| Transactions |
| Date | Team | Player | Type | OthTm | EffDate | When |
| 4/6/2020 | ACS | Madrigal | Acquired via trade | BB | | After |
| 4/6/2020 | SFR | Laureano | Promoted to active roster | | | Before |
| 4/10/2020 | PL | Anderson,N | Promoted to active roster | | | Before |
| 4/16/2020 | BC | Gott | Traded away | VD | | After |
| 4/16/2020 | BC | Kiermaier | Acquired via trade | VD | | After |
| 4/17/2020 | BC | Choi | Demoted to reserve roster | | | Before |
| 4/17/2020 | BC | Kiermaier | Promoted to active roster | | | Before |
| 4/17/2020 | SFR | Keller,B | Promoted to active roster | | | Before |
| 4/17/2020 | SFR | Laureano | Demoted to reserve roster | | | Before |
| 4/22/2020 | SFR | Keller,B | Demoted to reserve roster | | | Before |
| 4/22/2020 | SFR | Laureano | Promoted to active roster | | | Before |
| 4/25/2020 | BTB | Diaz,Ya | Demoted to reserve roster | | | Before |
| 4/25/2020 | BTB | Diaz,Ya | Promoted to active roster | | | Before |
| 4/29/2020 | PL | Bedrosian | Promoted to active roster | | | Before |
| 4/29/2020 | PL | Harper,R | Demoted to reserve roster | | | Before |
| 5/5/2020 | SFR | Keller,B | Promoted to active roster | | | Before |
| 5/5/2020 | SFR | Lamet | Demoted to reserve roster | | | Before |
| 5/6/2020 | BTB | Keuchel | Promoted to active roster | | | Before |
| 5/6/2020 | BTB | Stroman | Demoted to reserve roster | | | Before |
| 5/9/2020 | SFR | Alfaro | Promoted to active roster | | | Before |
| 5/9/2020 | SFR | Means | Demoted to reserve roster | | | Before |
| 5/10/2020 | BTB | Keuchel | Demoted to reserve roster | | | Before |
| 5/10/2020 | BTB | Stroman | Promoted to active roster | | | Before |
| 5/10/2020 | SFR | Means | Promoted to active roster | | | Before |
| 5/10/2020 | SFR | Stephenson | Demoted to reserve roster | | | Before |
| 5/12/2020 | PL | Clevinger | Acquired via trade | BB | | After |
| 5/12/2020 | PL | Lux | Traded away | BB | | After |
| 5/12/2020 | PL | Pearson | Traded away | BB | | After |
| 5/12/2020 | SFR | Alcantara,S | Acquired via trade | ShS | | After |
| 5/12/2020 | SFR | Rendon | Acquired via trade | ShS | | After |
| 5/12/2020 | SFR | Stanton | Traded away | ShS | | After |
| 5/12/2020 | SFR | Urshela | Traded away | ShS | | After |
| 5/13/2020 | PL | Bundy | Demoted to reserve roster | | | Before |
| 5/13/2020 | SFR | Alcantara,S | Demoted to reserve roster | | | Before |
| 5/14/2020 | SFR | Alcantara,S | Promoted to active roster | | | Before |
| 5/14/2020 | SFR | Darvish | Demoted to reserve roster | | | Before |
| 5/15/2020 | BTB | Jansen,K | Traded away | ShS | | After |
| 5/15/2020 | BTB | Senzel | Traded away | ShS | | After |
| 5/15/2020 | BTB | Urshela | Acquired via trade | ShS | | After |
| 5/16/2020 | BTB | Canning | Demoted to reserve roster | | | Before |
| 5/23/2020 | AH | Bundy | Acquired via trade | PL | | After |
| 5/23/2020 | AH | Gamel | Traded away | PL | | After |
| 5/23/2020 | AH | Hamels | Acquired via trade | PL | | After |
| 5/23/2020 | AH | Morton | Traded away | PL | | After |
| 5/23/2020 | AH | Vazquez,F | Traded away | PL | | After |
| 5/23/2020 | PL | Bundy | Traded away | AH | | After |
| 5/23/2020 | PL | Gamel | Acquired via trade | AH | | After |
| 5/23/2020 | PL | Hamels | Traded away | AH | | After |
| 5/23/2020 | PL | Morton | Acquired via trade | AH | | After |
| 5/23/2020 | PL | Vazquez,F | Acquired via trade | AH | | After |
| 5/24/2020 | AH | Bundy | Promoted to active roster | | | Before |
| 5/24/2020 | PL | Bedrosian | Demoted to reserve roster | | | Before |
| 5/24/2020 | PL | Thornton | Signed | | | Before |
| 5/24/2020 | PL | Marisnick | Acquired via trade | ShS | | After |
| 5/24/2020 | PL | Richards,T | Traded away | ShS | | After |
| 5/24/2020 | SFR | Garcia,Y | Demoted to reserve roster | | | Before |
| 5/24/2020 | SFR | Stephenson | Promoted to active roster | | | Before |
| 5/26/2020 | PL | Bishop | Demoted to reserve roster | | | Before |
| 5/26/2020 | PL | Brantley | Demoted to reserve roster | | | Before |
| 5/26/2020 | PL | Thornton | Released | | | Before |
| 5/27/2020 | BTB | Fiers | Acquired via trade | ShS | | After |
| 5/27/2020 | BTB | Keuchel | Traded away | ShS | | After |
| 5/28/2020 | BTB | Fiers | Demoted to reserve roster | | | Before |
| 5/29/2020 | BTB | Fiers | Promoted to active roster | | | Before |
| 5/29/2020 | BTB | Ottavino | Demoted to reserve roster | | | Before |
| 5/30/2020 | SFR | Garcia,Y | Promoted to active roster | | | Before |
| 5/30/2020 | SFR | Stephenson | Demoted to reserve roster | | | Before |
| 6/3/2020 | BTB | Ottavino | Promoted to active roster | | | Before |
| 6/3/2020 | BTB | Paxton | Demoted to reserve roster | | | Before |
| 6/3/2020 | PL | Osuna,R | Acquired via trade | End | | After |
| 6/3/2020 | SFR | Petit | Demoted to reserve roster | | | Before |
| 6/3/2020 | SFR | Stephenson | Promoted to active roster | | | Before |
| 6/4/2020 | PL | Osuna,R | Promoted to active roster | | | Before |
| 6/4/2020 | PL | Young | Demoted to reserve roster | | | Before |
| 6/7/2020 | BTB | Ottavino | Demoted to reserve roster | | | Before |
| 6/7/2020 | BTB | Paxton | Promoted to active roster | | | Before |
| 6/7/2020 | PL | Brantley | Promoted to active roster | | | Before |
| 6/7/2020 | PL | Gurriel,L | Demoted to reserve roster | | | Before |
| 6/12/2020 | BTB | Ottavino | Promoted to active roster | | | Before |
| 6/12/2020 | BTB | Paxton | Demoted to reserve roster | | | Before |
| 6/14/2020 | AH | Garver | Traded away | PL | | After |
| 6/14/2020 | PL | Garver | Acquired via trade | AH | | After |
| 6/15/2020 | PL | Villar | Demoted to reserve roster | | | Before |
| 6/17/2020 | PL | Caratini | Demoted to reserve roster | | | Before |
| 6/17/2020 | PL | Winker | Promoted to active roster | | | Before |
| 6/17/2020 | SFR | Brennan | Promoted to active roster | | | Before |
| 6/17/2020 | SFR | Chirinos,R | Demoted to reserve roster | | | Before |
| 6/23/2020 | AH | Chapman,A | Traded away | BC | | After |
| 6/23/2020 | AH | Plesac | Acquired via trade | BC | | After |
| 6/23/2020 | BC | Chapman,A | Acquired via trade | AH | | After |
| 6/23/2020 | BC | Plesac | Traded away | AH | | After |
| 6/24/2020 | AH | Plesac | Promoted to active roster | | | Before |
| 6/24/2020 | BC | Giles | Demoted to reserve roster | | | Before |
| 6/24/2020 | SFR | Chirinos,R | Promoted to active roster | | | Before |
| 6/24/2020 | SFR | Laureano | Demoted to reserve roster | | | Before |
| 6/26/2020 | AH | Abreu,J | Traded away | BTB | | After |
| 6/26/2020 | AH | Canning | Acquired via trade | BTB | | After |
| 6/26/2020 | AH | Diaz,Ya | Acquired via trade | BTB | | After |
| 6/26/2020 | AH | Kintzler | Traded away | BTB | | After |
| 6/26/2020 | AH | Odorizzi | Traded away | BTB | | After |
| 6/26/2020 | BTB | Abreu,J | Acquired via trade | AH | | After |
| 6/26/2020 | BTB | Canning | Traded away | AH | | After |
| 6/26/2020 | BTB | Diaz,Ya | Traded away | AH | | After |
| 6/26/2020 | BTB | Kintzler | Acquired via trade | AH | | After |
| 6/26/2020 | BTB | Odorizzi | Acquired via trade | AH | | After |
| 6/27/2020 | AH | Canning | Promoted to active roster | | | Before |
| 6/27/2020 | AH | James | Promoted to active roster | | | Before |
| 6/27/2020 | BTB | Odorizzi | Demoted to reserve roster | | | Before |
| 6/27/2020 | BTB | Ottavino | Demoted to reserve roster | | | Before |
| 7/3/2020 | BTB | Fiers | Demoted to reserve roster | | | Before |
| 7/3/2020 | BTB | Odorizzi | Promoted to active roster | | | Before |
| 7/7/2020 | BTB | Fiers | Promoted to active roster | | | Before |
| 7/7/2020 | BTB | Odorizzi | Demoted to reserve roster | | | Before |
| 7/7/2020 | BTB | Paxton | Promoted to active roster | | | Before |
| 7/7/2020 | BTB | Stroman | Demoted to reserve roster | | | Before |
| 7/12/2020 | BTB | Paxton | Demoted to reserve roster | | | Before |
| 7/12/2020 | BTB | Stroman | Promoted to active roster | | | Before |
| 7/17/2020 | BTB | Baez,P | Acquired via trade | WN | | After |
| 7/17/2020 | BTB | Howard | Traded away | WN | | After |
| 7/17/2020 | BTB | Kieboom | Traded away | WN | | After |
| 7/17/2020 | BTB | Rogers,Ta | Acquired via trade | WN | | After |
| 7/17/2020 | BTB | Wittgren | Traded away | WN | | After |
| 7/17/2020 | PL | Benintendi | Acquired via trade | End | | After |
| 7/17/2020 | PL | Betts | Acquired via trade | WN | | After |
| 7/17/2020 | PL | Bogaerts | Traded away | WN | | After |
| 7/17/2020 | PL | Freeman,F | Acquired via trade | WN | | After |
| 7/17/2020 | PL | Gardner | Acquired via trade | WN | | After |
| 7/17/2020 | PL | Greinke | Acquired via trade | WN | | After |
| 7/17/2020 | PL | Rizzo | Traded away | End | | After |
| 7/17/2020 | PL | Semien | Acquired via trade | WN | | After |
| 7/17/2020 | PL | Urias,J | Acquired via trade | End | | After |
| 7/17/2020 | PL | Verlander | Traded away | WN | | After |
| 7/17/2020 | PL | Yelich | Traded away | WN | | After |
| 7/17/2020 | PL | Young | Traded away | End | | After |
| 7/17/2020 | SFR | Petit | Traded away | VD | | After |
| 7/17/2020 | WN | Baez,P | Traded away | BTB | | After |
| 7/17/2020 | WN | Betts | Traded away | PL | | After |
| 7/17/2020 | WN | Bogaerts | Acquired via trade | PL | | After |
| 7/17/2020 | WN | Freeman,F | Traded away | PL | | After |
| 7/17/2020 | WN | Gardner | Traded away | PL | | After |
| 7/17/2020 | WN | Greinke | Traded away | PL | | After |
| 7/17/2020 | WN | Howard | Acquired via trade | BTB | | After |
| 7/17/2020 | WN | Kieboom | Acquired via trade | BTB | | After |
| 7/17/2020 | WN | Rogers,Ta | Traded away | BTB | | After |
| 7/17/2020 | WN | Semien | Traded away | PL | | After |
| 7/17/2020 | WN | Verlander | Acquired via trade | PL | | After |
| 7/17/2020 | WN | Wittgren | Acquired via trade | BTB | | After |
| 7/17/2020 | WN | Yelich | Acquired via trade | PL | | After |
| 7/18/2020 | BTB | May,T | Demoted to reserve roster | | | Before |
| 7/18/2020 | PL | Benintendi | Demoted to reserve roster | | | Before |
| 7/18/2020 | PL | Brantley | Demoted to reserve roster | | | Before |
| 7/18/2020 | PL | Gurriel,L | Promoted to active roster | | | Before |
| 7/18/2020 | PL | Marisnick | Demoted to reserve roster | | | Before |
| 7/18/2020 | PL | Ramirez,No | Demoted to reserve roster | | | Before |
| 7/18/2020 | PL | Urias,J | Promoted to active roster | | | Before |
| 7/18/2020 | WN | Carrasco | Promoted to active roster | | | Before |
| 7/18/2020 | WN | Hosmer | Promoted to active roster | | | Before |
| 7/18/2020 | WN | Segura | Promoted to active roster | | | Before |
| 7/19/2020 | PL | Brantley | Traded away | End | | After |
| 7/19/2020 | PL | Grisham | Acquired via trade | End | | After |
| 7/20/2020 | PL | Bass | Acquired via trade | BB | | After |
| 7/20/2020 | PL | Bedrosian | Traded away | BB | | After |
| 7/21/2020 | BTB | Fiers | Demoted to reserve roster | | | Before |
| 7/21/2020 | BTB | Odorizzi | Promoted to active roster | | | Before |
| 7/21/2020 | PL | Anderson,N | Demoted to reserve roster | | | Before |
| 7/26/2020 | WN | Robles,V | Acquired via trade | End | | After |
| 7/26/2020 | WN | Verlander | Traded away | End | | After |
| 7/29/2020 | ACS | Fried | Acquired via trade | VD | | After |
| 7/29/2020 | ACS | Marquez | Traded away | VD | | After |
| 7/29/2020 | ACS | Voth | Traded away | VD | | After |
| 8/2/2020 | SFR | Brennan | Demoted to reserve roster | | | Before |
| 8/2/2020 | SFR | Laureano | Promoted to active roster | | | Before |
| 8/20/2020 | SFR | Castillo,L | Demoted to reserve roster | | | Before |
| 8/20/2020 | SFR | Darvish | Promoted to active roster | | | Before |
| 8/21/2020 | SFR | Castillo,L | Promoted to active roster | | | Before |
| 8/21/2020 | SFR | Darvish | Demoted to reserve roster | | | Before |
| 9/9/2020 | BTB | Fiers | Promoted to active roster | | | Before |
| 9/9/2020 | BTB | Stroman | Demoted to reserve roster | | | Before |
| 9/11/2020 | BTB | Fiers | Demoted to reserve roster | | | Before |
| 9/11/2020 | BTB | Paxton | Promoted to active roster | | | Before |
| 9/12/2020 | BTB | Ottavino | Promoted to active roster | | | Before |
| 9/12/2020 | BTB | Paxton | Demoted to reserve roster | | | Before |
| 9/12/2020 | BTB | Rogers,Ta | Demoted to reserve roster | | | Before |
| 9/12/2020 | BTB | Stroman | Promoted to active roster | | | Before |
| 9/24/2020 | BTB | Ottavino | Demoted to reserve roster | | | Before |
| 9/24/2020 | BTB | Rogers,Ta | Promoted to active roster | | | Before |