/10/2012 | MAI | Holland,G | Demoted to reserve roster | | | Before |
| 8/10/2012 | MAI | Maholm | Promoted to active roster | | | Before |
| 8/10/2012 | MAI | Sanchez,E | Demoted to reserve roster | | | Before |
| 8/10/2012 | OUT | Cabrera,O | Signed | | | Before |
| 8/10/2012 | OUT | Elbert | Promoted to active roster | | | Before |
| 8/10/2012 | OUT | Rizzo | Demoted to reserve roster | | | Before |
| 8/10/2012 | OUT | Wells,R | Released | | | Before |
| 8/10/2012 | PEA | Bass | Released | | | Before |
| 8/10/2012 | PEA | Batista | Released | | | Before |
| 8/10/2012 | PEA | Fuentes | Signed | | | Before |
| 8/10/2012 | PEA | Lidge | Released | | | Before |
| 8/10/2012 | PEA | Owings | Signed | | | Before |
| 8/10/2012 | PEA | Pineiro | Promoted to active roster | | | Before |
| 8/10/2012 | PEA | Qualls | Demoted to reserve roster | | | Before |
| 8/10/2012 | PEA | Sanches | Signed | | | Before |
| 8/10/2012 | PEA | Tillman | Demoted to reserve roster | | | Before |
| 8/10/2012 | PEA | Vazquez | Demoted to reserve roster | | | Before |
| 8/10/2012 | PHO | Baker,Je | Promoted to active roster | | | Before |
| 8/10/2012 | PHO | Colon | Demoted to reserve roster | | | Before |
| 8/10/2012 | PHO | Duncan | Demoted to reserve roster | | | Before |
| 8/10/2012 | PHO | Humber | Promoted to active roster | | | Before |
| 8/10/2012 | PHO | Johnson,C | Promoted to active roster | | | Before |
| 8/10/2012 | PHO | Napoli | Promoted to active roster | | | Before |
| 8/10/2012 | PHO | Powell | Demoted to reserve roster | | | Before |
| 8/10/2012 | PHO | Roberts,R | Demoted to reserve roster | | | Before |
| 8/10/2012 | PIN | Davis,I | Promoted to active roster | | | Before |
| 8/10/2012 | PIN | Davis,R | Demoted to reserve roster | | | Before |
| 8/10/2012 | PIN | Moseley | Demoted to reserve roster | | | Before |
| 8/10/2012 | PIN | Paulino,F | Promoted to active roster | | | Before |
| 8/10/2012 | PIN | Reddick | Promoted to active roster | | | Before |
| 8/10/2012 | PIN | Schierholtz | Demoted to reserve roster | | | Before |
| 8/10/2012 | QUI | Ackley | Demoted to reserve roster | | | Before |
| 8/10/2012 | QUI | Crawford,B | Demoted to reserve roster | | | Before |
| 8/10/2012 | QUI | Gamel | Promoted to active roster | | | Before |
| 8/10/2012 | QUI | Martinez,J | Demoted to reserve roster | | | Before |
| 8/10/2012 | QUI | Phelps | Promoted to active roster | | | Before |
| 8/10/2012 | QUI | Pie | Promoted to active roster | | | Before |
| 8/10/2012 | RLF | Bergesen | Promoted to active roster | | | Before |
| 8/10/2012 | RLF | Jenks | Demoted to reserve roster | | | Before |
| 8/10/2012 | SCO | Bernadina | Promoted to active roster | | | Before |
| 8/10/2012 | SCO | Carrasco,C | Demoted to reserve roster | | | Before |
| 8/10/2012 | SCO | Drew,S | Promoted to active roster | | | Before |
| 8/10/2012 | SCO | Lannan | Promoted to active roster | | | Before |
| 8/10/2012 | SCO | Morse | Demoted to reserve roster | | | Before |
| 8/10/2012 | SCO | Phillips,B | Demoted to reserve roster | | | Before |
| 8/10/2012 | SKT | Blackburn | Demoted to reserve roster | | | Before |
| 8/10/2012 | SKT | Feldman | Promoted to active roster | | | Before |
| 8/10/2012 | SKT | Gonzalez,M | Demoted to reserve roster | | | Before |
| 8/10/2012 | SKT | Moreland | Promoted to active roster | | | Before |
| 8/10/2012 | SKT | Overbay | Demoted to reserve roster | | | Before |
| 8/10/2012 | SKT | Schwinden | Promoted to active roster | | | Before |
| 8/10/2012 | SLG | Eveland | Released | | | Before |
| 8/10/2012 | SLG | Huff,D | Signed | | | Before |
| 8/10/2012 | SYN | Bailey,H | Promoted to active roster | | | Before |
| 8/10/2012 | SYN | Beachy | Demoted to reserve roster | | | Before |
| 8/14/2012 | REB | Bedard | Demoted to reserve roster | | | Before |
| 8/14/2012 | REB | Bray | Promoted to active roster | | | Before |
| 8/14/2012 | REB | Johnson,Jo | Promoted to active roster | | | Before |
| 8/14/2012 | REB | Wilhelmsen | Demoted to reserve roster | | | Before |
| 8/15/2012 | DRI | Barton | Released | | | Before |
| 8/15/2012 | DRI | Devine | Signed | | | Before |
| 8/15/2012 | DRI | Giavotella | Promoted to active roster | | | Before |
| 8/15/2012 | DRI | LaHair | Demoted to reserve roster | | | Before |
| 8/15/2012 | EAG | Alfonzo | Signed | | | Before |
| 8/15/2012 | EAG | Coleman,L | Promoted to active roster | | | Before |
| 8/15/2012 | EAG | Pacheco | Promoted to active roster | | | Before |
| 8/15/2012 | EAG | Pauley | Released | | | Before |
| 8/15/2012 | EAG | Stutes | Demoted to reserve roster | | | Before |
| 8/15/2012 | EAG | Zimmerman | Demoted to reserve roster | | | Before |
| 8/15/2012 | EMP | Dillard | Signed | | | Before |
| 8/15/2012 | EMP | Gimenez,C | Signed | | | Before |
| 8/15/2012 | EMP | Jimenez,C | Released | | | Before |
| 8/15/2012 | EMP | Jimenez,C | Signed | | | Before |
| 8/15/2012 | EMP | Jimenez,C | Demoted to reserve roster | | | Before |
| 8/15/2012 | EMP | Kouzmanoff | Signed | | | Before |
| 8/15/2012 | EMP | Rolen | Released | | | Before |
| 8/15/2012 | EMP | Slowey | Released | | | Before |
| 8/15/2012 | EMP | Towles | Released | | | Before |
| 8/15/2012 | FOR | Gomez,J | Demoted to reserve roster | | | Before |
| 8/15/2012 | FOR | Nova | Promoted to active roster | | | Before |
| 8/15/2012 | HSX | Colvin | Demoted to reserve roster | | | Before |
| 8/15/2012 | HSX | de Aza | Promoted to active roster | | | Before |
| 8/15/2012 | LEG | Boesch | Demoted to reserve roster | | | Before |
| 8/15/2012 | LEG | Boesch | Promoted to active roster | | | Before |
| 8/15/2012 | LEG | Broxton | Promoted to active roster | | | Before |
| 8/15/2012 | LEG | Carp | Demoted to reserve roster | | | Before |
| 8/15/2012 | LEG | Carp | Promoted to active roster | | | Before |
| 8/15/2012 | LEG | Carter | Promoted to active roster | | | Before |
| 8/15/2012 | LEG | Cervelli | Demoted to reserve roster | | | Before |
| 8/15/2012 | LEG | Cishek | Promoted to active roster | | | Before |
| 8/15/2012 | LEG | Cueto | Demoted to reserve roster | | | Before |
| 8/15/2012 | LEG | Downs,M | Demoted to reserve roster | | | Before |
| 8/15/2012 | LEG | Gutierrez,J | Demoted to reserve roster | | | Before |
| 8/15/2012 | LEG | Jennings | Promoted to active roster | | | Before |
| 8/15/2012 | LEG | Sanchez,J | Promoted to active roster | | | Before |
| 8/15/2012 | LEG | Sipp | Demoted to reserve roster | | | Before |
| 8/15/2012 | LEG | Spence | Promoted to active roster | | | Before |
| 8/15/2012 | LEG | Takahashi | Demoted to reserve roster | | | Before |
| 8/15/2012 | MAI | Altuve | Promoted to active roster | | | Before |
| 8/15/2012 | MAI | Andino | Promoted to active roster | | | Before |
| 8/15/2012 | MAI | Collmenter | Promoted to active roster | | | Before |
| 8/15/2012 | MAI | Donald | Promoted to active roster | | | Before |
| 8/15/2012 | MAI | Greinke | Promoted to active roster | | | Before |
| 8/15/2012 | MAI | Harrison,J | Demoted to reserve roster | | | Before |
| 8/15/2012 | MAI | Hart | Demoted to reserve roster | | | Before |
| 8/15/2012 | MAI | McGehee | Demoted to reserve roster | | | Before |
| 8/15/2012 | MAI | Stewart,C | Demoted to reserve roster | | | Before |
| 8/15/2012 | MAI | Wood,Tr | Demoted to reserve roster | | | Before |
| 8/15/2012 | OUT | Cleto | Demoted to reserve roster | | | Before |
| 8/15/2012 | OUT | Conger | Promoted to active roster | | | Before |
| 8/15/2012 | OUT | De Los Santos | Promoted to active roster | | | Before |
| 8/15/2012 | OUT | Elbert | Demoted to reserve roster | | | Before |
| 8/15/2012 | OUT | Encarnacion | Demoted to reserve roster | | | Before |
| 8/15/2012 | OUT | Hanson | Demoted to reserve roster | | | Before |
| 8/15/2012 | OUT | White | Demoted to reserve roster | | | Before |
| 8/15/2012 | OUT | White | Promoted to active roster | | | Before |
| 8/15/2012 | PEA | Laird,B | Demoted to reserve roster | | | Before |
| 8/15/2012 | PEA | LeMahieu | Demoted to reserve roster | | | Before |
| 8/15/2012 | PEA | Patterson,E | Promoted to active roster | | | Before |
| 8/15/2012 | PEA | Pineiro | Demoted to reserve roster | | | Before |
| 8/15/2012 | PEA | Vazquez | Promoted to active roster | | | Before |
| 8/15/2012 | PEA | Victorino | Promoted to active roster | | | Before |
| 8/15/2012 | PHO | Baker,Je | Demoted to reserve roster | | | Before |
| 8/15/2012 | PHO | Duncan | Promoted to active roster | | | Before |
| 8/15/2012 | PHO | Gomes,J | Demoted to reserve roster | | | Before |
| 8/15/2012 | PHO | Loe | Promoted to active roster | | | Before |
| 8/15/2012 | PIN | Carroll,J | Promoted to active roster | | | Before |
| 8/15/2012 | PIN | Coleman,C | Promoted to active roster | | | Before |
| 8/15/2012 | PIN | Reddick | Demoted to reserve roster | | | Before |
| 8/15/2012 | PIN | Schierholtz | Promoted to active roster | | | Before |
| 8/15/2012 | PIN | Weiland | Demoted to reserve roster | | | Before |
| 8/15/2012 | PIN | Youkilis | Demoted to reserve roster | | | Before |
| 8/15/2012 | QUI | Bell,J | Promoted to active roster | | | Before |
| 8/15/2012 | QUI | Crawford,B | Promoted to active roster | | | Before |
| 8/15/2012 | QUI | Duffy | Promoted to active roster | | | Before |
| 8/15/2012 | QUI | Gamel | Demoted to reserve roster | | | Before |
| 8/15/2012 | QUI | Garcia,F | Demoted to reserve roster | | | Before |
| 8/15/2012 | QUI | Harden | Promoted to active roster | | | Before |
| 8/15/2012 | QUI | Lyles | Demoted to reserve roster | | | Before |
| 8/15/2012 | QUI | Phelps | Demoted to reserve roster | | | Before |
| 8/15/2012 | RLF | Gutierrez,F | Promoted to active roster | | | Before |
| 8/15/2012 | RLF | Tosoni | Demoted to reserve roster | | | Before |
| 8/15/2012 | SCO | Helton | Demoted to reserve roster | | | Before |
| 8/15/2012 | SCO | Morse | Promoted to active roster | | | Before |
| 8/15/2012 | SCO | Parmelee | Promoted to active roster | | | Before |
| 8/15/2012 | SCO | Phillips,B | Promoted to active roster | | | Before |
| 8/15/2012 | SCO | Plouffe | Demoted to reserve roster | | | Before |
| 8/15/2012 | SCO | Ross,D | Demoted to reserve roster | | | Before |
| 8/15/2012 | SCO | Snyder,C | Promoted to active roster | | | Before |
| 8/15/2012 | SCO | Taylor | Demoted to reserve roster | | | Before |
| 8/15/2012 | SKT | Hernandez,L | Demoted to reserve roster | | | Before |
| 8/15/2012 | SKT | Matsuzaka | Promoted to active roster | | | Before |
| 8/15/2012 | SLG | Boggs,M | Demoted to reserve roster | | | Before |
| 8/15/2012 | SLG | Brignac | Demoted to reserve roster | | | Before |
| 8/15/2012 | SLG | Gorzelanny | Demoted to reserve roster | | | Before |
| 8/15/2012 | SLG | Jurrjens | Promoted to active roster | | | Before |
| 8/15/2012 | SLG | Lindstrom | Promoted to active roster | | | Before |
| 8/15/2012 | SLG | Scutaro | Promoted to active roster | | | Before |
| 8/15/2012 | SYN | Lindblom | Promoted to active roster | | | Before |
| 8/15/2012 | SYN | Thompson,R | Demoted to reserve roster | | | Before |
| 8/16/2012 | SID | Davis,C | Promoted to active roster | | | Before |
| 8/16/2012 | SID | Kotchman | Demoted to reserve roster | | | Before |
| 8/21/2012 | EMP | Gimenez,C | Signed | | | Before |
| 8/21/2012 | EMP | Jimenez,C | Released | | | Before |
| 8/21/2012 | REB | Alvarez,P | Promoted to active roster | | | Before |
| 8/21/2012 | REB | Bedard | Promoted to active roster | | | Before |
| 8/21/2012 | REB | Benson | Promoted to active roster | | | Before |
| 8/21/2012 | REB | Carmona | Promoted to active roster | | | Before |
| 8/21/2012 | REB | Crow | Promoted to active roster | | | Before |
| 8/21/2012 | REB | Ellis,A | Promoted to active roster | | | Before |
| 8/21/2012 | REB | Martin,L | Promoted to active roster | | | Before |
| 8/21/2012 | REB | Medlen | Promoted to active roster | | | Before |
| 8/21/2012 | REB | Torres,Al | Promoted to active roster | | | Before |
| 8/21/2012 | REB | Wilhelmsen | Promoted to active roster | | | Before |
| 8/21/2012 | SKT | Adams,M | Demoted to reserve roster | | | Before |
| 8/21/2012 | SKT | Beato | Promoted to active roster | | | Before |
| 8/21/2012 | SKT | Blackburn | Promoted to active roster | | | Before |
| 8/21/2012 | SKT | Gregerson | Demoted to reserve roster | | | Before |
| 8/21/2012 | SKT | Hamilton,J | Demoted to reserve roster | | | Before |
| 8/21/2012 | SKT | Hernandez,L | Promoted to active roster | | | Before |
| 8/21/2012 | SKT | Matsuzaka | Demoted to reserve roster | | | Before |
| 8/21/2012 | SKT | Schwinden | Demoted to reserve roster | | | Before |
| 8/21/2012 | SKT | Span | Promoted to active roster | | | Before |
| 8/21/2012 | SKT | Wright,J | Promoted to active roster | | | Before |
| 8/23/2012 | B C | Borbon | Promoted to active roster | | | Before |
| 8/23/2012 | B C | Flores | Promoted to active roster | | | Before |
| 8/23/2012 | B C | Furbush | Promoted to active roster | | | Before |
| 8/23/2012 | B C | Green,T | Promoted to active roster | | | Before |
| 8/23/2012 | B C | Lueke | Promoted to active roster | | | Before |
| 8/23/2012 | B C | Matusz | Promoted to active roster | | | Before |
| 8/23/2012 | B C | Reimold | Promoted to active roster | | | Before |
| 8/23/2012 | B C | Schafer,J | Promoted to active roster | | | Before |
| 8/23/2012 | B C | Sogard | Promoted to active roster | | | Before |
| 8/23/2012 | B C | Young,E | Promoted to active roster | | | Before |
| 8/23/2012 | BOU | Chisenhall | Promoted to active roster | | | Before |
| 8/23/2012 | BOU | Correia | Demoted to reserve roster | | | Before |
| 8/23/2012 | BOU | Renteria | Demoted to reserve roster | | | Before |
| 8/23/2012 | BOU | Santiago,R | Promoted to active roster | | | Before |
| 8/23/2012 | BOU | Teagarden | Promoted to active roster | | | Before |
| 8/23/2012 | BOU | Zimmermann | Promoted to active roster | | | Before |
| 8/23/2012 | COM | Adams,R | Promoted to active roster | | | Before |
| 8/23/2012 | COM | Balester | Promoted to active roster | | | Before |
| 8/23/2012 | COM | Federowicz | Promoted to active roster | | | Before |
| 8/23/2012 | COM | Forsythe | Promoted to active roster | | | Before |
| 8/23/2012 | COM | Jeffress | Promoted to active roster | | | Before |
| 8/23/2012 | COM | Maier | Promoted to active roster | | | Before |
| 8/23/2012 | COM | Martinez,F | Promoted to active roster | | | Before |
| 8/23/2012 | COM | Nelson | Promoted to active roster | | | Before |
| 8/23/2012 | COM | Roberts,B | Promoted to active roster | | | Before |
| 8/23/2012 | DRI | Bastardo | Promoted to active roster | | | Before |
| 8/23/2012 | DRI | Blackmon | Promoted to active roster | | | Before |
| 8/23/2012 | DRI | Cabrera,E | Promoted to active roster | | | Before |
| 8/23/2012 | DRI | Devine | Promoted to active roster | | | Before |
| 8/23/2012 | DRI | Ka'aihue | Promoted to active roster | | | Before |
| 8/23/2012 | DRI | LaHair | Promoted to active roster | | | Before |
| 8/23/2012 | DRI | Nicasio | Promoted to active roster | | | Before |
| 8/23/2012 | DRI | Perez,S | Demoted to reserve roster | | | Before |
| 8/23/2012 | DRI | Perez,S | Promoted to active roster | | | Before |
| 8/23/2012 | DRI | Ramirez,Ha | Promoted to active roster | | | Before |
| 8/23/2012 | DRI | Sanchez,H | Promoted to active roster | | | Before |
| 8/23/2012 | DRI | Varitek | Promoted to active roster | | | Before |
| 8/23/2012 | EAG | Beavan | Promoted to active roster | | | Before |
| 8/23/2012 | EAG | Campana | Demoted to reserve roster | | | Before |
| 8/23/2012 | EAG | Cruz,N | Promoted to active roster | | | Before |
| 8/23/2012 | EAG | Gregg | Promoted to active roster | | | Before |
| 8/23/2012 | EAG | Janish | Promoted to active roster | | | Before |
| 8/23/2012 | EAG | Lackey | Promoted to active roster | | | Before |
| 8/23/2012 | EAG | Maldonado | Promoted to active roster | | | Before |
| 8/23/2012 | EAG | Miley | Promoted to active roster | | | Before |
| 8/23/2012 | EAG | Stutes | Promoted to active roster | | | Before |
| 8/23/2012 | EAG | Zimmerman | Promoted to active roster | | | Before |
| 8/23/2012 | EMP | Hendriks | Promoted to active roster | | | Before |
| 8/23/2012 | FOR | Chapman | Promoted to active roster | | | Before |
| 8/23/2012 | FOR | Davis,B | Released | | | Before |
| 8/23/2012 | FOR | Gomez,J | Promoted to active roster | | | Before |
| 8/23/2012 | FOR | Kendrick,K | Demoted to reserve roster | | | Before |
| 8/23/2012 | FOR | Lowe,M | Promoted to active roster | | | Before |
| 8/23/2012 | FOR | Richard | Demoted to reserve roster | | | Before |
| 8/23/2012 | FOR | Sale | Demoted to reserve roster | | | Before |
| 8/23/2012 | FOR | Sellers | Signed | | | Before |
| 8/23/2012 | FOR | Wood,Br | Demoted to reserve roster | | | Before |
| 8/23/2012 | HSX | Brothers | Promoted to active roster | | | Before |
| 8/23/2012 | HSX | Colvin | Promoted to active roster | | | Before |
| 8/23/2012 | HSX | Flowers | Promoted to active roster | | | Before |
| 8/23/2012 | HSX | Guyer | Promoted to active roster | | | Before |
| 8/23/2012 | HSX | Litsch | Promoted to active roster | | | Before |
| 8/23/2012 | HSX | Putz | Promoted to active roster | | | Before |
| 8/23/2012 | HSX | Ramirez,M | Promoted to active roster | | | Before |
| 8/23/2012 | INP | Aviles | Demoted to reserve roster | | | Before |
| 8/23/2012 | INP | Danks | Demoted to reserve roster | | | Before |
| 8/23/2012 | INP | Dobbs | Promoted to active roster | | | Before |
| 8/23/2012 | INP | Godfrey | Signed | | | Before |
| 8/23/2012 | INP | Gordon,D | Promoted to active roster | | | Before |
| 8/23/2012 | INP | Liriano | Demoted to reserve roster | | | Before |
| 8/23/2012 | INP | Nunez,E | Demoted to reserve roster | | | Before |
| 8/23/2012 | INP | Valaika | Released | | | Before |
| 8/23/2012 | IRI | Amarista | Promoted to active roster | | | Before |
| 8/23/2012 | IRI | Coghlan | Promoted to active roster | | | Before |
| 8/23/2012 | IRI | Crain | Promoted to active roster | | | Before |
| 8/23/2012 | IRI | Cruz,J | Released | | | Before |
| 8/23/2012 | IRI | Lind | Promoted to active roster | | | Before |
| 8/23/2012 | IRI | Mesoraco | Promoted to active roster | | | Before |
| 8/23/2012 | IRI | Perez,C | Promoted to active roster | | | Before |
| 8/23/2012 | IRI | Tatum | Signed | | | Before |
| 8/23/2012 | IRI | Utley | Promoted to active roster | | | Before |
| 8/23/2012 | LEG | Adcock | Promoted to active roster | | | Before |
| 8/23/2012 | LEG | Cueto | Promoted to active roster | | | Before |
| 8/23/2012 | LEG | Hand | Promoted to active roster | | | Before |
| 8/23/2012 | LEG | Sipp | Promoted to active roster | | | Before |
| 8/23/2012 | LEG | Takahashi | Promoted to active roster | | | Before |
| 8/23/2012 | LEG | Volstad | Promoted to active roster | | | Before |
| 8/23/2012 | MAI | Canzler | Demoted to reserve roster | | | Before |
| 8/23/2012 | MAI | Canzler | Promoted to active roster | | | Before |
| 8/23/2012 | MAI | Donald | Demoted to reserve roster | | | Before |
| 8/23/2012 | MAI | Gentry | Promoted to active roster | | | Before |
| 8/23/2012 | MAI | Harrison,J | Promoted to active roster | | | Before |
| 8/23/2012 | MAI | Hart | Promoted to active roster | | | Before |
| 8/23/2012 | MAI | McGehee | Promoted to active roster | | | Before |
| 8/23/2012 | MAI | Sanchez,E | Promoted to active roster | | | Before |
| 8/23/2012 | MAI | Schlereth | Promoted to active roster | | | Before |
| 8/23/2012 | MAI | Stewart,C | Promoted to active roster | | | Before |
| 8/23/2012 | MAI | Teaford | Demoted to reserve roster | | | Before |
| 8/23/2012 | MAI | Wood,Tr | Demoted to reserve roster | | | Before |
| 8/23/2012 | MAI | Wood,Tr | Promoted to active roster | | | Before |
| 8/23/2012 | OUT | Cleto | Released | | | Before |
| 8/23/2012 | OUT | De Los Santos | Released | | | Before |
| 8/23/2012 | OUT | Duke | Signed | | | Before |
| 8/23/2012 | OUT | Dunn,M | Released | | | Before |
| 8/23/2012 | OUT | Miller,A | Signed | | | Before |
| 8/23/2012 | OUT | Pridie | Signed | | | Before |
| 8/23/2012 | OUT | Rasmus | Demoted to reserve roster | | | Before |
| 8/23/2012 | OUT | White | Demoted to reserve roster | | | Before |
| 8/23/2012 | OUT | Willis | Signed | | | Before |
| 8/23/2012 | OUT | Wood,Bl | Released | | | Before |
| 8/23/2012 | PEA | Laird,B | Promoted to active roster | | | Before |
| 8/23/2012 | PEA | LeMahieu | Promoted to active roster | | | Before |
| 8/23/2012 | PEA | Morneau | Promoted to active roster | | | Before |
| 8/23/2012 | PEA | Qualls | Promoted to active roster | | | Before |
| 8/23/2012 | PEA | Romine,Au | Promoted to active roster | | | Before |
| 8/23/2012 | PEA | Tillman | Promoted to active roster | | | Before |
| 8/23/2012 | PHO | Colon | Promoted to active roster | | | Before |
| 8/23/2012 | PHO | Duncan | Promoted to active roster | | | Before |
| 8/23/2012 | PHO | Kubel | Promoted to active roster | | | Before |
| 8/23/2012 | PHO | Loe | Promoted to active roster | | | Before |
| 8/23/2012 | PHO | Posada | Promoted to active roster | | | Before |
| 8/23/2012 | PHO | Powell | Promoted to active roster | | | Before |
| 8/23/2012 | PHO | Punto | Promoted to active roster | | | Before |
| 8/23/2012 | PHO | Roberts,R | Promoted to active roster | | | Before |
| 8/23/2012 | PHO | Tazawa | Promoted to active roster | | | Before |
| 8/23/2012 | PHO | Webb | Promoted to active roster | | | Before |
| 8/23/2012 | PIN | Cain,L | Promoted to active roster | | | Before |
| 8/23/2012 | PIN | Castillo,W | Promoted to active roster | | | Before |
| 8/23/2012 | PIN | Davis,R | Promoted to active roster | | | Before |
| 8/23/2012 | PIN | Iglesias | Promoted to active roster | | | Before |
| 8/23/2012 | PIN | Moseley | Promoted to active roster | | | Before |
| 8/23/2012 | PIN | Reddick | Promoted to active roster | | | Before |
| 8/23/2012 | PIN | Sanchez,F | Promoted to active roster | | | Before |
| 8/23/2012 | PIN | Weiland | Promoted to active roster | | | Before |
| 8/23/2012 | PIN | Youkilis | Promoted to active roster | | | Before |
| 8/23/2012 | QUI | Ackley | Promoted to active roster | | | Before |
| 8/23/2012 | QUI | Bell,J | Demoted to reserve roster | | | Before |
| 8/23/2012 | QUI | Martinez,J | Promoted to active roster | | | Before |
| 8/23/2012 | QUI | Montero,J | Promoted to active roster | | | Before |
| 8/23/2012 | RLF | Alonso | Promoted to active roster | | | Before |
| 8/23/2012 | RLF | Headley | Promoted to active roster | | | Before |
| 8/23/2012 | RLF | Jenks | Promoted to active roster | | | Before |
| 8/23/2012 | RLF | Robinson,T | Promoted to active roster | | | Before |
| 8/23/2012 | RLF | Sappelt | Promoted to active roster | | | Before |
| 8/23/2012 | RLF | Snider | Promoted to active roster | | | Before |
| 8/23/2012 | RLF | Teheran | Promoted to active roster | | | Before |
| 8/23/2012 | RLF | Tosoni | Promoted to active roster | | | Before |
| 8/23/2012 | RLF | Vasquez,E | Promoted to active roster | | | Before |
| 8/23/2012 | SCO | Cashner | Promoted to active roster | | | Before |
| 8/23/2012 | SCO | Drabek | Promoted to active roster | | | Before |
| 8/23/2012 | SCO | Helton | Promoted to active roster | | | Before |
| 8/23/2012 | SCO | Parmelee | Demoted to reserve roster | | | Before |
| 8/23/2012 | SCO | Parmelee | Promoted to active roster | | | Before |
| 8/23/2012 | SCO | Plouffe | Promoted to active roster | | | Before |
| 8/23/2012 | SCO | Pomeranz | Promoted to active roster | | | Before |
| 8/23/2012 | SCO | Ross,D | Promoted to active roster | | | Before |
| 8/23/2012 | SCO | Ross,T | Demoted to reserve roster | | | Before |
| 8/23/2012 | SCO | Snyder,C | Demoted to reserve roster | | | Before |
| 8/23/2012 | SCO | Taylor | Promoted to active roster | | | Before |
| 8/23/2012 | SKT | Adams,M | Promoted to active roster | | | Before |
| 8/23/2012 | SKT | Blanco,H | Promoted to active roster | | | Before |
| 8/23/2012 | SKT | Evans | Promoted to active roster | | | Before |
| 8/23/2012 | SKT | Francisco,B | Promoted to active roster | | | Before |
| 8/23/2012 | SKT | Gonzalez,M | Promoted to active roster | | | Before |
| 8/23/2012 | SKT | Gregerson | Promoted to active roster | | | Before |
| 8/23/2012 | SKT | Hamilton,J | Promoted to active roster | | | Before |
| 8/23/2012 | SKT | Matsuzaka | Promoted to active roster | | | Before |
| 8/23/2012 | SKT | Overbay | Promoted to active roster | | | Before |
| 8/23/2012 | SKT | Schwinden | Promoted to active roster | | | Before |
| 8/23/2012 | SLG | Beckett | Demoted to reserve roster | | | Before |
| 8/23/2012 | SLG | Boggs,M | Promoted to active roster | | | Before |
| 8/23/2012 | SLG | Bogusevic | Promoted to active roster | | | Before |
| 8/23/2012 | SLG | Brignac | Promoted to active roster | | | Before |
| 8/23/2012 | SLG | Gorzelanny | Promoted to active roster | | | Before |
| 8/23/2012 | SLG | Greene | Promoted to active roster | | | Before |
| 8/23/2012 | SLG | Hayes | Promoted to active roster | | | Before |
| 8/23/2012 | SLG | Huff,D | Promoted to active roster | | | Before |
| 8/23/2012 | SLG | Jurrjens | Demoted to reserve roster | | | Before |
| 8/23/2012 | SLG | Mendoza | Promoted to active roster | | | Before |
| 8/23/2012 | SLG | Presley | Promoted to active roster | | | Before |
| 8/27/2012 | DRI | LaHair | Demoted to reserve roster | | | Before |
| 8/27/2012 | DRI | Perez,S | Demoted to reserve roster | | | Before |
| 8/27/2012 | PEA | Halladay | Demoted to reserve roster | | | Before |
| 8/27/2012 | PEA | Pineiro | Promoted to active roster | | | Before |
| 8/27/2012 | PIN | Castillo,W | Demoted to reserve roster | | | Before |
| 8/27/2012 | PIN | Iglesias | Demoted to reserve roster | | | Before |
| 8/27/2012 | REB | Bedard | Demoted to reserve roster | | | Before |
| 8/27/2012 | REB | Johnson,Jo | Demoted to reserve roster | | | Before |
| 8/28/2012 | B C | LaPorta | Demoted to reserve roster | | | Before |
| 8/28/2012 | B C | Ziegler | Demoted to reserve roster | | | Before |
| 8/28/2012 | DRI | Bastardo | Demoted to reserve roster | | | Before |
| 8/28/2012 | DRI | Giavotella | Demoted to reserve roster | | | Before |
| 8/28/2012 | FOR | Cobb | Promoted to active roster | | | Before |
| 8/28/2012 | FOR | Goldschmidt | Promoted to active roster | | | Before |
| 8/28/2012 | FOR | Posey | Promoted to active roster | | | Before |
| 8/28/2012 | FOR | Richard | Promoted to active roster | | | Before |
| 8/28/2012 | FOR | Wood,Br | Promoted to active roster | | | Before |
| 8/28/2012 | HSX | Brothers | Demoted to reserve roster | | | Before |
| 8/28/2012 | HSX | Buchholz,C | Promoted to active roster | | | Before |
| 8/28/2012 | INP | Aviles | Promoted to active roster | | | Before |
| 8/28/2012 | INP | d'Arnaud | Signed | | | Before |
| 8/28/2012 | INP | DeRosa | Signed | | | Before |
| 8/28/2012 | INP | Dinkelman | Demoted to reserve roster | | | Before |
| 8/28/2012 | INP | Garland | Signed | | | Before |
| 8/28/2012 | INP | Gordon,D | Demoted to reserve roster | | | Before |
| 8/28/2012 | INP | Gordon,D | Promoted to active roster | | | Before |
| 8/28/2012 | INP | Kotsay | Released | | | Before |
| 8/28/2012 | INP | Marshall | Demoted to reserve roster | | | Before |
| 8/28/2012 | INP | Nunez,E | Released | | | Before |
| 8/28/2012 | INP | Nunez,E | Promoted to active roster | | | Before |
| 8/28/2012 | INP | Schafer,L | Released | | | Before |
| 8/28/2012 | MAI | Canzler | Promoted to active roster | | | Before |
| 8/28/2012 | MAI | Eyre | Signed | | | Before |
| 8/28/2012 | MAI | Schlereth | Released | | | Before |
| 8/28/2012 | MAI | Teaford | Promoted to active roster | | | Before |
| 8/28/2012 | MAI | Wood,Tr | Promoted to active roster | | | Before |
| 8/28/2012 | OUT | Johnson,Ro | Released | | | Before |
| 8/28/2012 | OUT | Pauley | Signed | | | Before |
| 8/28/2012 | PEA | Halladay | Promoted to active roster | | | Before |
| 8/28/2012 | PEA | Happ | Demoted to reserve roster | | | Before |
| 8/28/2012 | PEA | Pineiro | Demoted to reserve roster | | | Before |
| 8/28/2012 | PHO | Napoli | Demoted to reserve roster | | | Before |
| 8/28/2012 | QUI | Bell,J | Promoted to active roster | | | Before |
| 8/28/2012 | QUI | Blanton | Promoted to active roster | | | Before |
| 8/28/2012 | QUI | Lombardozzi | Promoted to active roster | | | Before |
| 8/28/2012 | QUI | Montero,J | Demoted to reserve roster | | | Before |
| 8/28/2012 | QUI | Montero,J | Promoted to active roster | | | Before |
| 8/28/2012 | SCO | Bard,J | Signed | | | Before |
| 8/28/2012 | SCO | Parmelee | Released | | | Before |
| 8/28/2012 | SID | Anderson,B | Promoted to active roster | | | Before |
| 8/28/2012 | SID | Davis,C | Promoted to active roster | | | Before |
| 8/28/2012 | SID | Davis,W | Promoted to active roster | | | Before |
| 8/28/2012 | SID | McGowan | Promoted to active roster | | | Before |
| 8/28/2012 | SID | Ondrusek | Promoted to active roster | | | Before |
| 8/28/2012 | SID | Peguero | Promoted to active roster | | | Before |
| 8/28/2012 | SID | Pill | Promoted to active roster | | | Before |
| 8/28/2012 | SLG | Beckett | Promoted to active roster | | | Before |
| 8/28/2012 | SLG | Boggs,M | Demoted to reserve roster | | | Before |
| 8/28/2012 | SLG | Bogusevic | Demoted to reserve roster | | | Before |
| 8/28/2012 | SLG | Brignac | Demoted to reserve roster | | | Before |
| 8/28/2012 | SLG | Cruz,T | Demoted to reserve roster | | | Before |
| 8/28/2012 | SLG | Gorzelanny | Demoted to reserve roster | | | Before |
| 8/28/2012 | SLG | Greene | Demoted to reserve roster | | | Before |
| 8/28/2012 | SLG | Huff,D | Demoted to reserve roster | | | Before |
| 8/28/2012 | SLG | Ibanez | Demoted to reserve roster | | | Before |
| 8/28/2012 | SLG | Jurrjens | Promoted to active roster | | | Before |
| 8/28/2012 | SLG | Mendoza | Demoted to reserve roster | | | Before |
| 8/28/2012 | SYN | Beachy | Promoted to active roster | | | Before |
| 8/28/2012 | SYN | Eovaldi | Promoted to active roster | | | Before |
| 8/28/2012 | SYN | Hamburger | Promoted to active roster | | | Before |
| 8/28/2012 | SYN | Marte | Promoted to active roster | | | Before |
| 8/28/2012 | SYN | Ruffin | Promoted to active roster | | | Before |
| 8/28/2012 | SYN | Surkamp | Promoted to active roster | | | Before |
| 8/28/2012 | SYN | Thompson,R | Promoted to active roster | | | Before |
| 9/1/2012 | BOU | Wells,V | Demoted to reserve roster | | | Before |
| 9/1/2012 | COM | Maier | Demoted to reserve roster | | | Before |
| 9/1/2012 | EAG | Moscoso | Demoted to reserve roster | | | Before |
| 9/1/2012 | EMP | Fiers | Demoted to reserve roster | | | Before |
| 9/1/2012 | EMP | Ordonez | Released | | | Before |
| 9/1/2012 | EMP | Shuck | Signed | | | Before |
| 9/1/2012 | FOR | Barajas | Released | | | Before |
| 9/1/2012 | FOR | Cobb | Demoted to reserve roster | | | Before |
| 9/1/2012 | FOR | Goldschmidt | Demoted to reserve roster | | | Before |
| 9/1/2012 | FOR | Marquis | Demoted to reserve roster | | | Before |
| 9/1/2012 | FOR | Morales,J | Signed | | | Before |
| 9/1/2012 | FOR | Rzepczynski | Demoted to reserve roster | | | Before |
| 9/1/2012 | FOR | Wood,Br | Demoted to reserve roster | | | Before |
| 9/1/2012 | HSX | Brothers | Promoted to active roster | | | Before |
| 9/1/2012 | QUI | Ackley | Demoted to reserve roster | | | Before |
| 9/1/2012 | QUI | Bell,J | Demoted to reserve roster | | | Before |
| 9/1/2012 | QUI | Crawford,B | Demoted to reserve roster | | | Before |
| 9/1/2012 | QUI | Crawford,B | Promoted to active roster | | | Before |
| 9/1/2012 | QUI | Lombardozzi | Demoted to reserve roster | | | Before |
| 9/1/2012 | QUI | Lopez,Jo | Signed | | | Before |
| 9/1/2012 | QUI | Marrero | Demoted to reserve roster | | | Before |
| 9/1/2012 | QUI | Montero,J | Demoted to reserve roster | | | Before |
| 9/1/2012 | QUI | Phelps | Released | | | Before |
| 9/1/2012 | REB | Bedard | Promoted to active roster | | | Before |
| 9/1/2012 | REB | Johnson,Jo | Promoted to active roster | | | Before |
| 9/1/2012 | RLF | Jenks | Demoted to reserve roster | | | Before |
| 9/1/2012 | SLG | Madson | Demoted to reserve roster | | | Before |
| 9/2/2012 | MAI | Canzler | Demoted to reserve roster | | | Before |
| 9/2/2012 | PIN | Sanchez,F | Demoted to reserve roster | | | Before |
| 9/4/2012 | SYN | Bailey,H | Demoted to reserve roster | | | Before |
| 9/4/2012 | SYN | Eovaldi | Demoted to reserve roster | | | Before |
| 9/4/2012 | SYN | Thompson,R | Demoted to reserve roster | | | Before |
| 9/6/2012 | OUT | Blanks | Promoted to active roster | | | Before |
| 9/6/2012 | OUT | Encarnacion | Promoted to active roster | | | Before |
| 9/6/2012 | OUT | Rasmus | Promoted to active roster | | | Before |
| 9/6/2012 | OUT | Young,D | Demoted to reserve roster | | | Before |
| 9/6/2012 | SYN | Hamburger | Demoted to reserve roster | | | Before |
| 9/6/2012 | SYN | Marte | Demoted to reserve roster | | | Before |
| 9/6/2012 | SYN | Richards | Promoted to active roster | | | Before |
| 9/6/2012 | SYN | Zambrano | Demoted to reserve roster | | | Before |
| 9/8/2012 | B C | Cecil | Demoted to reserve roster | | | Before |
| 9/8/2012 | B C | Floyd | Demoted to reserve roster | | | Before |
| 9/8/2012 | B C | LaPorta | Promoted to active roster | | | Before |
| 9/8/2012 | EMP | Braden | Released | | | Before |
| 9/8/2012 | EMP | Gimenez,C | Released | | | Before |
| 9/8/2012 | EMP | Guillen | Signed | | | Before |
| 9/8/2012 | EMP | Vizquel | Signed | | | Before |
| 9/8/2012 | FOR | Gomez,J | Demoted to reserve roster | | | Before |
| 9/8/2012 | FOR | Marquis | Promoted to active roster | | | Before |
| 9/8/2012 | FOR | Posey | Demoted to reserve roster | | | Before |
| 9/8/2012 | FOR | Rzepczynski | Promoted to active roster | | | Before |
| 9/8/2012 | FOR | Wood,Br | Promoted to active roster | | | Before |
| 9/8/2012 | MAI | Alburquerque | Demoted to reserve roster | | | Before |
| 9/8/2012 | MAI | Andino | Demoted to reserve roster | | | Before |
| 9/8/2012 | MAI | Balfour | Demoted to reserve roster | | | Before |
| 9/8/2012 | MAI | Canzler | Released | | | Before |
| 9/8/2012 | MAI | Downs,S | Demoted to reserve roster | | | Before |
| 9/8/2012 | MAI | Downs,S | Promoted to active roster | | | Before |
| 9/8/2012 | MAI | Downs,S | Demoted to reserve roster | | | Before |
| 9/8/2012 | MAI | Gentry | Demoted to reserve roster | | | Before |
| 9/8/2012 | MAI | Hart | Demoted to reserve roster | | | Before |
| 9/8/2012 | MAI | Molina,J | Demoted to reserve roster | | | Before |
| 9/8/2012 | MAI | Stammen | Signed | | | Before |
| 9/8/2012 | MAI | Varvaro | Demoted to reserve roster | | | Before |
| 9/8/2012 | QUI | Ackley | Promoted to active roster | | | Before |
| 9/8/2012 | QUI | Garcia,F | Promoted to active roster | | | Before |
| 9/8/2012 | QUI | Marrero | Promoted to active roster | | | Before |
| 9/8/2012 | QUI | Montero,J | Promoted to active roster | | | Before |
| 9/8/2012 | SCO | LeCure | Demoted to reserve roster | | | Before |
| 9/8/2012 | SCO | Pomeranz | Demoted to reserve roster | | | Before |
| 9/8/2012 | SCO | Taylor | Demoted to reserve roster | | | Before |
| 9/12/2012 | COM | Lillibridge | Demoted to reserve roster | | | Before |
| 9/12/2012 | COM | Martinez,F | Demoted to reserve roster | | | Before |
| 9/12/2012 | COM | Swisher | Demoted to reserve roster | | | Before |
| 9/12/2012 | PIN | Diaz | Demoted to reserve roster | | | Before |
| 9/12/2012 | PIN | Hafner | Demoted to reserve roster | | | Before |
| 9/12/2012 | PIN | Sanchez,F | Demoted to reserve roster | | | Before |
| 9/13/2012 | BOU | Chacin | Demoted to reserve roster | | | Before |
| 9/13/2012 | BOU | Zimmermann | Demoted to reserve roster | | | Before |
| 9/13/2012 | DRI | Cabrera,E | Demoted to reserve roster | | | Before |
| 9/13/2012 | DRI | De La Cruz | Signed | | | Before |
| 9/13/2012 | DRI | Giavotella | Demoted to reserve roster | | | Before |
| 9/13/2012 | DRI | Ka'aihue | Released | | | Before |
| 9/13/2012 | DRI | Nathan | Demoted to reserve roster | | | Before |
| 9/13/2012 | DRI | Peralta,Jo | Demoted to reserve roster | | | Before |
| 9/13/2012 | DRI | Sanchez,H | Demoted to reserve roster | | | Before |
| 9/13/2012 | DRI | Thome | Demoted to reserve roster | | | Before |
| 9/13/2012 | FOR | Goldschmidt | Promoted to active roster | | | Before |
| 9/13/2012 | FOR | Gomez,J | Promoted to active roster | | | Before |
| 9/13/2012 | FOR | Posey | Promoted to active roster | | | Before |
| 9/13/2012 | HSX | Bourgeois | Demoted to reserve roster | | | Before |
| 9/13/2012 | HSX | Brothers | Demoted to reserve roster | | | Before |
| 9/13/2012 | HSX | Porcello | Promoted to active roster | | | Before |
| 9/13/2012 | HSX | Ramirez,M | Demoted to reserve roster | | | Before |
| 9/13/2012 | IRI | Chen | Demoted to reserve roster | | | Before |
| 9/13/2012 | IRI | Chen | Promoted to active roster | | | Before |
| 9/13/2012 | IRI | Ortiz,D | Demoted to reserve roster | | | Before |
| 9/13/2012 | IRI | Wang | Promoted to active roster | | | Before |
| 9/13/2012 | IRI | Weaver | Demoted to reserve roster | | | Before |
| 9/13/2012 | IRI | Wilson,C | Demoted to reserve roster | | | Before |
| 9/13/2012 | IRI | Young,CR | Promoted to active roster | | | Before |
| 9/13/2012 | LEG | Cishek | Demoted to reserve roster | | | Before |
| 9/13/2012 | MAI | Affeldt | Demoted to reserve roster | | | Before |
| 9/13/2012 | MAI | Andino | Promoted to active roster | | | Before |
| 9/13/2012 | MAI | Balfour | Promoted to active roster | | | Before |
| 9/13/2012 | MAI | Downs,S | Promoted to active roster | | | Before |
| 9/13/2012 | MAI | Gentry | Promoted to active roster | | | Before |
| 9/13/2012 | MAI | Hart | Promoted to active roster | | | Before |
| 9/13/2012 | MAI | Holland,G | Promoted to active roster | | | Before |
| 9/13/2012 | MAI | Molina,J | Promoted to active roster | | | Before |
| 9/13/2012 | PEA | Laird,B | Demoted to reserve roster | | | Before |
| 9/13/2012 | PEA | LeMahieu | Demoted to reserve roster | | | Before |
| 9/13/2012 | PEA | Tillman | Demoted to reserve roster | | | Before |
| 9/13/2012 | PHO | Hawkins | Demoted to reserve roster | | | Before |
| 9/13/2012 | PHO | Napoli | Promoted to active roster | | | Before |
| 9/13/2012 | PHO | Punto | Demoted to reserve roster | | | Before |
| 9/13/2012 | PHO | Tazawa | Demoted to reserve roster | | | Before |
| 9/13/2012 | PIN | Ankiel | Demoted to reserve roster | | | Before |
| 9/13/2012 | PIN | Cain,L | Demoted to reserve roster | | | Before |
| 9/13/2012 | PIN | Diaz | Released | | | Before |
| 9/13/2012 | PIN | Michaels | Signed | | | Before |
| 9/13/2012 | PIN | Reddick | Demoted to reserve roster | | | Before |
| 9/13/2012 | PIN | Reddick | Promoted to active roster | | | Before |
| 9/13/2012 | PIN | Sanchez,F | Released | | | Before |
| 9/13/2012 | PIN | Spilborghs | Signed | | | Before |
| 9/13/2012 | SCO | Sizemore,G | Promoted to active roster | | | Before |
| 9/13/2012 | SLG | Benoit | Demoted to reserve roster | | | Before |
| 9/13/2012 | SLG | Huff,D | Released | | | Before |
| 9/13/2012 | SLG | Kelley | Signed | | | Before |
| 9/13/2012 | SLG | Mendoza | Released | | | Before |
| 9/13/2012 | SLG | Salas | Demoted to reserve roster | | | Before |
| 9/13/2012 | SLG | Santiago,H | Signed | | | Before |
| 9/13/2012 | SYN | Eovaldi | Promoted to active roster | | | Before |
| 9/16/2012 | FOR | Posey | Demoted to reserve roster | | | Before |
| 9/16/2012 | FOR | Posey | Promoted to active roster | | | Before |
| 9/16/2012 | MAI | Altuve | Demoted to reserve roster | | | Before |
| 9/16/2012 | MAI | Altuve | Promoted to active roster | | | Before |
| 9/16/2012 | MAI | Bloomquist | Demoted to reserve roster | | | Before |
| 9/16/2012 | MAI | Bloomquist | Promoted to active roster | | | Before |
| 9/16/2012 | MAI | Gentry | Demoted to reserve roster | | | Before |
| 9/16/2012 | MAI | Gentry | Promoted to active roster | | | Before |
| 9/16/2012 | MAI | Hart | Demoted to reserve roster | | | Before |
| 9/16/2012 | MAI | Hart | Promoted to active roster | | | Before |
| 9/16/2012 | MAI | Molina,J | Demoted to reserve roster | | | Before |
| 9/16/2012 | MAI | Molina,J | Promoted to active roster | | | Before |
| 9/16/2012 | MAI | Pence | Demoted to reserve roster | | | Before |
| 9/16/2012 | MAI | Pence | Promoted to active roster | | | Before |
| 9/16/2012 | MAI | Pierre | Demoted to reserve roster | | | Before |
| 9/16/2012 | MAI | Pierre | Promoted to active roster | | | Before |
| 9/17/2012 | B C | Belt | Demoted to reserve roster | | | Before |
| 9/17/2012 | B C | Cecil | Promoted to active roster | | | Before |
| 9/17/2012 | B C | Matusz | Demoted to reserve roster | | | Before |
| 9/17/2012 | B C | Morrison | Demoted to reserve roster | | | Before |
| 9/17/2012 | B C | Sweeney | Demoted to reserve roster | | | Before |
| 9/17/2012 | REB | Peavy | Demoted to reserve roster | | | Before |
| 9/18/2012 | BOU | Chavez,En | Promoted to active roster | | | Before |
| 9/18/2012 | BOU | Constanza | Released | | | Before |
| 9/18/2012 | BOU | Martinez,M | Signed | | | Before |
| 9/18/2012 | BOU | Ortiz,R | Signed | | | Before |
| 9/18/2012 | BOU | Parker | Promoted to active roster | | | Before |
| 9/18/2012 | BOU | Penny | Demoted to reserve roster | | | Before |
| 9/18/2012 | BOU | Renteria | Released | | | Before |
| 9/18/2012 | BOU | Rios | Demoted to reserve roster | | | Before |
| 9/18/2012 | BOU | Scott | Demoted to reserve roster | | | Before |
| 9/18/2012 | COM | Doubront | Promoted to active roster | | | Before |
| 9/18/2012 | COM | Martinez,F | Promoted to active roster | | | Before |
| 9/18/2012 | EAG | Guthrie | Demoted to reserve roster | | | Before |
| 9/18/2012 | EMP | Nix,L | Demoted to reserve roster | | | Before |
| 9/18/2012 | EMP | Reed,A | Demoted to reserve roster | | | Before |
| 9/18/2012 | FOR | Cobb | Promoted to active roster | | | Before |
| 9/18/2012 | FOR | Posey | Demoted to reserve roster | | | Before |
| 9/18/2012 | FOR | Posey | Promoted to active roster | | | Before |
| 9/18/2012 | FOR | Richard | Demoted to reserve roster | | | Before |
| 9/18/2012 | FOR | Rzepczynski | Demoted to reserve roster | | | Before |
| 9/18/2012 | HSX | Bourgeois | Promoted to active roster | | | Before |
| 9/18/2012 | HSX | Brothers | Promoted to active roster | | | Before |
| 9/18/2012 | INP | Diamond | Signed | | | Before |
| 9/18/2012 | INP | Dinkelman | Released | | | Before |
| 9/18/2012 | INP | Godfrey | Released | | | Before |
| 9/18/2012 | INP | Lincoln | Signed | | | Before |
| 9/18/2012 | INP | Melancon | Released | | | Before |
| 9/18/2012 | INP | Sanabia | Signed | | | Before |
| 9/18/2012 | IRI | Chen | Demoted to reserve roster | | | Before |
| 9/18/2012 | IRI | McDonald,Ja | Demoted to reserve roster | | | Before |
| 9/18/2012 | IRI | Navarro,Y | Signed | | | Before |
| 9/18/2012 | IRI | Tatum | Released | | | Before |
| 9/18/2012 | IRI | Weaver | Promoted to active roster | | | Before |
| 9/18/2012 | IRI | Wilson,C | Promoted to active roster | | | Before |
| 9/18/2012 | MAI | Altuve | Demoted to reserve roster | | | Before |
| 9/18/2012 | MAI | Ciriaco | Signed | | | Before |
| 9/18/2012 | MAI | Dickerson | Signed | | | Before |
| 9/18/2012 | MAI | Donald | Released | | | Before |
| 9/18/2012 | MAI | Gentry | Demoted to reserve roster | | | Before |
| 9/18/2012 | MAI | Hart | Demoted to reserve roster | | | Before |
| 9/18/2012 | MAI | Maholm | Demoted to reserve roster | | | Before |
| 9/18/2012 | MAI | Molina,J | Released | | | Before |
| 9/18/2012 | MAI | Pence | Demoted to reserve roster | | | Before |
| 9/18/2012 | MAI | Pierre | Demoted to reserve roster | | | Before |
| 9/18/2012 | MAI | Ruggiano | Signed | | | Before |
| 9/18/2012 | MAI | Saito | Released | | | Before |
| 9/18/2012 | OUT | Harris | Released | | | Before |
| 9/18/2012 | OUT | Paul | Signed | | | Before |
| 9/18/2012 | PHO | Baker,Je | Demoted to reserve roster | | | Before |
| 9/18/2012 | PHO | Belisle | Demoted to reserve roster | | | Before |
| 9/18/2012 | PHO | Belisle | Promoted to active roster | | | Before |
| 9/18/2012 | PHO | Duncan | Demoted to reserve roster | | | Before |
| 9/18/2012 | PHO | Hamels | Demoted to reserve roster | | | Before |
| 9/18/2012 | PHO | Hawkins | Promoted to active roster | | | Before |
| 9/18/2012 | PHO | Kubel | Demoted to reserve roster | | | Before |
| 9/18/2012 | PHO | Martinez,C | Demoted to reserve roster | | | Before |
| 9/18/2012 | PHO | Martinez,C | Promoted to active roster | | | Before |
| 9/18/2012 | PHO | Napoli | Demoted to reserve roster | | | Before |
| 9/18/2012 | PHO | Upton,B | Demoted to reserve roster | | | Before |
| 9/18/2012 | QUI | Bell,J | Promoted to active roster | | | Before |
| 9/18/2012 | QUI | Coffey | Demoted to reserve roster | | | Before |
| 9/18/2012 | QUI | Gamel | Promoted to active roster | | | Before |
| 9/18/2012 | QUI | Liddi | Promoted to active roster | | | Before |
| 9/18/2012 | QUI | Lombardozzi | Promoted to active roster | | | Before |
| 9/18/2012 | QUI | Lyles | Promoted to active roster | | | Before |
| 9/18/2012 | SCO | Bourjos | Demoted to reserve roster | | | Before |
| 9/18/2012 | SCO | Carrasco,C | Promoted to active roster | | | Before |
| 9/18/2012 | SCO | Cashner | Demoted to reserve roster | | | Before |
| 9/18/2012 | SCO | Pena,W | Signed | | | Before |
| 9/18/2012 | SCO | Ross,D | Released | | | Before |
| 9/18/2012 | SCO | Ross,D | Signed | | | Before |
| 9/18/2012 | SCO | Ross,T | Released | | | Before |
| 9/18/2012 | SCO | Sizemore,G | Demoted to reserve roster | | | Before |
| 9/18/2012 | SLG | Benoit | Promoted to active roster | | | Before |
| 9/18/2012 | SLG | Madson | Promoted to active roster | | | Before |
| 9/18/2012 | SLG | Salas | Promoted to active roster | | | Before |
| 9/18/2012 | SYN | Eovaldi | Demoted to reserve roster | | | Before |
| 9/18/2012 | SYN | Uehara | Demoted to reserve roster | | | Before |
| 9/19/2012 | COM | Martinez,F | Demoted to reserve roster | | | Before |
| 9/20/2012 | REB | Medlen | Demoted to reserve roster | | | Before |
| 9/20/2012 | SLG | Benoit | Demoted to reserve roster | | | Before |
| 9/20/2012 | SLG | Madson | Demoted to reserve roster | | | Before |
| 9/20/2012 | SLG | Salas | Demoted to reserve roster | | | Before |
| 9/21/2012 | REB | DeJesus | Demoted to reserve roster | | | Before |
| 9/21/2012 | REB | DeJesus | Promoted to active roster | | | Before |
| 9/21/2012 | REB | Kipnis | Demoted to reserve roster | | | Before |
| 9/21/2012 | REB | Ramos,W | Demoted to reserve roster | | | Before |
| 9/22/2012 | COM | Adams,R | Demoted to reserve roster | | | Before |
| 9/22/2012 | COM | Balester | Demoted to reserve roster | | | Before |
| 9/22/2012 | COM | Doubront | Demoted to reserve roster | | | Before |
| 9/22/2012 | COM | Federowicz | Demoted to reserve roster | | | Before |
| 9/22/2012 | COM | Forsythe | Demoted to reserve roster | | | Before |
| 9/22/2012 | COM | Jeffress | Demoted to reserve roster | | | Before |
| 9/22/2012 | COM | Lillibridge | Promoted to active roster | | | Before |
| 9/22/2012 | COM | Lowe,D | Demoted to reserve roster | | | Before |
| 9/22/2012 | COM | Maier | Promoted to active roster | | | Before |
| 9/22/2012 | COM | Nelson | Demoted to reserve roster | | | Before |
| 9/22/2012 | COM | Roberts,B | Demoted to reserve roster | | | Before |
| 9/22/2012 | COM | Roberts,B | Promoted to active roster | | | Before |
| 9/22/2012 | COM | Strop | Demoted to reserve roster | | | Before |
| 9/22/2012 | COM | Swisher | Promoted to active roster | | | Before |
| 9/22/2012 | LEG | Broxton | Demoted to reserve roster | | | Before |
| 9/22/2012 | LEG | Carter | Demoted to reserve roster | | | Before |
| 9/22/2012 | LEG | Cueto | Demoted to reserve roster | | | Before |
| 9/22/2012 | LEG | Gutierrez,J | Demoted to reserve roster | | | Before |
| 9/22/2012 | LEG | Jackson,C | Demoted to reserve roster | | | Before |
| 9/22/2012 | LEG | Kalish | Demoted to reserve roster | | | Before |
| 9/22/2012 | LEG | Lee,D | Demoted to reserve roster | | | Before |
| 9/22/2012 | LEG | Pelfrey | Demoted to reserve roster | | | Before |
| 9/22/2012 | LEG | Spence | Demoted to reserve roster | | | Before |
| 9/22/2012 | LEG | Spence | Promoted to active roster | | | Before |
| 9/22/2012 | LEG | Spence | Demoted to reserve roster | | | Before |
| 9/22/2012 | LEG | Volstad | Demoted to reserve roster | | | Before |
| 9/22/2012 | SCO | Ross,D | Signed | | | Before |
| 9/22/2012 | SCO | Ross,T | Released | | | Before |
| 9/24/2012 | EAG | Alfonzo | Demoted to reserve roster | | | Before |
| 9/24/2012 | EAG | Beavan | Demoted to reserve roster | | | Before |
| 9/24/2012 | EAG | Bell,H | Demoted to reserve roster | | | Before |
| 9/24/2012 | EAG | Campana | Promoted to active roster | | | Before |
| 9/24/2012 | EAG | Gregg | Demoted to reserve roster | | | Before |
| 9/24/2012 | EAG | Guthrie | Promoted to active roster | | | Before |
| 9/24/2012 | EAG | Janish | Demoted to reserve roster | | | Before |
| 9/24/2012 | EAG | Lackey | Demoted to reserve roster | | | Before |
| 9/24/2012 | EAG | Maldonado | Demoted to reserve roster | | | Before |
| 9/24/2012 | EAG | Miley | Demoted to reserve roster | | | Before |
| 9/24/2012 | EAG | Moscoso | Promoted to active roster | | | Before |
| 9/24/2012 | EAG | Mota | Demoted to reserve roster | | | Before |
| 9/24/2012 | EAG | Mota | Promoted to active roster | | | Before |
| 9/24/2012 | EAG | Pacheco | Demoted to reserve roster | | | Before |
| 9/24/2012 | EAG | Rodney | Demoted to reserve roster | | | Before |
| 9/24/2012 | HSX | Blevins | Demoted to reserve roster | | | Before |
| 9/24/2012 | HSX | Burnett,AJ | Demoted to reserve roster | | | Before |
| 9/24/2012 | HSX | Colvin | Demoted to reserve roster | | | Before |
| 9/24/2012 | HSX | Flowers | Demoted to reserve roster | | | Before |
| 9/24/2012 | HSX | Guyer | Demoted to reserve roster | | | Before |
| 9/24/2012 | HSX | Hughes,P | Demoted to reserve roster | | | Before |
| 9/24/2012 | HSX | Litsch | Demoted to reserve roster | | | Before |
| 9/24/2012 | HSX | Porcello | Demoted to reserve roster | | | Before |
| 9/24/2012 | IRI | Amarista | Demoted to reserve roster | | | Before |
| 9/24/2012 | IRI | Chen | Promoted to active roster | | | Before |
| 9/24/2012 | IRI | Coghlan | Demoted to reserve roster | | | Before |
| 9/24/2012 | IRI | Fontenot | Demoted to reserve roster | | | Before |
| 9/24/2012 | IRI | Lind | Demoted to reserve roster | | | Before |
| 9/24/2012 | IRI | Mesoraco | Demoted to reserve roster | | | Before |
| 9/24/2012 | IRI | Navarro,Y | Demoted to reserve roster | | | Before |
| 9/24/2012 | IRI | Ortiz,D | Promoted to active roster | | | Before |
| 9/24/2012 | IRI | Shaw | Demoted to reserve roster | | | Before |
| 9/24/2012 | IRI | Wang | Demoted to reserve roster | | | Before |
| 9/24/2012 | IRI | Young,CR | Demoted to reserve roster | | | Before |
| 9/24/2012 | PHO | Abreu,B | Demoted to reserve roster | | | Before |
| 9/24/2012 | PHO | Baker,Je | Demoted to reserve roster | | | Before |
| 9/24/2012 | PHO | Baker,Je | Promoted to active roster | | | Before |
| 9/24/2012 | PHO | Colon | Demoted to reserve roster | | | Before |
| 9/24/2012 | PHO | Duncan | Promoted to active roster | | | Before |
| 9/24/2012 | PHO | Hamels | Promoted to active roster | | | Before |
| 9/24/2012 | PHO | Johnson,C | Demoted to reserve roster | | | Before |
| 9/24/2012 | PHO | Johnson,E | Demoted to reserve roster | | | Before |
| 9/24/2012 | PHO | Keppinger | Demoted to reserve roster | | | Before |
| 9/24/2012 | PHO | Kubel | Promoted to active roster | | | Before |
| 9/24/2012 | PHO | Lewis,C | Demoted to reserve roster | | | Before |
| 9/24/2012 | PHO | Napoli | Promoted to active roster | | | Before |
| 9/24/2012 | PHO | Posada | Demoted to reserve roster | | | Before |
| 9/24/2012 | PHO | Powell | Demoted to reserve roster | | | Before |
| 9/24/2012 | PHO | Punto | Promoted to active roster | | | Before |
| 9/24/2012 | PHO | Upton,B | Promoted to active roster | | | Before |
| 9/24/2012 | SCO | Bard,J | Demoted to reserve roster | | | Before |
| 9/24/2012 | SCO | Bernadina | Demoted to reserve roster | | | Before |
| 9/24/2012 | SCO | Bourjos | Promoted to active roster | | | Before |
| 9/24/2012 | SCO | Drabek | Demoted to reserve roster | | | Before |
| 9/24/2012 | SCO | Lannan | Demoted to reserve roster | | | Before |
| 9/24/2012 | SCO | LeCure | Promoted to active roster | | | Before |
| 9/24/2012 | SCO | Pena,W | Demoted to reserve roster | | | Before |
| 9/24/2012 | SCO | Sizemore,G | Promoted to active roster | | | Before |
| 9/24/2012 | SCO | Snyder,C | Promoted to active roster | | | Before |
| 9/24/2012 | SCO | Valdez,W | Demoted to reserve roster | | | Before |
| 9/24/2012 | SLG | Benoit | Promoted to active roster | | | Before |
| 9/24/2012 | SLG | Boggs,M | Demoted to reserve roster | | | Before |
| 9/24/2012 | SLG | Bogusevic | Demoted to reserve roster | | | Before |
| 9/24/2012 | SLG | Brignac | Demoted to reserve roster | | | Before |
| 9/24/2012 | SLG | Cruz,T | Demoted to reserve roster | | | Before |
| 9/24/2012 | SLG | Garcia,J | Demoted to reserve roster | | | Before |
| 9/24/2012 | SLG | Greene | Demoted to reserve roster | | | Before |
| 9/24/2012 | SLG | Kelley | Demoted to reserve roster | | | Before |
| 9/24/2012 | SLG | Madson | Promoted to active roster | | | Before |
| 9/24/2012 | SLG | Salas | Promoted to active roster | | | Before |
| 9/24/2012 | SLG | Santiago,H | Demoted to reserve roster | | | Before |
| 9/24/2012 | SLG | Venable | Demoted to reserve roster | | | Before |