| Transactions |
| Date | Team | Player | Type | OthTm | EffDate | When |
| 4/8/2012 | MON | Gonzalez,Ma | Promoted to active roster | | | Before |
| 4/8/2012 | MON | Kottaras,G | Demoted to reserve roster | | | Before |
| 4/8/2012 | MON | Martin | Promoted to active roster | | | Before |
| 4/8/2012 | MON | Rutledge | Demoted to reserve roster | | | Before |
| 4/11/2012 | AVA | Storey | Promoted to active roster | | | Before |
| 4/11/2012 | AVA | Uribe | Demoted to reserve roster | | | Before |
| 4/11/2012 | DSP | Morse | Placed on disabled list | | 4/9/2012 | Before |
| 4/11/2012 | DSP | Reimold | Promoted to active roster | | | Before |
| 4/14/2012 | PEA | Buchholz | Placed on disabled list | | 4/14/2012 | Before |
| 4/14/2012 | PEA | Swarzak | Promoted to active roster | | | Before |
| 4/14/2012 | TOR | Hughes,P | Placed on disabled list | | 4/13/2012 | Before |
| 4/14/2012 | TOR | Karstens | Promoted to active roster | | | Before |
| 4/17/2012 | AVA | Price | Placed on disabled list | | 4/16/2012 | Before |
| 4/17/2012 | AVA | Uribe | Promoted to active roster | | | Before |
| 4/17/2012 | NHP | Harvey | Promoted to active roster | | | Before |
| 4/17/2012 | NHP | Rodriguez,S | Demoted to reserve roster | | | Before |
| 4/20/2012 | TOR | Kearns | Demoted to reserve roster | | | Before |
| 4/20/2012 | TOR | Schumaker | Promoted to active roster | | | Before |
| 4/23/2012 | NHP | Crisp | Placed on disabled list | | 4/18/2012 | Before |
| 4/23/2012 | NHP | Rodriguez,S | Promoted to active roster | | | Before |
| 4/26/2012 | BBK | Davis,R | Placed on disabled list | | 4/25/2012 | Before |
| 4/26/2012 | BBK | Eaton | Promoted to active roster | | | Before |
| 4/26/2012 | WTB | Arias | Promoted to active roster | | | Before |
| 4/26/2012 | WTB | Willingham | Placed on disabled list | | 4/25/2012 | Before |
| 4/29/2012 | AVA | Capps,M | Promoted to active roster | | | Before |
| 4/29/2012 | AVA | Uribe | Demoted to reserve roster | | | Before |
| 4/29/2012 | DSP | Flores | Placed on disabled list | | 4/29/2012 | Before |
| 4/29/2012 | DSP | Hayes | Promoted to active roster | | | Before |
| 4/29/2012 | NHP | Garcia,A | Promoted to active roster | | | Before |
| 4/29/2012 | NHP | Harvey | Demoted to reserve roster | | | Before |
| 4/29/2012 | TOR | Hughes,P | Activated from disabled list | | | Before |
| 4/29/2012 | TOR | Karstens | Demoted to reserve roster | | | Before |
| 5/1/2012 | DEG | Lincoln,B | Traded away | DUR | | After |
| 5/1/2012 | DEG | Lyles | Acquired via trade | DUR | | After |
| 5/1/2012 | DEG | Smith,W | Traded away | DUR | | After |
| 5/2/2012 | AVA | Price | Activated from disabled list | | | Before |
| 5/2/2012 | AVA | Storey | Demoted to reserve roster | | | Before |
| 5/2/2012 | TOR | Karstens | Promoted to active roster | | | Before |
| 5/2/2012 | TOR | Tillman | Placed on disabled list | | 5/2/2012 | Before |
| 5/5/2012 | DEG | Keuchel | Promoted to active roster | | | Before |
| 5/5/2012 | DEG | Peralta,W | Promoted to active roster | | | Before |
| 5/5/2012 | DEG | Robinson,T | Demoted to reserve roster | | | Before |
| 5/5/2012 | DEG | Santana,E | Placed on disabled list | | 5/5/2012 | Before |
| 5/5/2012 | MON | Doubront | Promoted to active roster | | | Before |
| 5/5/2012 | MON | Fiers | Placed on disabled list | | 5/3/2012 | Before |
| 5/5/2012 | NHP | Crisp | Activated from disabled list | | | Before |
| 5/5/2012 | NHP | Garcia,A | Demoted to reserve roster | | | Before |
| 5/5/2012 | PEA | Buchholz | Activated from disabled list | | | Before |
| 5/5/2012 | PEA | Haren | Placed on disabled list | | 5/5/2012 | Before |
| 5/5/2012 | TOR | Kearns | Promoted to active roster | | | Before |
| 5/5/2012 | TOR | Schumaker | Demoted to reserve roster | | | Before |
| 5/8/2012 | DEG | Floyd | Placed on disabled list | | 5/7/2012 | Before |
| 5/8/2012 | DEG | Lyles | Promoted to active roster | | | Before |
| 5/10/2012 | DSP | Lough | Traded away | MAN | | After |
| 5/10/2012 | DSP | Pearce,S | Acquired via trade | MAN | | After |
| 5/10/2012 | NHP | Hughes,J | Acquired via trade | MAN | | After |
| 5/11/2012 | BBK | Davis,R | Activated from disabled list | | | Before |
| 5/11/2012 | BBK | Eaton | Demoted to reserve roster | | | Before |
| 5/11/2012 | DSP | Adams,Mi | Demoted to reserve roster | | | Before |
| 5/11/2012 | DSP | Rodriguez,H | Promoted to active roster | | | Before |
| 5/11/2012 | NHP | Bass | Demoted to reserve roster | | | Before |
| 5/11/2012 | NHP | Gonzalez,Mig | Demoted to reserve roster | | | Before |
| 5/11/2012 | NHP | Gonzalez,Mig | Promoted to active roster | | | Before |
| 5/11/2012 | NHP | Harvey | Promoted to active roster | | | Before |
| 5/11/2012 | WCM | Bloomquist | Promoted to active roster | | | Before |
| 5/11/2012 | WCM | Markakis | Placed on disabled list | | 5/7/2012 | Before |
| 5/11/2012 | WTB | Arias | Demoted to reserve roster | | | Before |
| 5/11/2012 | WTB | Willingham | Activated from disabled list | | | Before |
| 5/14/2012 | DSP | Venable | Placed on disabled list | | 5/9/2012 | Before |
| 5/14/2012 | MON | Cobb | Placed on disabled list | | 5/10/2012 | Before |
| 5/14/2012 | MON | Delgado | Promoted to active roster | | | Before |
| 5/17/2012 | DSP | Flores | Activated from disabled list | | | Before |
| 5/17/2012 | DSP | Ross,D | Demoted to reserve roster | | | Before |
| 5/17/2012 | NHP | Garcia | Demoted to reserve roster | | | Before |
| 5/17/2012 | TOR | Fien | Demoted to reserve roster | | | Before |
| 5/17/2012 | TOR | Locke | Promoted to active roster | | | Before |
| 5/19/2012 | DSP | Cardenas | Traded away | MAN | | After |
| 5/19/2012 | DSP | Herrera | Acquired via trade | MAN | | After |
| 5/19/2012 | WTB | Belisle | Traded away | MAN | | After |
| 5/19/2012 | WTB | Fife | Traded away | MAN | | After |
| 5/19/2012 | WTB | Hardy | Acquired via trade | MAN | | After |
| 5/19/2012 | WTB | Schlereth | Traded away | MAN | | After |
| 5/19/2012 | WTB | Sierra | Traded away | MAN | | After |
| 5/20/2012 | DSP | Hanrahan | Demoted to reserve roster | | | Before |
| 5/20/2012 | DSP | Morse | Activated from disabled list | | | Before |
| 5/20/2012 | MON | Delgado | Demoted to reserve roster | | | Before |
| 5/20/2012 | MON | Fiers | Activated from disabled list | | | Before |
| 5/22/2012 | DSP | Forsythe | Traded away | DUR | | After |
| 5/22/2012 | DSP | McDonald,Jo | Acquired via trade | DUR | | After |
| 5/23/2012 | DEG | Santana,E | Activated from disabled list | | | Before |
| 5/23/2012 | DEG | Sheets | Demoted to reserve roster | | | Before |
| 5/23/2012 | DSP | McDonald,Jo | Demoted to reserve roster | | | Before |
| 5/25/2012 | MON | Crosby | Acquired via trade | DUR | | After |
| 5/25/2012 | MON | Crosby | Acquired via trade | DUR | | After |
| 5/25/2012 | MON | Gonzalez,Ma | Traded away | CGS | | After |
| 5/25/2012 | MON | Lobaton | Traded away | CGS | | After |
| 5/25/2012 | MON | Lobaton | Traded away | CGS | | After |
| 5/25/2012 | MON | Lobaton | Acquired via trade | DUR | | After |
| 5/25/2012 | MON | Lobaton | Acquired via trade | DUR | | After |
| 5/25/2012 | MON | Martin | Traded away | DUR | | After |
| 5/25/2012 | MON | Martin | Traded away | DUR | | After |
| 5/26/2012 | DSP | Drew,S | Demoted to reserve roster | | | Before |
| 5/26/2012 | DSP | Venable | Activated from disabled list | | | Before |
| 5/26/2012 | MON | Cobb | Activated from disabled list | | | Before |
| 5/26/2012 | MON | Doubront | Demoted to reserve roster | | | Before |
| 5/26/2012 | MON | Kottaras,G | Promoted to active roster | | | Before |
| 5/26/2012 | MON | Lobaton | Demoted to reserve roster | | | Before |
| 5/26/2012 | MON | Quintanilla,O | Promoted to active roster | | | Before |
| 5/28/2012 | MON | Gonzalez,Ma | Traded away | CGS | | After |
| 5/29/2012 | DEG | Floyd | Activated from disabled list | | | Before |
| 5/29/2012 | DEG | Keuchel | Demoted to reserve roster | | | Before |
| 5/29/2012 | MON | Cobb | Activated from disabled list | | | Before |
| 5/29/2012 | MON | Doubront | Demoted to reserve roster | | | Before |
| 5/29/2012 | MON | Kottaras,G | Promoted to active roster | | | Before |
| 5/29/2012 | MON | Quintanilla,O | Promoted to active roster | | | Before |
| 6/1/2012 | DSP | Hayes | Demoted to reserve roster | | | Before |
| 6/1/2012 | DSP | Ross,D | Promoted to active roster | | | Before |
| 6/1/2012 | NHP | Bass | Demoted to reserve roster | | | Before |
| 6/1/2012 | NHP | Harvey | Promoted to active roster | | | Before |
| 6/1/2012 | PEA | Quintero | Promoted to active roster | | | Before |
| 6/1/2012 | PEA | Soto,G | Placed on disabled list | | 5/30/2012 | Before |
| 6/1/2012 | TOR | Fien | Promoted to active roster | | | Before |
| 6/1/2012 | TOR | Hughes,P | Demoted to reserve roster | | | Before |
| 6/1/2012 | TOR | Locke | Demoted to reserve roster | | | Before |
| 6/1/2012 | TOR | Tillman | Activated from disabled list | | | Before |
| 6/1/2012 | WTB | Lee,Cl | Placed on disabled list | | 5/31/2012 | Before |
| 6/1/2012 | WTB | Volstad | Promoted to active roster | | | Before |
| 6/4/2012 | AVA | Holland,D | Placed on disabled list | | 6/4/2012 | Before |
| 6/4/2012 | AVA | Uribe | Promoted to active roster | | | Before |
| 6/4/2012 | DEG | Gorzelanny | Placed on disabled list | | 6/3/2012 | Before |
| 6/4/2012 | DEG | Keuchel | Promoted to active roster | | | Before |
| 6/4/2012 | NHP | Bass | Promoted to active roster | | | Before |
| 6/4/2012 | NHP | Harvey | Demoted to reserve roster | | | Before |
| 6/4/2012 | TOR | Hughes,P | Promoted to active roster | | | Before |
| 6/4/2012 | TOR | Norris,B | Demoted to reserve roster | | | Before |
| 6/4/2012 | WTB | Arias | Promoted to active roster | | | Before |
| 6/4/2012 | WTB | Dominguez | Demoted to reserve roster | | | Before |
| 6/7/2012 | DSP | Corbin | Placed on disabled list | | 6/2/2012 | Before |
| 6/7/2012 | DSP | Villanueva | Promoted to active roster | | | Before |
| 6/7/2012 | NHP | Bass | Demoted to reserve roster | | | Before |
| 6/7/2012 | NHP | Harvey | Promoted to active roster | | | Before |
| 6/7/2012 | PEA | Haren | Activated from disabled list | | | Before |
| 6/7/2012 | PEA | Swarzak | Demoted to reserve roster | | | Before |
| 6/10/2012 | TOR | Kearns | Demoted to reserve roster | | | Before |
| 6/10/2012 | TOR | Schumaker | Promoted to active roster | | | Before |
| 6/13/2012 | AVA | Hart | Placed on disabled list | | 6/11/2012 | Before |
| 6/13/2012 | AVA | Kalish | Promoted to active roster | | | Before |
| 6/16/2012 | TOR | Karstens | Demoted to reserve roster | | | Before |
| 6/16/2012 | TOR | Norris,B | Promoted to active roster | | | Before |
| 6/19/2012 | DSP | Corbin | Activated from disabled list | | | Before |
| 6/19/2012 | DSP | Reimold | Demoted to reserve roster | | | Before |
| 6/19/2012 | TOR | Locke | Promoted to active roster | | | Before |
| 6/19/2012 | TOR | Stammen | Placed on disabled list | | 6/18/2012 | Before |
| 6/21/2012 | PAW | Green,Ta | Acquired via trade | TOR | | After |
| 6/21/2012 | TOR | Green,Ta | Traded away | PAW | | After |
| 6/22/2012 | AVA | Capps,M | Demoted to reserve roster | | | Before |
| 6/22/2012 | AVA | Holland,D | Activated from disabled list | | | Before |
| 6/22/2012 | PEA | Quintero | Demoted to reserve roster | | | Before |
| 6/22/2012 | PEA | Soto,G | Activated from disabled list | | | Before |
| 6/22/2012 | WTB | Lee,Cl | Activated from disabled list | | | Before |
| 6/22/2012 | WTB | Volstad | Demoted to reserve roster | | | Before |
| 6/27/2012 | NHP | DeJesus,D | Traded away | DUR | | After |
| 6/27/2012 | NHP | Pagan | Acquired via trade | DUR | | After |
| 6/28/2012 | AVA | Hart | Activated from disabled list | | | Before |
| 6/28/2012 | AVA | Kalish | Demoted to reserve roster | | | Before |
| 6/28/2012 | NHP | Garcia | Promoted to active roster | | | Before |
| 6/28/2012 | NHP | Harvey | Demoted to reserve roster | | | Before |
| 7/8/2012 | AVA | Capps,M | Promoted to active roster | | | Before |
| 7/8/2012 | AVA | Price | Placed on disabled list | | 6/30/2012 | Before |
| 7/8/2012 | NHP | Bass | Promoted to active roster | | | Before |
| 7/8/2012 | NHP | Garcia | Demoted to reserve roster | | | Before |
| 7/8/2012 | PAW | Aumont | Demoted to reserve roster | | | Before |
| 7/8/2012 | PAW | Corporan | Demoted to reserve roster | | | Before |
| 7/8/2012 | WCM | Farnsworth | Demoted to reserve roster | | | Before |
| 7/8/2012 | WCM | Nix,L | Demoted to reserve roster | | | Before |
| 7/8/2012 | WTB | Niese | Placed on disabled list | | 7/1/2012 | Before |
| 7/8/2012 | WTB | Volstad | Promoted to active roster | | | Before |
| 7/10/2012 | DEG | Furbush | Traded away | PBC | | After |
| 7/10/2012 | TOR | Chavez,Er | Acquired via trade | DUR | | After |
| 7/10/2012 | TOR | Kennedy.A | Traded away | DUR | | After |
| 7/10/2012 | TOR | Lewis,C | Acquired via trade | DUR | | After |
| 7/10/2012 | TOR | Norris,B | Traded away | DUR | | After |
| 7/10/2012 | TOR | Wright,W | Acquired via trade | DUR | | After |
| 7/10/2012 | WTB | Avilan | Traded away | CLE | | After |
| 7/10/2012 | WTB | Betemit | Traded away | CLE | | After |
| 7/10/2012 | WTB | Blackburn | Acquired via trade | CLE | | After |
| 7/10/2012 | WTB | Blackley,T | Acquired via trade | MAN | | After |
| 7/10/2012 | WTB | Capuano | Traded away | CLE | | After |
| 7/10/2012 | WTB | Cruz,L | Traded away | CLE | | After |
| 7/10/2012 | WTB | Escobar,Y | Traded away | CLE | | After |
| 7/10/2012 | WTB | Font | Traded away | MAN | | After |
| 7/10/2012 | WTB | Halladay | Acquired via trade | CLE | | After |
| 7/10/2012 | WTB | Hardy | Traded away | PBC | | After |
| 7/10/2012 | WTB | Hochevar | Acquired via trade | CLE | | After |
| 7/10/2012 | WTB | Hudson,O | Acquired via trade | CLE | | After |
| 7/10/2012 | WTB | Johnson,Jo | Traded away | CLE | | After |
| 7/10/2012 | WTB | Johnson,K | Acquired via trade | CLE | | After |
| 7/10/2012 | WTB | Johnson,Re | Acquired via trade | PBC | | After |
| 7/10/2012 | WTB | Mayberry | Acquired via trade | CLE | | After |
| 7/10/2012 | WTB | Putz | Traded away | CLE | | After |
| 7/10/2012 | WTB | Trout | Traded away | CLE | | After |
| 7/10/2012 | WTB | Utley | Traded away | CLE | | After |
| 7/10/2012 | WTB | Volstad | Traded away | CLE | | After |
| 7/10/2012 | WTB | Willingham | Traded away | CLE | | After |
| 7/11/2012 | DEG | Gorzelanny | Activated from disabled list | | | Before |
| 7/11/2012 | NHP | Bass | Demoted to reserve roster | | | Before |
| 7/11/2012 | NHP | Garcia | Promoted to active roster | | | Before |
| 7/11/2012 | NHP | Harvey | Promoted to active roster | | | Before |
| 7/11/2012 | NHP | Valdes,R | Demoted to reserve roster | | | Before |
| 7/11/2012 | TOR | Karstens | Promoted to active roster | | | Before |
| 7/11/2012 | TOR | Kearns | Promoted to active roster | | | Before |
| 7/11/2012 | TOR | Lewis,C | Demoted to reserve roster | | | Before |
| 7/11/2012 | TOR | Locke | Demoted to reserve roster | | | Before |
| 7/11/2012 | TOR | Schumaker | Demoted to reserve roster | | | Before |
| 7/11/2012 | TOR | Stammen | Activated from disabled list | | | Before |
| 7/11/2012 | WTB | Blackburn | Promoted to active roster | | | Before |
| 7/11/2012 | WTB | Hechavarria | Promoted to active roster | | | Before |
| 7/11/2012 | WTB | Hudson,O | Promoted to active roster | | | Before |
| 7/11/2012 | WTB | Treanor | Promoted to active roster | | | Before |
| 7/11/2012 | WTB | Wheeler,R | Promoted to active roster | | | Before |
| 7/13/2012 | WTB | Parmelee | Acquired via trade | BOX | | After |
| 7/14/2012 | TOR | Fien | Demoted to reserve roster | | | Before |
| 7/14/2012 | TOR | Wright,W | Promoted to active roster | | | Before |
| 7/14/2012 | WCM | Jepsen | Promoted to active roster | | | Before |
| 7/14/2012 | WCM | Markakis | Activated from disabled list | | | Before |
| 7/16/2012 | MON | Pacheco | Acquired via trade | CLE | | After |
| 7/16/2012 | MON | Podsednik | Traded away | CLE | | After |
| 7/16/2012 | MON | Putz | Acquired via trade | CLE | | After |
| 7/16/2012 | TOR | Barton | Traded away | CLE | | After |
| 7/16/2012 | TOR | Lombardozzi | Acquired via trade | CLE | | After |
| 7/16/2012 | TOR | Volstad | Acquired via trade | CLE | | After |
| 7/16/2012 | TOR | Wright,W | Traded away | CLE | | After |
| 7/17/2012 | AVA | Kinney | Demoted to reserve roster | | | Before |
| 7/17/2012 | AVA | Price | Activated from disabled list | | | Before |
| 7/17/2012 | DEG | Bell,H | Promoted to active roster | | | Before |
| 7/17/2012 | DEG | Mazzaro | Promoted to active roster | | | Before |
| 7/17/2012 | DEG | Peralta,W | Demoted to reserve roster | | | Before |
| 7/17/2012 | DEG | Santana,E | Placed on disabled list | | 7/17/2012 | Before |
| 7/17/2012 | MON | Berkman | Demoted to reserve roster | | | Before |
| 7/17/2012 | MON | Ramirez,R | Demoted to reserve roster | | | Before |
| 7/17/2012 | TOR | Fien | Promoted to active roster | | | Before |
| 7/17/2012 | TOR | Karstens | Demoted to reserve roster | | | Before |
| 7/17/2012 | TOR | Lewis,C | Promoted to active roster | | | Before |
| 7/17/2012 | TOR | Lombardozzi | Demoted to reserve roster | | | Before |
| 7/17/2012 | TOR | Volstad | Demoted to reserve roster | | | Before |
| 7/17/2012 | TOR | Volstad | Promoted to active roster | | | Before |
| 7/17/2012 | WTB | Arias | Placed on disabled list | | 7/13/2012 | Before |
| 7/17/2012 | WTB | Niese | Activated from disabled list | | | Before |
| 7/17/2012 | WTB | Paul | Demoted to reserve roster | | | Before |
| 7/19/2012 | MON | Lee,Cl | Acquired via trade | WTB | | After |
| 7/19/2012 | MON | Lowe,D | Traded away | WTB | | After |
| 7/19/2012 | MON | Richards | Traded away | WTB | | After |
| 7/19/2012 | WTB | Lee,Cl | Traded away | MON | | After |
| 7/19/2012 | WTB | Lowe,D | Acquired via trade | MON | | After |
| 7/19/2012 | WTB | Richards | Acquired via trade | MON | | After |
| 7/20/2012 | DSP | Berry | Demoted to reserve roster | | | Before |
| 7/20/2012 | DSP | McDonald,Jo | Promoted to active roster | | | Before |
| 7/20/2012 | DSP | Ogando | Demoted to reserve roster | | | Before |
| 7/20/2012 | DSP | Reimold | Promoted to active roster | | | Before |
| 7/20/2012 | MON | Lee,Cl | Placed on disabled list | | 7/17/2012 | Before |
| 7/20/2012 | WTB | Lowe,D | Promoted to active roster | | | Before |
| 7/20/2012 | WTB | Parmelee | Promoted to active roster | | | Before |
| 7/20/2012 | WTB | Richards | Promoted to active roster | | | Before |
| 7/22/2012 | DEG | Ryan | Traded away | DUR | | After |
| 7/22/2012 | PEA | Brantley | Acquired via trade | TOR | | After |
| 7/22/2012 | PEA | Colvin | Traded away | TOR | | After |
| 7/22/2012 | TOR | Brantley | Traded away | PEA | | After |
| 7/22/2012 | TOR | Colvin | Acquired via trade | PEA | | After |
| 7/23/2012 | DEG | Santiago,R | Promoted to active roster | | | Before |
| 7/23/2012 | PEA | Andino | Promoted to active roster | | | Before |
| 7/23/2012 | PEA | Horst | Demoted to reserve roster | | | Before |
| 7/23/2012 | PEA | Pedroia | Placed on disabled list | | 7/23/2012 | Before |
| 7/23/2012 | PEA | Reed | Promoted to active roster | | | Before |
| 7/25/2012 | PAW | Blevins | Traded away | CRB | | After |
| 7/25/2012 | PAW | Cardenas | Acquired via trade | MAN | | After |
| 7/25/2012 | PAW | Choate,R | Acquired via trade | CRB | | After |
| 7/25/2012 | PAW | Corporan | Traded away | CRB | | After |
| 7/25/2012 | PAW | Guerra | Acquired via trade | MAN | | After |
| 7/25/2012 | PAW | Johnson,E | Traded away | CRB | | After |
| 7/25/2012 | PAW | Leroux | Acquired via trade | CRB | | After |
| 7/25/2012 | PAW | Miller,A | Acquired via trade | MAN | | After |
| 7/25/2012 | PAW | Paredes | Acquired via trade | MAN | | After |
| 7/25/2012 | PAW | Schlereth | Acquired via trade | MAN | | After |
| 7/25/2012 | PAW | Turner,Ju | Acquired via trade | CRB | | After |
| 7/25/2012 | PAW | Wells,R | Acquired via trade | MAN | | After |
| 7/25/2012 | PAW | Wilson,Bo | Acquired via trade | CRB | | After |
| 7/25/2012 | PAW | Zito | Acquired via trade | MAN | | After |
| 7/25/2012 | PEA | Callaspo | Traded away | PBC | | After |
| 7/25/2012 | PEA | Hudson,T | Traded away | CGS | | After |
| 7/25/2012 | PEA | Humber | Acquired via trade | CGS | | After |
| 7/25/2012 | PEA | Johnson,Ro | Acquired via trade | CGS | | After |
| 7/25/2012 | PEA | Raburn | Acquired via trade | CGS | | After |
| 7/25/2012 | PEA | Rolen | Acquired via trade | CGS | | After |
| 7/25/2012 | PEA | Schafer,L | Acquired via trade | PBC | | After |
| 7/26/2012 | AVA | Fontenot | Demoted to reserve roster | | | Before |
| 7/26/2012 | AVA | Storey | Promoted to active roster | | | Before |
| 7/26/2012 | DSP | Adams,Mi | Promoted to active roster | | | Before |
| 7/26/2012 | DSP | Hanrahan | Promoted to active roster | | | Before |
| 7/26/2012 | DSP | Reimold | Demoted to reserve roster | | | Before |
| 7/26/2012 | DSP | Rodriguez,H | Demoted to reserve roster | | | Before |
| 7/26/2012 | MON | Middlebrooks | Demoted to reserve roster | | | Before |
| 7/26/2012 | MON | Rutledge | Promoted to active roster | | | Before |
| 7/26/2012 | PEA | Rolen | Promoted to active roster | | | Before |
| 7/26/2012 | PEA | Swarzak | Promoted to active roster | | | Before |
| 7/26/2012 | TOR | Fien | Demoted to reserve roster | | | Before |
| 7/26/2012 | TOR | Karstens | Promoted to active roster | | | Before |
| 7/26/2012 | TOR | Lewis,C | Demoted to reserve roster | | | Before |
| 7/26/2012 | TOR | Volstad | Promoted to active roster | | | Before |
| 7/29/2012 | DEG | Hernandez,R | Promoted to active roster | | | Before |
| 7/29/2012 | DEG | Olivo | Placed on disabled list | | 7/28/2012 | Before |
| 7/29/2012 | DSP | Ogando | Promoted to active roster | | | Before |
| 7/29/2012 | DSP | Wood,T | Placed on disabled list | | 7/28/2012 | Before |
| 7/29/2012 | NHP | Bass | Promoted to active roster | | | Before |
| 7/29/2012 | NHP | Gonzalez,Mig | Placed on disabled list | | 7/29/2012 | Before |
| 8/1/2012 | DSP | Berry | Promoted to active roster | | | Before |
| 8/1/2012 | DSP | McDonald,Jo | Demoted to reserve roster | | | Before |
| 8/1/2012 | DSP | Pearce,S | Demoted to reserve roster | | | Before |
| 8/1/2012 | DSP | Reimold | Promoted to active roster | | | Before |
| 8/1/2012 | TOR | Galvis | Demoted to reserve roster | | | Before |
| 8/1/2012 | TOR | Galvis | Promoted to active roster | | | Before |
| 8/1/2012 | TOR | Kearns | Demoted to reserve roster | | | Before |
| 8/1/2012 | TOR | Locke | Promoted to active roster | | | Before |
| 8/1/2012 | TOR | Lombardozzi | Promoted to active roster | | | Before |
| 8/1/2012 | TOR | Tillman | Demoted to reserve roster | | | Before |
| 8/4/2012 | MON | Berkman | Promoted to active roster | | | Before |
| 8/4/2012 | MON | Quentin | Demoted to reserve roster | | | Before |
| 8/4/2012 | NHP | Beavan | Promoted to active roster | | | Before |
| 8/4/2012 | NHP | Garcia,A | Demoted to reserve roster | | | Before |
| 8/4/2012 | NHP | Garcia,A | Promoted to active roster | | | Before |
| 8/4/2012 | NHP | Harvey | Demoted to reserve roster | | | Before |
| 8/4/2012 | PEA | Humber | Promoted to active roster | | | Before |
| 8/4/2012 | PEA | Norberto | Demoted to reserve roster | | | Before |
| 8/4/2012 | WCM | Henderson | Demoted to reserve roster | | | Before |
| 8/4/2012 | WCM | Kelley,S | Promoted to active roster | | | Before |
| 8/4/2012 | WCM | Morrow | Placed on disabled list | | 7/15/2012 | Before |
| 8/4/2012 | WCM | Mortensen | Promoted to active roster | | | Before |
| 8/7/2012 | MON | McAllister | Promoted to active roster | | | Before |
| 8/7/2012 | NHP | Garcia,A | Promoted to active roster | | | Before |
| 8/7/2012 | NHP | Pollock | Demoted to reserve roster | | | Before |
| 8/7/2012 | PAW | Hannahan | Demoted to reserve roster | | | Before |
| 8/7/2012 | PAW | Jurrjens | Demoted to reserve roster | | | Before |
| 8/7/2012 | PAW | Turner,Ju | Promoted to active roster | | | Before |
| 8/7/2012 | TOR | Kearns | Promoted to active roster | | | Before |
| 8/7/2012 | TOR | Plouffe | Placed on disabled list | | 8/7/2012 | Before |
| 8/7/2012 | WCM | Baxter | Demoted to reserve roster | | | Before |
| 8/10/2012 | DSP | Cabrera,Ev | Placed on disabled list | | 8/10/2012 | Before |
| 8/10/2012 | DSP | Drew,S | Promoted to active roster | | | Before |
| 8/10/2012 | NHP | Harvey | Promoted to active roster | | | Before |
| 8/10/2012 | NHP | Kirkman | Demoted to reserve roster | | | Before |
| 8/10/2012 | WTB | Arias | Activated from disabled list | | | Before |
| 8/10/2012 | WTB | Treanor | Demoted to reserve roster | | | Before |
| 8/13/2012 | DSP | Hellickson | Demoted to reserve roster | | | Before |
| 8/13/2012 | DSP | Wood,T | Activated from disabled list | | | Before |
| 8/13/2012 | TOR | Lowrie | Placed on disabled list | | 8/13/2012 | Before |
| 8/13/2012 | TOR | Schumaker | Promoted to active roster | | | Before |
| 8/16/2012 | AVA | Elbert | Demoted to reserve roster | | | Before |
| 8/16/2012 | AVA | Kalish | Promoted to active roster | | | Before |
| 8/16/2012 | AVA | Kinney | Promoted to active roster | | | Before |
| 8/16/2012 | AVA | Tulowitzki | Placed on disabled list | | 8/15/2012 | Before |
| 8/16/2012 | NHP | Beavan | Demoted to reserve roster | | | Before |
| 8/16/2012 | NHP | Beavan | Promoted to active roster | | | Before |
| 8/16/2012 | NHP | Gonzalez,Mig | Activated from disabled list | | | Before |
| 8/16/2012 | NHP | Harvey | Demoted to reserve roster | | | Before |
| 8/16/2012 | PEA | Andino | Demoted to reserve roster | | | Before |
| 8/16/2012 | PEA | Pedroia | Activated from disabled list | | | Before |
| 8/16/2012 | TOR | Lewis,C | Promoted to active roster | | | Before |
| 8/16/2012 | TOR | Volstad | Demoted to reserve roster | | | Before |
| 8/19/2012 | NHP | Beavan | Demoted to reserve roster | | | Before |
| 8/19/2012 | NHP | Smoak | Promoted to active roster | | | Before |
| 8/19/2012 | PAW | Blackmon | Demoted to reserve roster | | | Before |
| 8/19/2012 | PAW | Cardenas | Promoted to active roster | | | Before |
| 8/19/2012 | PAW | Choate,R | Promoted to active roster | | | Before |
| 8/19/2012 | PAW | Dobbs | Demoted to reserve roster | | | Before |
| 8/19/2012 | PAW | Green,Ta | Promoted to active roster | | | Before |
| 8/19/2012 | PAW | Paredes | Promoted to active roster | | | Before |
| 8/22/2012 | NHP | Gonzalez,Mig | Demoted to reserve roster | | | Before |
| 8/22/2012 | NHP | Harvey | Promoted to active roster | | | Before |
| 8/22/2012 | TOR | Fien | Promoted to active roster | | | Before |
| 8/22/2012 | TOR | Karstens | Demoted to reserve roster | | | Before |
| 8/22/2012 | TOR | Locke | Demoted to reserve roster | | | Before |
| 8/22/2012 | TOR | Tillman | Promoted to active roster | | | Before |
| 8/25/2012 | DSP | Hellickson | Promoted to active roster | | | Before |
| 8/25/2012 | DSP | LeBlanc | Demoted to reserve roster | | | Before |
| 8/25/2012 | NHP | Gonzalez,Mig | Promoted to active roster | | | Before |
| 8/25/2012 | NHP | Harvey | Demoted to reserve roster | | | Before |
| 8/28/2012 | BBK | Eaton | Promoted to active roster | | | Before |
| 8/28/2012 | BBK | Perez,S | Demoted to reserve roster | | | Before |
| 8/28/2012 | DSP | Cabrera,Ev | Activated from disabled list | | | Before |
| 8/28/2012 | DSP | Leake | Demoted to reserve roster | | | Before |
| 8/28/2012 | PAC | Lowe,M | Demoted to reserve roster | | | Before |
| 8/28/2012 | PAW | Bard | Demoted to reserve roster | | | Before |
| 8/28/2012 | PAW | Dunn,M | Demoted to reserve roster | | | Before |
| 8/28/2012 | PAW | Theriot | Demoted to reserve roster | | | Before |
| 8/28/2012 | PAW | Young,CB | Demoted to reserve roster | | | Before |
| 8/28/2012 | WCM | Byrdak | Demoted to reserve roster | | | Before |
| 8/28/2012 | WCM | Correia | Promoted to active roster | | | Before |
| 8/28/2012 | WCM | Feldman | Promoted to active roster | | | Before |
| 8/28/2012 | WCM | Laird,G | Demoted to reserve roster | | | Before |
| 8/28/2012 | WCM | Morrow | Activated from disabled list | | | Before |
| 8/28/2012 | WCM | Wallace | Demoted to reserve roster | | | Before |
| 8/28/2012 | WTB | Dotel | Demoted to reserve roster | | | Before |
| 8/28/2012 | WTB | Treanor | Promoted to active roster | | | Before |
| 8/31/2012 | DEG | Hernandez,R | Demoted to reserve roster | | | Before |
| 8/31/2012 | DEG | Keuchel | Demoted to reserve roster | | | Before |
| 8/31/2012 | DEG | Olivo | Activated from disabled list | | | Before |
| 8/31/2012 | DEG | Oswalt | Demoted to reserve roster | | | Before |
| 8/31/2012 | DEG | Santana,E | Activated from disabled list | | | Before |
| 8/31/2012 | DEG | Sheets | Promoted to active roster | | | Before |
| 8/31/2012 | NHP | Gonzalez,Mig | Demoted to reserve roster | | | Before |
| 8/31/2012 | NHP | Harvey | Promoted to active roster | | | Before |
| 8/31/2012 | PEA | Andino | Promoted to active roster | | | Before |
| 8/31/2012 | PEA | Polanco | Demoted to reserve roster | | | Before |
| 8/31/2012 | TOR | Fien | Demoted to reserve roster | | | Before |
| 8/31/2012 | TOR | Locke | Promoted to active roster | | | Before |
| 9/3/2012 | AVA | Kinney | Demoted to reserve roster | | | Before |
| 9/3/2012 | AVA | Ondrusek | Promoted to active roster | | | Before |
| 9/3/2012 | DSP | Adams,Mi | Demoted to reserve roster | | | Before |
| 9/3/2012 | DSP | Drew,S | Demoted to reserve roster | | | Before |
| 9/3/2012 | DSP | Leake | Promoted to active roster | | | Before |
| 9/3/2012 | DSP | Pearce,S | Promoted to active roster | | | Before |
| 9/3/2012 | PAW | Leroux | Promoted to active roster | | | Before |
| 9/3/2012 | PAW | Lucroy | Demoted to reserve roster | | | Before |
| 9/3/2012 | PAW | Miller,A | Promoted to active roster | | | Before |
| 9/3/2012 | PAW | Phelps,C | Promoted to active roster | | | Before |
| 9/3/2012 | PAW | Wells,R | Promoted to active roster | | | Before |
| 9/3/2012 | WTB | Hechavarria | Demoted to reserve roster | | | Before |
| 9/6/2012 | DSP | Drew,S | Promoted to active roster | | | Before |
| 9/6/2012 | DSP | Herrera | Demoted to reserve roster | | | Before |
| 9/6/2012 | DSP | McDonald,Jo | Demoted to reserve roster | | | Before |
| 9/6/2012 | DSP | McDonald,Jo | Promoted to active roster | | | Before |
| 9/6/2012 | DSP | Rodriguez,H | Promoted to active roster | | | Before |
| 9/6/2012 | DSP | Valbuena | Demoted to reserve roster | | | Before |
| 9/6/2012 | MON | Doubront | Promoted to active roster | | | Before |
| 9/6/2012 | MON | Milone | Placed on disabled list | | 9/6/2012 | Before |
| 9/6/2012 | PAC | Carpenter,DL | Promoted to active roster | | | Before |
| 9/6/2012 | PAC | Grandal | Demoted to reserve roster | | | Before |
| 9/6/2012 | PAC | Torrealba,Y | Promoted to active roster | | | Before |
| 9/9/2012 | NHP | Gonzalez,Mig | Promoted to active roster | | | Before |
| 9/9/2012 | NHP | Harvey | Demoted to reserve roster | | | Before |
| 9/12/2012 | BBK | Iwakuma | Demoted to reserve roster | | | Before |
| 9/12/2012 | BBK | Thornburg | Promoted to active roster | | | Before |
| 9/12/2012 | DEG | Kelly,J | Demoted to reserve roster | | | Before |
| 9/12/2012 | DEG | Keuchel | Promoted to active roster | | | Before |
| 9/12/2012 | NHP | Bass | Placed on disabled list | | 9/10/2012 | Before |
| 9/12/2012 | NHP | Beavan | Promoted to active roster | | | Before |
| 9/12/2012 | NHP | Gonzalez,Mig | Demoted to reserve roster | | | Before |
| 9/12/2012 | NHP | Hammel | Demoted to reserve roster | | | Before |
| 9/12/2012 | NHP | Porcello | Promoted to active roster | | | Before |
| 9/12/2012 | NHP | Valdes,R | Promoted to active roster | | | Before |
| 9/12/2012 | PAW | Cardenas | Demoted to reserve roster | | | Before |
| 9/12/2012 | PAW | Danks,JC | Demoted to reserve roster | | | Before |
| 9/12/2012 | PAW | Santana | Demoted to reserve roster | | | Before |
| 9/12/2012 | PAW | Turner,Ju | Demoted to reserve roster | | | Before |
| 9/12/2012 | TOR | Cueto | Demoted to reserve roster | | | Before |
| 9/12/2012 | TOR | Ellis,AJ | Demoted to reserve roster | | | Before |
| 9/12/2012 | TOR | Fien | Promoted to active roster | | | Before |
| 9/12/2012 | TOR | Karstens | Promoted to active roster | | | Before |
| 9/12/2012 | TOR | Lewis,C | Demoted to reserve roster | | | Before |
| 9/12/2012 | TOR | Norris,D | Promoted to active roster | | | Before |
| 9/12/2012 | TOR | Tillman | Demoted to reserve roster | | | Before |
| 9/12/2012 | TOR | Volstad | Promoted to active roster | | | Before |
| 9/12/2012 | WCM | Santiago,H | Demoted to reserve roster | | | Before |
| 9/12/2012 | WCM | Ziegler | Demoted to reserve roster | | | Before |
| 9/15/2012 | AVA | Gomez,J | Promoted to active roster | | | Before |
| 9/15/2012 | AVA | Patton | Demoted to reserve roster | | | Before |
| 9/15/2012 | DSP | Corbin | Demoted to reserve roster | | | Before |
| 9/15/2012 | DSP | LeBlanc | Promoted to active roster | | | Before |
| 9/15/2012 | NHP | Drabek | Promoted to active roster | | | Before |
| 9/15/2012 | NHP | Valdes,R | Demoted to reserve roster | | | Before |
| 9/15/2012 | WCM | Arencibia | Placed on disabled list | | 8/30/2012 | Before |
| 9/15/2012 | WCM | Baker,Jo | Promoted to active roster | | | Before |
| 9/15/2012 | WCM | Cowgill | Promoted to active roster | | | Before |
| 9/15/2012 | WCM | Simon | Promoted to active roster | | | Before |
| 9/15/2012 | WCM | Thole | Promoted to active roster | | | Before |
| 9/15/2012 | WCM | Watson | Demoted to reserve roster | | | Before |
| 9/15/2012 | WCM | Wise,D | Promoted to active roster | | | Before |
| 9/18/2012 | DSP | Hayes | Promoted to active roster | | | Before |
| 9/18/2012 | DSP | Hellickson | Demoted to reserve roster | | | Before |
| 9/18/2012 | DSP | McDonald,Jo | Promoted to active roster | | | Before |
| 9/18/2012 | DSP | Ross,D | Demoted to reserve roster | | | Before |
| 9/18/2012 | DSP | Valbuena | Promoted to active roster | | | Before |
| 9/18/2012 | DSP | Wood,T | Demoted to reserve roster | | | Before |
| 9/18/2012 | WTB | Blackley,T | Demoted to reserve roster | | | Before |
| 9/18/2012 | WTB | Wheeler,R | Demoted to reserve roster | | | Before |
| 2/26/2013 | PEA | Bourn | Traded away | WTB | | After |
| 2/26/2013 | PEA | Kubel | Acquired via trade | WTB | | After |
| 2/26/2013 | PEA | Melancon | Acquired via trade | WTB | | After |
| 2/26/2013 | PEA | Werth | Acquired via trade | WTB | | After |
| 2/26/2013 | WTB | Bourn | Acquired via trade | PEA | | After |
| 2/26/2013 | WTB | Kubel | Traded away | PEA | | After |
| 2/26/2013 | WTB | Melancon | Traded away | PEA | | After |
| 2/26/2013 | WTB | Werth | Traded away | PEA | | After |