| Transactions |
| Date | Team | Player | Type | OthTm | EffDate | When |
| 4/1/2019 | SF | Anderson,S | Demoted to reserve roster | | | Before |
| 4/1/2019 | SF | Astudillo | Promoted to active roster | | | Before |
| 4/1/2019 | SF | Choi | Promoted to active roster | | | Before |
| 4/1/2019 | SF | Desmond | Promoted to active roster | | | Before |
| 4/1/2019 | SF | Font | Demoted to reserve roster | | | Before |
| 4/1/2019 | SF | Gyorko | Promoted to active roster | | | Before |
| 4/1/2019 | SF | Hanson | Promoted to active roster | | | Before |
| 4/1/2019 | SF | Harrison,M | Demoted to reserve roster | | | Before |
| 4/1/2019 | SF | Heredia | Demoted to reserve roster | | | Before |
| 4/1/2019 | SF | Kendrick | Promoted to active roster | | | Before |
| 4/1/2019 | SF | Kieboom,C | Demoted to reserve roster | | | Before |
| 4/1/2019 | SF | Rooker | Demoted to reserve roster | | | Before |
| 4/1/2019 | SF | Sanchez,An | Promoted to active roster | | | Before |
| 4/1/2019 | SF | Sanchez,Y | Demoted to reserve roster | | | Before |
| 4/1/2019 | SF | Suarez,A | Demoted to reserve roster | | | Before |
| 4/1/2019 | SF | Taylor,Cu | Promoted to active roster | | | Before |
| 4/5/2019 | Atl | Diplan | Released | | | Before |
| 4/5/2019 | Atl | Weber | Signed | | | Before |
| 4/5/2019 | Cin | Ferguson,D | Signed | | | Before |
| 4/5/2019 | Cin | Ferguson,D | Promoted to active roster | | | Before |
| 4/5/2019 | Cin | Law,D | Signed | | | Before |
| 4/5/2019 | Cin | Law,D | Promoted to active roster | | | Before |
| 4/5/2019 | Cin | Peraza | Demoted to reserve roster | | | Before |
| 4/5/2019 | Cin | Ramos,H | Released | | | Before |
| 4/5/2019 | Cin | Reed,Ad | Released | | | Before |
| 4/5/2019 | Cin | Vizcaino | Demoted to reserve roster | | | Before |
| 4/5/2019 | Phi | Franklin | Promoted to active roster | | | Before |
| 4/5/2019 | Phi | Garcia,E | Demoted to reserve roster | | | Before |
| 4/5/2019 | Phi | German | Promoted to active roster | | | Before |
| 4/5/2019 | Phi | Gregerson | Demoted to reserve roster | | | Before |
| 4/5/2019 | Phi | Happ,I | Promoted to active roster | | | Before |
| 4/5/2019 | Phi | Heaney | Demoted to reserve roster | | | Before |
| 4/5/2019 | Phi | Hernandez,K | Promoted to active roster | | | Before |
| 4/5/2019 | Phi | Hunter | Demoted to reserve roster | | | Before |
| 4/5/2019 | Phi | Irvin | Demoted to reserve roster | | | Before |
| 4/5/2019 | Phi | Kepler | Promoted to active roster | | | Before |
| 4/5/2019 | Phi | McCann,J | Promoted to active roster | | | Before |
| 4/5/2019 | Phi | Minter | Promoted to active roster | | | Before |
| 4/5/2019 | Phi | Moniak | Demoted to reserve roster | | | Before |
| 4/5/2019 | Phi | Neris | Promoted to active roster | | | Before |
| 4/5/2019 | Phi | Parra,G | Demoted to reserve roster | | | Before |
| 4/5/2019 | Phi | Quinn,R | Demoted to reserve roster | | | Before |
| 4/5/2019 | Pit | Cabrera,Me | Released | | | Before |
| 4/5/2019 | Pit | Carle | Demoted to reserve roster | | | Before |
| 4/5/2019 | Pit | Cedeno | Demoted to reserve roster | | | Before |
| 4/5/2019 | Pit | Cessa | Signed | | | Before |
| 4/5/2019 | Pit | Cobb | Released | | | Before |
| 4/5/2019 | Pit | Harvey,M | Promoted to active roster | | | Before |
| 4/5/2019 | Pit | Kittredge | Released | | | Before |
| 4/5/2019 | Pit | Leyba | Signed | | | Before |
| 4/5/2019 | Pit | Means | Signed | | | Before |
| 4/5/2019 | Pit | Moreland | Promoted to active roster | | | Before |
| 4/5/2019 | Pit | Samardzija | Promoted to active roster | | | Before |
| 4/5/2019 | Pit | Santana,Er | Demoted to reserve roster | | | Before |
| 4/5/2019 | Pit | Santana,Er | Promoted to active roster | | | Before |
| 4/5/2019 | Pit | Sosa | Signed | | | Before |
| 4/5/2019 | Pit | Weber | Released | | | Before |
| 4/5/2019 | Pit | Zimmermann,J | Demoted to reserve roster | | | Before |
| 4/5/2019 | Pit | Zimmermann,J | Promoted to active roster | | | Before |
| 4/5/2019 | Pit | Zimmermann,J | Promoted to active roster | | | Before |
| 4/5/2019 | SD | Brach | Promoted to active roster | | | Before |
| 4/5/2019 | SD | d'Arnaud,T | Demoted to reserve roster | | | Before |
| 4/5/2019 | SD | Dunand | Demoted to reserve roster | | | Before |
| 4/5/2019 | SD | Fuentes,R | Demoted to reserve roster | | | Before |
| 4/5/2019 | SD | Fuentes,R | Promoted to active roster | | | Before |
| 4/5/2019 | SD | Hand | Promoted to active roster | | | Before |
| 4/5/2019 | SD | Heyward | Promoted to active roster | | | Before |
| 4/5/2019 | SD | Lopez,Jor | Demoted to reserve roster | | | Before |
| 4/5/2019 | SD | Martin,Cod | Demoted to reserve roster | | | Before |
| 4/5/2019 | SD | Miley | Demoted to reserve roster | | | Before |
| 4/5/2019 | SD | Nelson,Ji | Demoted to reserve roster | | | Before |
| 4/5/2019 | SD | Odorizzi | Promoted to active roster | | | Before |
| 4/5/2019 | SD | Pomeranz | Promoted to active roster | | | Before |
| 4/5/2019 | SD | Ponce | Demoted to reserve roster | | | Before |
| 4/5/2019 | SD | Puello | Promoted to active roster | | | Before |
| 4/5/2019 | SD | Rosenthal | Promoted to active roster | | | Before |
| 4/5/2019 | SD | Ross,R Jr. | Demoted to reserve roster | | | Before |
| 4/5/2019 | SD | Shields | Demoted to reserve roster | | | Before |
| 4/5/2019 | SD | Spangenberg | Promoted to active roster | | | Before |
| 4/5/2019 | SD | Varsho | Demoted to reserve roster | | | Before |
| 4/5/2019 | SD | Varsho | Promoted to active roster | | | Before |
| 4/5/2019 | SD | Yarbrough | Promoted to active roster | | | Before |
| 4/8/2019 | Atl | Miller,S | Demoted to reserve roster | | | Before |
| 4/8/2019 | Atl | Weber | Promoted to active roster | | | Before |
| 4/8/2019 | Pit | Andujar | Demoted to reserve roster | | | Before |
| 4/8/2019 | Pit | Lamb,Ja | Demoted to reserve roster | | | Before |
| 4/8/2019 | Pit | Means | Promoted to active roster | | | Before |
| 4/8/2019 | Pit | Sosa | Promoted to active roster | | | Before |
| 4/8/2019 | Pit | Stanton | Demoted to reserve roster | | | Before |
| 4/8/2019 | Pit | Thornton | Promoted to active roster | | | Before |
| 4/11/2019 | Pit | Edwards,C | Traded away | Tex | | After |
| 4/12/2019 | Ari | Barrera,T | Signed | | | Before |
| 4/12/2019 | ChN | Cole,T | Signed | | | Before |
| 4/12/2019 | ChN | Petricka | Released | | | Before |
| 4/12/2019 | Cin | Gonzalez,G | Promoted to active roster | | | Before |
| 4/12/2019 | Cin | Law,D | Demoted to reserve roster | | | Before |
| 4/12/2019 | Cin | Lorenzen | Demoted to reserve roster | | | Before |
| 4/12/2019 | Cin | Mills,A | Promoted to active roster | | | Before |
| 4/12/2019 | Cin | Vizcaino | Released | | | Before |
| 4/12/2019 | Pit | Cessa | Released | | | Before |
| 4/12/2019 | Pit | Cobb | Signed | | | Before |
| 4/12/2019 | Pit | Estevez,O | Promoted to active roster | | | Before |
| 4/12/2019 | Pit | Leyba | Promoted to active roster | | | Before |
| 4/12/2019 | Pit | Santana,Er | Released | | | Before |
| 4/12/2019 | SF | Webb,T | Signed | | | Before |
| 4/15/2019 | Atl | Miller,S | Promoted to active roster | | | Before |
| 4/15/2019 | Atl | Shepherd | Demoted to reserve roster | | | Before |
| 4/15/2019 | Cin | Armstrong | Promoted to active roster | | | Before |
| 4/15/2019 | Cin | Ferguson,D | Demoted to reserve roster | | | Before |
| 4/15/2019 | Cin | Loup | Demoted to reserve roster | | | Before |
| 4/15/2019 | Cin | Mills,A | Demoted to reserve roster | | | Before |
| 4/15/2019 | Cin | Peraza | Promoted to active roster | | | Before |
| 4/15/2019 | Cin | Zamora | Promoted to active roster | | | Before |
| 4/15/2019 | Mil | Cease | Demoted to reserve roster | | | Before |
| 4/15/2019 | Mil | Cease | Promoted to active roster | | | Before |
| 4/15/2019 | Mil | Chatham | Promoted to active roster | | | Before |
| 4/15/2019 | Mil | Holt | Demoted to reserve roster | | | Before |
| 4/15/2019 | Mil | Johnson,B | Demoted to reserve roster | | | Before |
| 4/15/2019 | Mil | Tepera | Promoted to active roster | | | Before |
| 4/15/2019 | Pit | Carle | Released | | | Before |
| 4/15/2019 | Pit | Howard,B | Promoted to active roster | | | Before |
| 4/15/2019 | Pit | LeBlanc,W | Demoted to reserve roster | | | Before |
| 4/19/2019 | Atl | Jeffress | Promoted to active roster | | | Before |
| 4/19/2019 | Atl | Triggs | Demoted to reserve roster | | | Before |
| 4/19/2019 | Pit | Howard,B | Demoted to reserve roster | | | Before |
| 4/19/2019 | Was | Cave | Signed | | | Before |
| 4/22/2019 | ChN | Burke | Demoted to reserve roster | | | Before |
| 4/22/2019 | ChN | Chirinos,Y | Promoted to active roster | | | Before |
| 4/22/2019 | ChN | Cole,T | Promoted to active roster | | | Before |
| 4/22/2019 | ChN | Hall,M | Demoted to reserve roster | | | Before |
| 4/22/2019 | Cin | Almora | Promoted to active roster | | | Before |
| 4/22/2019 | Cin | Quiroz | Demoted to reserve roster | | | Before |
| 4/25/2019 | Cin | Cervelli | Traded away | Phi | | After |
| 4/25/2019 | Cin | German | Acquired via trade | Phi | | After |
| 4/25/2019 | Cin | Givens | Traded away | Phi | | After |
| 4/25/2019 | Cin | Hamels | Traded away | Phi | | After |
| 4/25/2019 | Phi | Cervelli | Acquired via trade | Cin | | After |
| 4/25/2019 | Phi | German | Traded away | Cin | | After |
| 4/25/2019 | Phi | Givens | Acquired via trade | Cin | | After |
| 4/25/2019 | Phi | Hamels | Acquired via trade | Cin | | After |
| 4/26/2019 | Ari | Viloria | Released | | | Before |
| 4/26/2019 | Ari | Wong,Ke | Signed | | | Before |
| 4/26/2019 | Atl | Rhame | Released | | | Before |
| 4/26/2019 | Cin | Almora | Demoted to reserve roster | | | Before |
| 4/26/2019 | Cin | Ferguson,D | Promoted to active roster | | | Before |
| 4/26/2019 | Cin | German | Demoted to reserve roster | | | Before |
| 4/26/2019 | Cin | Harrison,Jos | Released | | | Before |
| 4/26/2019 | Cin | Law,D | Promoted to active roster | | | Before |
| 4/26/2019 | Cin | Lorenzen | Promoted to active roster | | | Before |
| 4/26/2019 | Cin | Plawecki | Promoted to active roster | | | Before |
| 4/26/2019 | Cin | Ramos,H | Signed | | | Before |
| 4/26/2019 | Cin | VanMeter | Signed | | | Before |
| 4/26/2019 | Col | Duggar | Promoted to active roster | | | Before |
| 4/26/2019 | Col | Frazier,C | Demoted to reserve roster | | | Before |
| 4/26/2019 | Phi | McCann,J | Demoted to reserve roster | | | Before |
| 4/26/2019 | Phi | Morgan,A | Demoted to reserve roster | | | Before |
| 4/26/2019 | Pit | Brubaker | Released | | | Before |
| 4/26/2019 | Pit | Cobb | Released | | | Before |
| 4/26/2019 | SF | Ross,T | Released | | | Before |
| 4/29/2019 | Ari | Barrera,T | Promoted to active roster | | | Before |
| 4/29/2019 | Ari | Foltynewicz | Promoted to active roster | | | Before |
| 4/29/2019 | Ari | Meadows | Demoted to reserve roster | | | Before |
| 4/29/2019 | Ari | Soroka | Promoted to active roster | | | Before |
| 4/29/2019 | Ari | Widener | Demoted to reserve roster | | | Before |
| 4/29/2019 | Atl | Gearrin | Demoted to reserve roster | | | Before |
| 4/29/2019 | Atl | Peterson,T | Promoted to active roster | | | Before |
| 4/29/2019 | ChN | Dean,A | Promoted to active roster | | | Before |
| 4/29/2019 | ChN | Pirela | Demoted to reserve roster | | | Before |
| 4/29/2019 | Col | Biddle | Demoted to reserve roster | | | Before |
| 4/29/2019 | Col | Swarzak | Promoted to active roster | | | Before |
| 4/29/2019 | Mia | Avilan | Promoted to active roster | | | Before |
| 4/29/2019 | Mia | Cozart,Z | Demoted to reserve roster | | | Before |
| 4/29/2019 | Mia | Drake | Promoted to active roster | | | Before |
| 4/29/2019 | Mia | Familia | Demoted to reserve roster | | | Before |
| 4/29/2019 | Pit | Oliva | Promoted to active roster | | | Before |
| 5/3/2019 | Pit | Hill,R | Promoted to active roster | | | Before |
| 5/3/2019 | Pit | Sosa | Demoted to reserve roster | | | Before |
| 5/5/2019 | Cin | Claudio | Traded away | Col | | After |
| 5/5/2019 | Cin | Diaz,Yu | Acquired via trade | Col | | After |
| 5/5/2019 | Cin | Kremer | Acquired via trade | Col | | After |
| 5/5/2019 | Cin | Reddick | Traded away | Col | | After |
| 5/5/2019 | Col | Claudio | Acquired via trade | Cin | | After |
| 5/5/2019 | Col | Diaz,Yu | Traded away | Cin | | After |
| 5/5/2019 | Col | Kremer | Traded away | Cin | | After |
| 5/5/2019 | Col | Reddick | Acquired via trade | Cin | | After |
| 5/5/2019 | Pit | Zimmermann,J | Demoted to reserve roster | | | Before |
| 5/6/2019 | Ari | Cumberland | Signed | | | Before |
| 5/6/2019 | Atl | Castillo,R | Released | | | Before |
| 5/6/2019 | Atl | Fraley | Signed | | | Before |
| 5/6/2019 | Atl | Peterson,T | Released | | | Before |
| 5/6/2019 | ChN | Cronenworth | Signed | | | Before |
| 5/6/2019 | ChN | Dickerson,A | Promoted to active roster | | | Before |
| 5/6/2019 | ChN | Hall,M | Promoted to active roster | | | Before |
| 5/6/2019 | ChN | Happ,J | Demoted to reserve roster | | | Before |
| 5/6/2019 | ChN | McCarthy,J | Released | | | Before |
| 5/6/2019 | ChN | Miller,Bri | Released | | | Before |
| 5/6/2019 | ChN | Reed,M | Demoted to reserve roster | | | Before |
| 5/6/2019 | Cin | Diaz,Yu | Demoted to reserve roster | | | Before |
| 5/6/2019 | Cin | Duda | Demoted to reserve roster | | | Before |
| 5/6/2019 | Cin | Duda | Promoted to active roster | | | Before |
| 5/6/2019 | Cin | Duda | Demoted to reserve roster | | | Before |
| 5/6/2019 | Cin | Mills,A | Promoted to active roster | | | Before |
| 5/6/2019 | Cin | Osuna,J | Promoted to active roster | | | Before |
| 5/6/2019 | Cin | Quiroz | Promoted to active roster | | | Before |
| 5/6/2019 | Cin | Ramos,H | Released | | | Before |
| 5/6/2019 | Cin | Whitlock | Signed | | | Before |
| 5/6/2019 | Col | Duplantier | Promoted to active roster | | | Before |
| 5/6/2019 | Col | Ferguson,C | Demoted to reserve roster | | | Before |
| 5/6/2019 | Col | Martin,Jas | Promoted to active roster | | | Before |
| 5/6/2019 | Col | Mengden | Promoted to active roster | | | Before |
| 5/6/2019 | Col | Pollock | Demoted to reserve roster | | | Before |
| 5/6/2019 | Col | Rodon | Demoted to reserve roster | | | Before |
| 5/6/2019 | Col | Taillon | Demoted to reserve roster | | | Before |
| 5/6/2019 | Mia | Avilan | Demoted to reserve roster | | | Before |
| 5/6/2019 | Mia | Guzman,R | Promoted to active roster | | | Before |
| 5/6/2019 | Mia | Matz | Demoted to reserve roster | | | Before |
| 5/6/2019 | Mia | Norris,D | Demoted to reserve roster | | | Before |
| 5/6/2019 | Mia | Norris,D | Promoted to active roster | | | Before |
| 5/6/2019 | Mia | Ross,J | Promoted to active roster | | | Before |
| 5/6/2019 | Pit | Andujar | Promoted to active roster | | | Before |
| 5/8/2019 | Cin | Whitlock | Released | | | Before |
| 5/10/2019 | Ari | Santana,Cr | Signed | | | Before |
| 5/10/2019 | ChN | Hall,M | Demoted to reserve roster | | | Before |
| 5/10/2019 | ChN | Happ,J | Promoted to active roster | | | Before |
| 5/10/2019 | Cin | Hoyt | Promoted to active roster | | | Before |
| 5/10/2019 | Cin | Mills,A | Demoted to reserve roster | | | Before |
| 5/10/2019 | Cin | Whitlock | Signed | | | Before |
| 5/10/2019 | NYN | Bailey,H | Released | | | Before |
| 5/10/2019 | Pit | Cabrera,Me | Signed | | | Before |
| 5/10/2019 | Pit | Zimmermann,J | Released | | | Before |
| 5/13/2019 | Atl | Morrison | Promoted to active roster | | | Before |
| 5/13/2019 | Atl | Perez,Mi | Demoted to reserve roster | | | Before |
| 5/13/2019 | Atl | Schreiber | Promoted to active roster | | | Before |
| 5/13/2019 | ChN | Chirinos,Y | Demoted to reserve roster | | | Before |
| 5/13/2019 | ChN | Hall,M | Promoted to active roster | | | Before |
| 5/13/2019 | ChN | Reed,M | Released | | | Before |
| 5/13/2019 | Cin | Riddle | Signed | | | Before |
| 5/13/2019 | Mia | Avilan | Released | | | Before |
| 5/13/2019 | Pit | Bautista,G | Released | | | Before |
| 5/13/2019 | Pit | Cedeno | Promoted to active roster | | | Before |
| 5/13/2019 | Pit | Estevez,O | Demoted to reserve roster | | | Before |
| 5/13/2019 | Pit | Kelley,S | Demoted to reserve roster | | | Before |
| 5/13/2019 | Pit | Pence | Signed | | | Before |
| 5/17/2019 | Ari | Cumberland | Released | | | Before |
| 5/17/2019 | Ari | Walsh | Signed | | | Before |
| 5/17/2019 | ChN | Andriese | Released | | | Before |
| 5/17/2019 | ChN | Chirinos,Y | Promoted to active roster | | | Before |
| 5/17/2019 | ChN | Dawson | Released | | | Before |
| 5/17/2019 | ChN | Hall,M | Demoted to reserve roster | | | Before |
| 5/17/2019 | ChN | Harper,R | Signed | | | Before |
| 5/17/2019 | ChN | Harper,R | Promoted to active roster | | | Before |
| 5/17/2019 | ChN | Minor | Demoted to reserve roster | | | Before |
| 5/17/2019 | ChN | Ramirez,Har | Signed | | | Before |
| 5/17/2019 | Cin | Bautista,G | Signed | | | Before |
| 5/17/2019 | Cin | Duda | Released | | | Before |
| 5/17/2019 | Cin | Ramos,H | Signed | | | Before |
| 5/17/2019 | Mia | Swihart | Released | | | Before |
| 5/17/2019 | Mia | Walden | Signed | | | Before |
| 5/17/2019 | Phi | Lyles | Demoted to reserve roster | | | Before |
| 5/17/2019 | Phi | Sabathia | Promoted to active roster | | | Before |
| 5/17/2019 | Pit | Woodford | Signed | | | Before |
| 5/17/2019 | Pit | Zimmermann,B | Signed | | | Before |
| 5/20/2019 | Ari | Arraez | Demoted to reserve roster | | | Before |
| 5/20/2019 | Ari | Meadows | Promoted to active roster | | | Before |
| 5/20/2019 | Ari | O'Hearn | Released | | | Before |
| 5/20/2019 | Ari | Senzel | Promoted to active roster | | | Before |
| 5/20/2019 | Ari | Supak | Demoted to reserve roster | | | Before |
| 5/20/2019 | Ari | Walsh | Promoted to active roster | | | Before |
| 5/20/2019 | Atl | Garcia,An | Demoted to reserve roster | | | Before |
| 5/20/2019 | Atl | Sano | Promoted to active roster | | | Before |
| 5/20/2019 | ChN | Hendriks | Demoted to reserve roster | | | Before |
| 5/20/2019 | ChN | Minor | Promoted to active roster | | | Before |
| 5/20/2019 | Cin | Boswell | Released | | | Before |
| 5/20/2019 | Cin | Ervin | Released | | | Before |
| 5/20/2019 | Cin | Grullon | Signed | | | Before |
| 5/20/2019 | Cin | Grullon | Promoted to active roster | | | Before |
| 5/20/2019 | Cin | O'Hearn | Signed | | | Before |
| 5/20/2019 | Cin | O'Hearn | Promoted to active roster | | | Before |
| 5/20/2019 | Cin | Osuna,J | Demoted to reserve roster | | | Before |
| 5/20/2019 | Cin | Pina | Demoted to reserve roster | | | Before |
| 5/20/2019 | Cin | Riddle | Demoted to reserve roster | | | Before |
| 5/20/2019 | Cin | Riddle | Promoted to active roster | | | Before |
| 5/20/2019 | Col | Biddle | Promoted to active roster | | | Before |
| 5/20/2019 | Col | Duggar | Demoted to reserve roster | | | Before |
| 5/20/2019 | Col | Estrada,T | Signed | | | Before |
| 5/20/2019 | Col | Ferguson,C | Promoted to active roster | | | Before |
| 5/20/2019 | Col | Frazier,C | Promoted to active roster | | | Before |
| 5/20/2019 | Col | Herget | Demoted to reserve roster | | | Before |
| 5/20/2019 | Col | Mengden | Demoted to reserve roster | | | Before |
| 5/20/2019 | Col | Perez,Hec | Released | | | Before |
| 5/20/2019 | Mia | Adon | Signed | | | Before |
| 5/20/2019 | Mil | Cease | Promoted to active roster | | | Before |
| 5/20/2019 | Mil | Conforto | Demoted to reserve roster | | | Before |
| 5/20/2019 | Mil | Hicks,A | Promoted to active roster | | | Before |
| 5/20/2019 | Mil | Robertson,Dav | Demoted to reserve roster | | | Before |
| 5/20/2019 | Mil | Shoemaker | Demoted to reserve roster | | | Before |
| 5/20/2019 | Mil | Stewart,D | Promoted to active roster | | | Before |
| 5/20/2019 | NYN | Robles,H | Signed | | | Before |
| 5/20/2019 | Phi | Barlow | Signed | | | Before |
| 5/20/2019 | Phi | Seabold | Released | | | Before |
| 5/20/2019 | Phi | Workman | Signed | | | Before |
| 5/20/2019 | Pit | Andujar | Demoted to reserve roster | | | Before |
| 5/20/2019 | Pit | Woodford | Promoted to active roster | | | Before |
| 5/23/2019 | Mia | Bauer | Acquired via trade | NYA | | After |
| 5/23/2019 | Mia | Hedges,A | Acquired via trade | NYA | | After |
| 5/23/2019 | Mia | Realmuto | Traded away | NYA | | After |
| 5/23/2019 | Mia | Rogers,Ja | Traded away | NYA | | After |
| 5/23/2019 | Mia | Ruiz,K | Acquired via trade | NYA | | After |
| 5/23/2019 | Mia | Verlander | Traded away | NYA | | After |
| 5/24/2019 | Ari | Avila,P | Released | | | Before |
| 5/24/2019 | Ari | Santana,Cr | Released | | | Before |
| 5/24/2019 | Atl | Garcia,An | Promoted to active roster | | | Before |
| 5/24/2019 | Atl | Nimmo | Demoted to reserve roster | | | Before |
| 5/24/2019 | ChN | Chirinos,Y | Demoted to reserve roster | | | Before |
| 5/24/2019 | ChN | Hendriks | Promoted to active roster | | | Before |
| 5/24/2019 | Cin | Ramos,H | Released | | | Before |
| 5/24/2019 | NYN | Holland,D | Released | | | Before |
| 5/24/2019 | NYN | Sandoval,Pab | Signed | | | Before |
| 5/24/2019 | Phi | Altherr | Released | | | Before |
| 5/24/2019 | Phi | Phegley | Signed | | | Before |
| 5/24/2019 | Pit | Kelley,S | Promoted to active roster | | | Before |
| 5/24/2019 | Pit | LeBlanc,W | Promoted to active roster | | | Before |
| 5/24/2019 | Pit | Murphy,P | Signed | | | Before |
| 5/24/2019 | Pit | Oliva | Released | | | Before |
| 5/24/2019 | Pit | Reks | Signed | | | Before |
| 5/24/2019 | Pit | Toffey | Released | | | Before |
| 5/24/2019 | Pit | Woodford | Released | | | Before |
| 5/27/2019 | ChN | Calhoun,W | Demoted to reserve roster | | | Before |
| 5/27/2019 | ChN | Campbell | Signed | | | Before |
| 5/27/2019 | ChN | Campbell | Promoted to active roster | | | Before |
| 5/27/2019 | ChN | Chirinos,Y | Promoted to active roster | | | Before |
| 5/27/2019 | ChN | Cronenworth | Promoted to active roster | | | Before |
| 5/27/2019 | ChN | Davis,K | Demoted to reserve roster | | | Before |
| 5/27/2019 | ChN | Espinal,S | Promoted to active roster | | | Before |
| 5/27/2019 | ChN | Hartman | Released | | | Before |
| 5/27/2019 | ChN | McNeil | Demoted to reserve roster | | | Before |
| 5/27/2019 | ChN | Minor | Demoted to reserve roster | | | Before |
| 5/27/2019 | ChN | Ramirez,Har | Promoted to active roster | | | Before |
| 5/27/2019 | ChN | Simmons,A | Demoted to reserve roster | | | Before |
| 5/27/2019 | Cin | German | Promoted to active roster | | | Before |
| 5/27/2019 | Cin | Hill,D | Signed | | | Before |
| 5/27/2019 | Cin | Loup | Released | | | Before |
| 5/27/2019 | Cin | McHugh | Demoted to reserve roster | | | Before |
| 5/27/2019 | Mia | Cozart,Z | Promoted to active roster | | | Before |
| 5/27/2019 | Mia | Drake | Demoted to reserve roster | | | Before |
| 5/27/2019 | Mia | Familia | Promoted to active roster | | | Before |
| 5/27/2019 | Mia | Guzman,R | Demoted to reserve roster | | | Before |
| 5/27/2019 | Mia | Matz | Promoted to active roster | | | Before |
| 5/27/2019 | Mia | Ross,J | Demoted to reserve roster | | | Before |
| 5/27/2019 | Mia | Rosscup | Demoted to reserve roster | | | Before |
| 5/27/2019 | Mia | Rosscup | Promoted to active roster | | | Before |
| 5/27/2019 | Mia | Seager,K | Promoted to active roster | | | Before |
| 5/27/2019 | Phi | Heaney | Promoted to active roster | | | Before |
| 5/27/2019 | Phi | Parra,G | Promoted to active roster | | | Before |
| 5/27/2019 | Phi | Peralta,D | Demoted to reserve roster | | | Before |
| 5/27/2019 | Phi | Sabathia | Demoted to reserve roster | | | Before |
| 5/29/2019 | SF | Duffy,M | Demoted to reserve roster | | | Before |
| 5/29/2019 | SF | Font | Promoted to active roster | | | Before |
| 5/29/2019 | SF | Kluber | Demoted to reserve roster | | | Before |
| 5/29/2019 | SF | Kopech | Promoted to active roster | | | Before |
| 5/29/2019 | SF | Webb,T | Promoted to active roster | | | Before |
| 5/31/2019 | Ari | Barrera,T | Released | | | Before |
| 5/31/2019 | Ari | Fried | Promoted to active roster | | | Before |
| 5/31/2019 | Ari | Hayes | Demoted to reserve roster | | | Before |
| 5/31/2019 | Ari | Loaisiga | Demoted to reserve roster | | | Before |
| 5/31/2019 | Ari | Supak | Promoted to active roster | | | Before |
| 5/31/2019 | Ari | Toro-Hernandez | Promoted to active roster | | | Before |
| 5/31/2019 | Atl | Gearrin | Promoted to active roster | | | Before |
| 5/31/2019 | Atl | Gott | Demoted to reserve roster | | | Before |
| 5/31/2019 | Atl | Mayza | Demoted to reserve roster | | | Before |
| 5/31/2019 | Atl | Shepherd | Promoted to active roster | | | Before |
| 5/31/2019 | Atl | Stock | Promoted to active roster | | | Before |
| 5/31/2019 | Atl | Whitley,F | Demoted to reserve roster | | | Before |
| 5/31/2019 | ChN | Chirinos,Y | Demoted to reserve roster | | | Before |
| 5/31/2019 | ChN | Cooper | Signed | | | Before |
| 5/31/2019 | ChN | Cooper | Promoted to active roster | | | Before |
| 5/31/2019 | ChN | Espinal,S | Released | | | Before |
| 5/31/2019 | ChN | Minor | Promoted to active roster | | | Before |
| 5/31/2019 | Cin | Almora | Promoted to active roster | | | Before |
| 5/31/2019 | Cin | Hill,D | Released | | | Before |
| 5/31/2019 | Cin | O'Hearn | Demoted to reserve roster | | | Before |
| 5/31/2019 | Cin | Ramos,H | Signed | | | Before |
| 5/31/2019 | Pit | Cabrera,Me | Released | | | Before |
| 5/31/2019 | Pit | Hechavarria | Signed | | | Before |
| 5/31/2019 | Pit | Pence | Promoted to active roster | | | Before |
| 5/31/2019 | Pit | Smeltzer | Signed | | | Before |
| 5/31/2019 | StL | Herrera,O | Released | | | Before |
| 6/2/2019 | Phi | Grichuk | Traded away | Det | | After |
| 6/3/2019 | ChN | Barnes,A | Demoted to reserve roster | | | Before |
| 6/3/2019 | ChN | Martini | Promoted to active roster | | | Before |
| 6/3/2019 | ChN | Ramirez,Har | Demoted to reserve roster | | | Before |
| 6/3/2019 | ChN | Ramirez,Har | Promoted to active roster | | | Before |
| 6/3/2019 | Cin | Gonzalez,G | Demoted to reserve roster | | | Before |
| 6/3/2019 | Cin | Grullon | Demoted to reserve roster | | | Before |
| 6/3/2019 | Cin | Mills,A | Promoted to active roster | | | Before |
| 6/3/2019 | Cin | Pina | Promoted to active roster | | | Before |
| 6/3/2019 | Col | Blackmon | Demoted to reserve roster | | | Before |
| 6/3/2019 | Col | Duggar | Promoted to active roster | | | Before |
| 6/3/2019 | Mia | Adon | Released | | | Before |
| 6/3/2019 | Mia | Cozart,Z | Demoted to reserve roster | | | Before |
| 6/3/2019 | Mia | Guzman,R | Promoted to active roster | | | Before |
| 6/3/2019 | NYN | Smith,Do | Promoted to active roster | | | Before |
| 6/3/2019 | NYN | Span | Demoted to reserve roster | | | Before |
| 6/3/2019 | Pit | Hechavarria | Released | | | Before |
| 6/3/2019 | Pit | Molina | Demoted to reserve roster | | | Before |
| 6/3/2019 | Pit | Pineda | Demoted to reserve roster | | | Before |
| 6/3/2019 | Pit | Rodney | Signed | | | Before |
| 6/3/2019 | Pit | Rodney | Promoted to active roster | | | Before |
| 6/3/2019 | Pit | Smeltzer | Promoted to active roster | | | Before |
| 6/3/2019 | StL | Gomber | Demoted to reserve roster | | | Before |
| 6/3/2019 | StL | McKenna | Promoted to active roster | | | Before |
| 6/3/2019 | StL | Skaggs | Promoted to active roster | | | Before |
| 6/5/2019 | Phi | Cervelli | Demoted to reserve roster | | | Before |
| 6/5/2019 | Phi | Gregerson | Promoted to active roster | | | Before |
| 6/5/2019 | Phi | Iannetta | Promoted to active roster | | | Before |
| 6/5/2019 | Phi | Neshek | Demoted to reserve roster | | | Before |
| 6/7/2019 | ChN | Chirinos,Y | Promoted to active roster | | | Before |
| 6/7/2019 | ChN | Kruczynski | Released | | | Before |
| 6/7/2019 | ChN | Minor | Demoted to reserve roster | | | Before |
| 6/7/2019 | Cin | Bautista,G | Promoted to active roster | | | Before |
| 6/7/2019 | Cin | Law,D | Demoted to reserve roster | | | Before |
| 6/7/2019 | Mia | Holloway | Released | | | Before |
| 6/7/2019 | Mia | Jackson,Al | Signed | | | Before |
| 6/7/2019 | Phi | Peralta,D | Promoted to active roster | | | Before |
| 6/7/2019 | Pit | Altherr | Signed | | | Before |
| 6/7/2019 | Pit | Altherr | Promoted to active roster | | | Before |
| 6/7/2019 | Pit | Civale | Signed | | | Before |
| 6/7/2019 | Pit | Reks | Released | | | Before |
| 6/7/2019 | Pit | Smeltzer | Demoted to reserve roster | | | Before |
| 6/7/2019 | Pit | Sosa | Released | | | Before |
| 6/7/2019 | Was | Carrasco | Demoted to reserve roster | | | Before |
| 6/7/2019 | Was | Waguespack | Promoted to active roster | | | Before |
| 6/9/2019 | Phi | Castillo,L | Traded away | Bos | | After |
| 6/9/2019 | Phi | Peralta,D | Traded away | Bos | | After |
| 6/9/2019 | Phi | Springer | Acquired via trade | Bos | | After |
| 6/9/2019 | Phi | Tejeda | Acquired via trade | Bos | | After |
| 6/9/2019 | Pit | Harvey,M | Demoted to reserve roster | | | Before |
| 6/9/2019 | Pit | Smeltzer | Promoted to active roster | | | Before |
| 6/9/2019 | SD | Correa | Demoted to reserve roster | | | Before |
| 6/10/2019 | ChN | Chirinos,Y | Demoted to reserve roster | | | Before |
| 6/10/2019 | ChN | Cronenworth | Demoted to reserve roster | | | Before |
| 6/10/2019 | ChN | Davis,K | Promoted to active roster | | | Before |
| 6/10/2019 | ChN | Dickerson,A | Demoted to reserve roster | | | Before |
| 6/10/2019 | ChN | Hendriks | Demoted to reserve roster | | | Before |
| 6/10/2019 | ChN | Keuchel | Promoted to active roster | | | Before |
| 6/10/2019 | ChN | McNeil | Promoted to active roster | | | Before |
| 6/10/2019 | ChN | Minor | Promoted to active roster | | | Before |
| 6/10/2019 | ChN | Pirela | Promoted to active roster | | | Before |
| 6/10/2019 | ChN | Ramirez,Har | Demoted to reserve roster | | | Before |
| 6/10/2019 | Cin | Aquino | Signed | | | Before |
| 6/10/2019 | Col | Viloria | Signed | | | Before |
| 6/10/2019 | Mia | Alford | Demoted to reserve roster | | | Before |
| 6/10/2019 | Mia | Gregorius | Promoted to active roster | | | Before |
| 6/10/2019 | Phi | Sabathia | Promoted to active roster | | | Before |
| 6/10/2019 | Pit | Gallo | Demoted to reserve roster | | | Before |
| 6/10/2019 | Pit | Moreland | Demoted to reserve roster | | | Before |
| 6/10/2019 | Pit | Murphy,P | Promoted to active roster | | | Before |
| 6/10/2019 | SD | Stassi,M | Demoted to reserve roster | | | Before |
| 6/10/2019 | StL | Woodford | Signed | | | Before |
| 6/12/2019 | SF | Posey | Demoted to reserve roster | | | Before |
| 6/13/2019 | Col | Frazier,C | Traded away | Was | | After |
| 6/13/2019 | Col | Giolito | Traded away | Was | | After |
| 6/13/2019 | Col | Grandal | Acquired via trade | Was | | After |
| 6/13/2019 | Col | Hendricks | Acquired via trade | Was | | After |
| 6/13/2019 | Col | Melancon | Acquired via trade | Was | | After |
| 6/13/2019 | Col | Merrifield | Acquired via trade | Was | | After |
| 6/13/2019 | Col | Trammell | Traded away | Was | | After |
| 6/13/2019 | Phi | Eaton | Acquired via trade | Was | | After |
| 6/13/2019 | Phi | Irvin | Traded away | Was | | After |
| 6/13/2019 | Phi | Jansen,K | Acquired via trade | Was | | After |
| 6/13/2019 | Phi | Kepler | Traded away | Was | | After |
| 6/13/2019 | Phi | McCullers | Traded away | Was | | After |
| 6/13/2019 | Phi | Rogers,Ta | Acquired via trade | Was | | After |
| 6/13/2019 | Phi | Tejeda | Traded away | Was | | After |
| 6/13/2019 | Phi | Turner,Ju | Acquired via trade | Was | | After |
| 6/13/2019 | Pit | Andujar | Traded away | Was | | After |
| 6/13/2019 | Pit | Carpenter,M | Acquired via trade | Was | | After |
| 6/13/2019 | Pit | Carrasco | Acquired via trade | Was | | After |
| 6/13/2019 | Pit | Civale | Traded away | Was | | After |
| 6/13/2019 | Pit | Gardner | Acquired via trade | Was | | After |
| 6/13/2019 | Pit | Howard,B | Traded away | Was | | After |
| 6/13/2019 | Pit | Wood,A | Acquired via trade | Was | | After |
| 6/13/2019 | Was | Andujar | Acquired via trade | Pit | | After |
| 6/13/2019 | Was | Barreto | Acquired via trade | Hou | | After |
| 6/13/2019 | Was | Carpenter,M | Traded away | Pit | | After |
| 6/13/2019 | Was | Carrasco | Traded away | Pit | | After |
| 6/13/2019 | Was | Civale | Acquired via trade | Pit | | After |
| 6/13/2019 | Was | Eaton | Traded away | Phi | | After |
| 6/13/2019 | Was | Frazier,C | Acquired via trade | Col | | After |
| 6/13/2019 | Was | Gardner | Traded away | Pit | | After |
| 6/13/2019 | Was | Giolito | Acquired via trade | Col | | After |
| 6/13/2019 | Was | Grandal | Traded away | Col | | After |
| 6/13/2019 | Was | Hendricks | Traded away | Col | | After |
| 6/13/2019 | Was | Howard,B | Acquired via trade | Pit | | After |
| 6/13/2019 | Was | Irvin | Acquired via trade | Phi | | After |
| 6/13/2019 | Was | Jansen,K | Traded away | Phi | | After |
| 6/13/2019 | Was | Kepler | Acquired via trade | Phi | | After |
| 6/13/2019 | Was | Marte,S | Traded away | Hou | | After |
| 6/13/2019 | Was | McCullers | Acquired via trade | Phi | | After |
| 6/13/2019 | Was | Melancon | Traded away | Col | | After |
| 6/13/2019 | Was | Merrifield | Traded away | Col | | After |
| 6/13/2019 | Was | Neidert | Acquired via trade | Hou | | After |
| 6/13/2019 | Was | Rogers,Ta | Traded away | Phi | | After |
| 6/13/2019 | Was | Tejeda | Acquired via trade | Phi | | After |
| 6/13/2019 | Was | Trammell | Acquired via trade | Col | | After |
| 6/13/2019 | Was | Turner,Ju | Traded away | Phi | | After |
| 6/13/2019 | Was | Wood,A | Traded away | Pit | | After |
| 6/14/2019 | ChN | Gonzalez,Ch | Demoted to reserve roster | | | Before |
| 6/14/2019 | ChN | Hall,M | Released | | | Before |
| 6/14/2019 | ChN | Hendriks | Promoted to active roster | | | Before |
| 6/14/2019 | Cin | Armstrong | Demoted to reserve roster | | | Before |
| 6/14/2019 | Cin | Gallen | Promoted to active roster | | | Before |
| 6/14/2019 | Cin | German | Demoted to reserve roster | | | Before |
| 6/14/2019 | Cin | Law,D | Promoted to active roster | | | Before |
| 6/14/2019 | Cin | Osuna,J | Promoted to active roster | | | Before |
| 6/14/2019 | Cin | Urias,R | Demoted to reserve roster | | | Before |
| 6/14/2019 | Col | Blackmon | Promoted to active roster | | | Before |
| 6/14/2019 | Col | Duplantier | Demoted to reserve roster | | | Before |
| 6/14/2019 | Col | Kintzler | Demoted to reserve roster | | | Before |
| 6/14/2019 | Col | Martin,Jas | Demoted to reserve roster | | | Before |
| 6/14/2019 | Col | Nottingham | Demoted to reserve roster | | | Before |
| 6/14/2019 | NYN | Conley | Released | | | Before |
| 6/14/2019 | Phi | Capps | Released | | | Before |
| 6/14/2019 | Phi | Givens | Demoted to reserve roster | | | Before |
| 6/14/2019 | Phi | Miller,Bra | Demoted to reserve roster | | | Before |
| 6/14/2019 | Pit | Altherr | Released | | | Before |
| 6/14/2019 | Pit | Reks | Signed | | | Before |
| 6/14/2019 | Was | Beaty | Released | | | Before |
| 6/14/2019 | Was | Blash | Released | | | Before |
| 6/14/2019 | Was | Kent | Released | | | Before |
| 6/14/2019 | Was | Waguespack | Released | | | Before |
| 6/14/2019 | Was | White,El | Signed | | | Before |
| 6/16/2019 | Cin | Armstrong | Traded away | Det | | After |
| 6/16/2019 | Cin | Romero,Jo | Acquired via trade | Det | | After |
| 6/16/2019 | Pit | Molina | Promoted to active roster | | | Before |
| 6/16/2019 | Pit | Murphy,P | Demoted to reserve roster | | | Before |
| 6/16/2019 | Pit | Gordon,D | Acquired via trade | Oak | | After |
| 6/16/2019 | Pit | Leyba | Traded away | Oak | | After |
| 6/16/2019 | Pit | Pazos | Acquired via trade | Oak | | After |
| 6/16/2019 | Pit | Pinder,Chad | Acquired via trade | Oak | | After |
| 6/16/2019 | Was | Thomas | Acquired via trade | Tam | | After |
| 6/16/2019 | Was | Villar | Traded away | Tam | | After |
| 6/17/2019 | Ari | McCarthy,J | Signed | | | Before |
| 6/17/2019 | ChN | Barnes,A | Promoted to active roster | | | Before |
| 6/17/2019 | ChN | Brennan | Demoted to reserve roster | | | Before |
| 6/17/2019 | ChN | Dean,A | Demoted to reserve roster | | | Before |
| 6/17/2019 | ChN | Dean,A | Promoted to active roster | | | Before |
| 6/17/2019 | ChN | Gibaut | Promoted to active roster | | | Before |
| 6/17/2019 | ChN | James,J | Promoted to active roster | | | Before |
| 6/17/2019 | ChN | Kittredge | Signed | | | Before |
| 6/17/2019 | ChN | McCurry | Demoted to reserve roster | | | Before |
| 6/17/2019 | ChN | Zagunis | Demoted to reserve roster | | | Before |
| 6/17/2019 | Cin | Ramos,H | Released | | | Before |
| 6/17/2019 | Col | Hendricks | Demoted to reserve roster | | | Before |
| 6/17/2019 | Col | Kuhl | Released | | | Before |
| 6/17/2019 | Col | Mengden | Promoted to active roster | | | Before |
| 6/17/2019 | Col | Viloria | Released | | | Before |
| 6/17/2019 | Pit | Gordon,D | Promoted to active roster | | | Before |
| 6/17/2019 | Pit | Harvey,M | Released | | | Before |
| 6/17/2019 | Pit | LeBlanc,W | Demoted to reserve roster | | | Before |
| 6/17/2019 | Pit | LeBlanc,W | Promoted to active roster | | | Before |
| 6/17/2019 | Pit | Oh | Demoted to reserve roster | | | Before |
| 6/17/2019 | Pit | Pineda | Promoted to active roster | | | Before |
| 6/17/2019 | Pit | Smeltzer | Demoted to reserve roster | | | Before |
| 6/17/2019 | Pit | Thornton | Demoted to reserve roster | | | Before |
| 6/17/2019 | Pit | Thornton | Promoted to active roster | | | Before |
| 6/17/2019 | Pit | Wainwright | Demoted to reserve roster | | | Before |
| 6/17/2019 | Was | Barraclough | Demoted to reserve roster | | | Before |
| 6/17/2019 | Was | Barraclough | Promoted to active roster | | | Before |
| 6/17/2019 | Was | Cave | Promoted to active roster | | | Before |
| 6/17/2019 | Was | Drury | Promoted to active roster | | | Before |
| 6/17/2019 | Was | Gonzalez,Ca | Promoted to active roster | | | Before |
| 6/17/2019 | Was | Howard,B | Promoted to active roster | | | Before |
| 6/17/2019 | Was | Jennings | Promoted to active roster | | | Before |
| 6/17/2019 | Was | Martin,Ch | Promoted to active roster | | | Before |
| 6/17/2019 | Was | Petit,Y | Promoted to active roster | | | Before |
| 6/17/2019 | Was | Tejeda | Demoted to reserve roster | | | Before |
| 6/17/2019 | Was | Thomas | Demoted to reserve roster | | | Before |
| 6/17/2019 | Was | Trammell | Promoted to active roster | | | Before |
| 6/17/2019 | Was | Wolters | Promoted to active roster | | | Before |
| 6/20/2019 | Was | Barreto | Traded away | KC | | After |
| 6/20/2019 | Was | Bichette | Acquired via trade | KC | | After |
| 6/20/2019 | Was | Hudson,Dak | Acquired via trade | KC | | After |
| 6/20/2019 | Was | Trammell | Traded away | KC | | After |
| 6/21/2019 | Ari | McCarthy,J | Released | | | Before |
| 6/21/2019 | Atl | Garcia,An | Demoted to reserve roster | | | Before |
| 6/21/2019 | Atl | Gott | Promoted to active roster | | | Before |
| 6/21/2019 | Atl | Mayza | Promoted to active roster | | | Before |
| 6/21/2019 | Atl | Miller,S | Demoted to reserve roster | | | Before |
| 6/21/2019 | Atl | Perez,Mi | Promoted to active roster | | | Before |
| 6/21/2019 | Atl | Stock | Demoted to reserve roster | | | Before |
| 6/21/2019 | ChN | Gonzalez,Ch | Promoted to active roster | | | Before |
| 6/21/2019 | ChN | Keuchel | Demoted to reserve roster | | | Before |
| 6/21/2019 | Pit | Gardner | Demoted to reserve roster | | | Before |
| 6/21/2019 | Pit | Moreland | Released | | | Before |
| 6/21/2019 | Pit | Murphy,P | Released | | | Before |
| 6/21/2019 | Pit | O'Day | Signed | | | Before |
| 6/21/2019 | Pit | Stanton | Promoted to active roster | | | Before |
| 6/21/2019 | Was | Bichette | Promoted to active roster | | | Before |
| 6/21/2019 | Was | Blandino | Promoted to active roster | | | Before |
| 6/21/2019 | Was | Howard,B | Demoted to reserve roster | | | Before |
| 6/23/2019 | StL | Petit,Y | Acquired via trade | Was | | After |
| 6/23/2019 | Was | Kiermaier | Traded away | NYA | | After |
| 6/23/2019 | Was | Pearce | Traded away | NYA | | After |
| 6/23/2019 | Was | Petit,Y | Traded away | StL | | After |
| 6/23/2019 | Was | Trivino | Traded away | NYA | | After |
| 6/24/2019 | Ari | McCarthy,J | Signed | | | Before |
| 6/24/2019 | Atl | Miller,S | Released | | | Before |
| 6/24/2019 | Atl | Villines | Signed | | | Before |
| 6/24/2019 | ChN | Calhoun,W | Promoted to active roster | | | Before |
| 6/24/2019 | ChN | Dean,A | Released | | | Before |
| 6/24/2019 | ChN | James,J | Demoted to reserve roster | | | Before |
| 6/24/2019 | ChN | Keuchel | Promoted to active roster | | | Before |
| 6/24/2019 | ChN | Kittredge | Promoted to active roster | | | Before |
| 6/24/2019 | ChN | Minor | Demoted to reserve roster | | | Before |
| 6/24/2019 | Cin | Diaz,Yu | Promoted to active roster | | | Before |
| 6/24/2019 | Cin | Gallen | Demoted to reserve roster | | | Before |
| 6/24/2019 | Cin | Gonzalez,Ma | Demoted to reserve roster | | | Before |
| 6/24/2019 | Cin | Romero,Jo | Demoted to reserve roster | | | Before |
| 6/24/2019 | Col | Duggar | Demoted to reserve roster | | | Before |
| 6/24/2019 | Col | Herget | Promoted to active roster | | | Before |
| 6/24/2019 | Col | Holloway | Signed | | | Before |
| 6/24/2019 | Col | Martin,Jas | Released | | | Before |
| 6/24/2019 | Col | Nottingham | Promoted to active roster | | | Before |
| 6/24/2019 | Col | Treinen | Demoted to reserve roster | | | Before |
| 6/24/2019 | Phi | Garlick | Signed | | | Before |
| 6/24/2019 | Pit | Cedeno | Demoted to reserve roster | | | Before |
| 6/24/2019 | Pit | Gardner | Promoted to active roster | | | Before |
| 6/24/2019 | Pit | Hill,R | Demoted to reserve roster | | | Before |
| 6/24/2019 | Pit | Pence | Demoted to reserve roster | | | Before |
| 6/24/2019 | Pit | Smeltzer | Promoted to active roster | | | Before |
| 6/24/2019 | StL | Adams,M | Promoted to active roster | | | Before |
| 6/24/2019 | StL | Bishop | Demoted to reserve roster | | | Before |
| 6/24/2019 | StL | Dalbec | Demoted to reserve roster | | | Before |
| 6/24/2019 | StL | Dalbec | Promoted to active roster | | | Before |
| 6/24/2019 | StL | Vincent | Demoted to reserve roster | | | Before |
| 6/24/2019 | Was | Barraclough | Promoted to active roster | | | Before |
| 6/24/2019 | Was | Drury | Released | | | Before |
| 6/24/2019 | Was | Howard,B | Promoted to active roster | | | Before |
| 6/24/2019 | Was | Matijevic | Signed | | | Before |
| 6/24/2019 | Was | Tejeda | Promoted to active roster | | | Before |
| 6/24/2019 | Was | Thomas | Promoted to active roster | | | Before |
| 6/24/2019 | Was | White,El | Promoted to active roster | | | Before |
| 6/26/2019 | Pit | Means | Demoted to reserve roster | | | Before |
| 6/26/2019 | Pit | Wainwright | Promoted to active roster | | | Before |
| 6/27/2019 | Mia | Gordon,D | Acquired via trade | Pit | | After |
| 6/27/2019 | Mia | Moncada | Traded away | Pit | | After |
| 6/27/2019 | Mia | Schwarber | Traded away | Pit | | After |
| 6/27/2019 | Mia | Stanton | Acquired via trade | Pit | | After |
| 6/27/2019 | Pit | Fiers | Acquired via trade | StL | | After |
| 6/27/2019 | Pit | Gordon,D | Traded away | Mia | | After |
| 6/27/2019 | Pit | Moncada | Acquired via trade | Mia | | After |
| 6/27/2019 | Pit | Munoz,Y | Traded away | StL | | After |
| 6/27/2019 | Pit | Schwarber | Acquired via trade | Mia | | After |
| 6/27/2019 | Pit | Stanton | Traded away | Mia | | After |
| 6/27/2019 | StL | Fiers | Traded away | Pit | | After |
| 6/27/2019 | StL | Munoz,Y | Acquired via trade | Pit | | After |
| 6/27/2019 | StL | Soler | Traded away | Min | | After |
| 6/28/2019 | ChN | Gonzalez,Ch | Demoted to reserve roster | | | Before |
| 6/28/2019 | ChN | Minor | Promoted to active roster | | | Before |
| 6/28/2019 | Cin | Diaz,Yu | Demoted to reserve roster | | | Before |
| 6/28/2019 | Cin | McHugh | Promoted to active roster | | | Before |
| 6/28/2019 | Cin | VanMeter | Promoted to active roster | | | Before |
| 6/28/2019 | Col | Biddle | Released | | | Before |
| 6/28/2019 | Mia | Cozart,Z | Released | | | Before |
| 6/28/2019 | Mia | Jackson,Al | Released | | | Before |
| 6/28/2019 | Phi | Bailey,H | Signed | | | Before |
| 6/28/2019 | Phi | Krook | Released | | | Before |
| 6/28/2019 | Pit | Gallo | Promoted to active roster | | | Before |
| 6/28/2019 | Pit | Kinsler | Demoted to reserve roster | | | Before |
| 6/28/2019 | Pit | Lamb,Ja | Promoted to active roster | | | Before |
| 6/28/2019 | StL | Deetz | Released | | | Before |
| 6/28/2019 | StL | Fernandez,Jun | Signed | | | Before |
| 6/28/2019 | Was | Beaty | Signed | | | Before |
| 6/30/2019 | Col | Ahmed,N | Acquired via trade | Was | | After |
| 6/30/2019 | Col | Arcia,O | Traded away | Was | | After |
| 6/30/2019 | Col | Chafin | Acquired via trade | Was | | After |
| 6/30/2019 | Col | Chirinos,R | Acquired via trade | Was | | After |
| 6/30/2019 | Col | Nottingham | Traded away | Was | | After |
| 6/30/2019 | Was | Ahmed,N | Traded away | Col | | After |
| 6/30/2019 | Was | Arcia,O | Acquired via trade | Col | | After |
| 6/30/2019 | Was | Bote | Acquired via trade | Bos | | After |
| 6/30/2019 | Was | Cabrera,A | Traded away | Bos | | After |
| 6/30/2019 | Was | Chafin | Traded away | Col | | After |
| 6/30/2019 | Was | Chirinos,R | Traded away | Col | | After |
| 6/30/2019 | Was | Nottingham | Acquired via trade | Col | | After |
| 7/1/2019 | Ari | Capel | Signed | | | Before |
| 7/1/2019 | Ari | Hentges | Released | | | Before |
| 7/1/2019 | ChN | Dean,A | Released | | | Before |
| 7/1/2019 | ChN | Dean,A | Signed | | | Before |
| 7/1/2019 | ChN | Gibaut | Demoted to reserve roster | | | Before |
| 7/1/2019 | ChN | Gonzalez,Ch | Promoted to active roster | | | Before |
| 7/1/2019 | ChN | Keuchel | Demoted to reserve roster | | | Before |
| 7/1/2019 | ChN | McCurry | Promoted to active roster | | | Before |
| 7/1/2019 | ChN | Pirela | Demoted to reserve roster | | | Before |
| 7/1/2019 | ChN | Simmons,A | Promoted to active roster | | | Before |
| 7/1/2019 | ChN | Zagunis | Demoted to reserve roster | | | Before |
| 7/1/2019 | ChN | Zagunis | Promoted to active roster | | | Before |
| 7/1/2019 | Cin | Gallen | Promoted to active roster | | | Before |
| 7/1/2019 | Cin | Peacock | Demoted to reserve roster | | | Before |
| 7/1/2019 | Col | Chirinos,R | Demoted to reserve roster | | | Before |
| 7/1/2019 | Mia | Gausman | Demoted to reserve roster | | | Before |
| 7/1/2019 | Mia | Ross,J | Promoted to active roster | | | Before |
| 7/1/2019 | Mia | Stanton | Demoted to reserve roster | | | Before |
| 7/1/2019 | Mia | Wade,L | Signed | | | Before |
| 7/1/2019 | Mia | Wade,L | Promoted to active roster | | | Before |
| 7/1/2019 | NYN | Fisher | Promoted to active roster | | | Before |
| 7/1/2019 | NYN | Ramirez,Han | Demoted to reserve roster | | | Before |
| 7/1/2019 | Phi | Ozuna | Demoted to reserve roster | | | Before |
| 7/1/2019 | Phi | Springer | Promoted to active roster | | | Before |
| 7/1/2019 | Pit | Freese | Demoted to reserve roster | | | Before |
| 7/1/2019 | Pit | Kinsler | Promoted to active roster | | | Before |
| 7/1/2019 | Pit | Sneed | Signed | | | Before |
| 7/1/2019 | StL | Arauz,J | Promoted to active roster | | | Before |
| 7/1/2019 | StL | Barnhart | Demoted to reserve roster | | | Before |
| 7/1/2019 | StL | Dalbec | Promoted to active roster | | | Before |
| 7/1/2019 | StL | Dominguez,S | Demoted to reserve roster | | | Before |
| 7/1/2019 | StL | Fernandez,Jun | Promoted to active roster | | | Before |
| 7/1/2019 | StL | Martin,Cor | Demoted to reserve roster | | | Before |
| 7/1/2019 | StL | Muller | Promoted to active roster | | | Before |
| 7/1/2019 | StL | Skaggs | Demoted to reserve roster | | | Before |
| 7/1/2019 | StL | Tanielu | Promoted to active roster | | | Before |
| 7/1/2019 | StL | Woodford | Promoted to active roster | | | Before |
| 7/1/2019 | Was | Barraclough | Released | | | Before |
| 7/1/2019 | Was | Brigham | Signed | | | Before |
| 7/1/2019 | Was | Perdomo,L | Signed | | | Before |
| 7/3/2019 | Pit | Briceno | Demoted to reserve roster | | | Before |
| 7/5/2019 | Ari | Capel | Released | | | Before |
| 7/5/2019 | ChN | Gonzalez,Ch | Demoted to reserve roster | | | Before |
| 7/5/2019 | ChN | Hendriks | Demoted to reserve roster | | | Before |
| 7/5/2019 | ChN | Keuchel | Promoted to active roster | | | Before |
| 7/5/2019 | ChN | Minor | Demoted to reserve roster | | | Before |
| 7/5/2019 | ChN | Pirela | Promoted to active roster | | | Before |
| 7/5/2019 | ChN | Zagunis | Promoted to active roster | | | Before |
| 7/5/2019 | Cin | Ervin | Signed | | | Before |
| 7/5/2019 | Cin | Gallen | Demoted to reserve roster | | | Before |
| 7/5/2019 | Cin | German | Promoted to active roster | | | Before |
| 7/5/2019 | Cin | Gonzalez,Ma | Promoted to active roster | | | Before |
| 7/5/2019 | Cin | VanMeter | Demoted to reserve roster | | | Before |
| 7/5/2019 | Col | Chafin | Demoted to reserve roster | | | Before |
| 7/5/2019 | Col | Hendricks | Promoted to active roster | | | Before |
| 7/5/2019 | Col | Mengden | Demoted to reserve roster | | | Before |
| 7/5/2019 | Col | Treinen | Promoted to active roster | | | Before |
| 7/5/2019 | LAN | Castillo,D | Demoted to reserve roster | | | Before |
| 7/5/2019 | LAN | Lewis,K | Promoted to active roster | | | Before |
| 7/5/2019 | LAN | Piscotty | Demoted to reserve roster | | | Before |
| 7/5/2019 | LAN | Sobotka | Promoted to active roster | | | Before |
| 7/5/2019 | LAN | Thaiss | Demoted to reserve roster | | | Before |
| 7/5/2019 | LAN | Thaiss | Promoted to active roster | | | Before |
| 7/5/2019 | Mia | Duffey | Signed | | | Before |
| 7/5/2019 | StL | Robinson,S | Signed | | | Before |
| 7/5/2019 | Was | Brigham | Released | | | Before |
| 7/5/2019 | Was | Brigman | Released | | | Before |
| 7/5/2019 | Was | Urena,Jo | Signed | | | Before |
| 7/7/2019 | Cin | O'Hearn | Released | | | Before |
| 7/7/2019 | Cin | Riddle | Released | | | Before |
| 7/7/2019 | Cin | Adams,M | Acquired via trade | StL | | After |
| 7/7/2019 | Cin | Romero,Jo | Traded away | StL | | After |
| 7/7/2019 | Col | Andrus | Acquired via trade | StL | | After |
| 7/7/2019 | Mia | Erlin | Acquired via trade | Tex | | After |
| 7/7/2019 | Mia | Familia | Traded away | Pit | | After |
| 7/7/2019 | Mia | Lynn | Traded away | Pit | | After |
| 7/7/2019 | Mia | Oliva | Acquired via trade | Pit | | After |
| 7/7/2019 | Mia | Schwarber | Acquired via trade | Pit | | After |
| 7/7/2019 | Pit | Estevez,O | Traded away | Min | | After |
| 7/7/2019 | Pit | Familia | Acquired via trade | Mia | | After |
| 7/7/2019 | Pit | Lynn | Acquired via trade | Mia | | After |
| 7/7/2019 | Pit | McCutchen | Acquired via trade | Min | | After |
| 7/7/2019 | Pit | Oliva | Traded away | Mia | | After |
| 7/7/2019 | Pit | Schwarber | Traded away | Mia | | After |
| 7/7/2019 | Pit | Thornton | Traded away | Min | | After |
| 7/7/2019 | SF | Bush | Demoted to reserve roster | | | Before |
| 7/7/2019 | SF | Kopech | Demoted to reserve roster | | | Before |
| 7/7/2019 | SF | Lowrie | Demoted to reserve roster | | | Before |
| 7/7/2019 | StL | Adams,M | Traded away | Cin | | After |
| 7/7/2019 | StL | Andrus | Traded away | Col | | After |
| 7/7/2019 | StL | Romero,Jo | Acquired via trade | Cin | | After |
| 7/7/2019 | Was | Bote | Traded away | ChA | | After |
| 7/7/2019 | Was | Bradley,B | Acquired via trade | ChA | | After |
| 7/7/2019 | Was | Giolito | Traded away | Hou | | After |
| 7/7/2019 | Was | Hudson,Dak | Traded away | ChA | | After |
| 7/7/2019 | Was | Jennings | Traded away | LAA | | After |
| 7/7/2019 | Was | Kepler | Traded away | ChA | | After |
| 7/7/2019 | Was | McCullers | Traded away | Tex | | After |
| 7/7/2019 | Was | Sanchez,J | Acquired via trade | Tex | | After |
| 7/7/2019 | Was | Welker | Acquired via trade | ChA | | After |
| 7/7/2019 | Was | Wright,K | Acquired via trade | ChA | | After |
| 7/11/2019 | Atl | Castro,D | Demoted to reserve roster | | | Before |
| 7/11/2019 | Atl | Craig,W | Promoted to active roster | | | Before |
| 7/11/2019 | Atl | Jones,Jah | Promoted to active roster | | | Before |
| 7/11/2019 | Atl | Maybin | Demoted to reserve roster | | | Before |
| 7/11/2019 | Atl | Mercado | Promoted to active roster | | | Before |
| 7/11/2019 | Atl | Morrison | Demoted to reserve roster | | | Before |
| 7/11/2019 | ChN | Dean,A | Signed | | | Before |
| 7/11/2019 | ChN | Hendriks | Promoted to active roster | | | Before |
| 7/11/2019 | ChN | Pirela | Demoted to reserve roster | | | Before |
| 7/11/2019 | Cin | Almora | Demoted to reserve roster | | | Before |
| 7/11/2019 | Cin | Avilan | Signed | | | Before |
| 7/11/2019 | Cin | Avilan | Promoted to active roster | | | Before |
| 7/11/2019 | Cin | German | Promoted to active roster | | | Before |
| 7/11/2019 | Cin | Jankowski | Signed | | | Before |
| 7/11/2019 | Cin | Schebler | Demoted to reserve roster | | | Before |
| 7/11/2019 | Cin | Steele | Released | | | Before |
| 7/11/2019 | Cin | Urias,R | Promoted to active roster | | | Before |
| 7/11/2019 | Cin | VanMeter | Demoted to reserve roster | | | Before |
| 7/11/2019 | Cin | Zamora | Demoted to reserve roster | | | Before |
| 7/11/2019 | Mia | Guerra,D | Released | | | Before |
| 7/11/2019 | Mia | Guerra,D | Signed | | | Before |
| 7/11/2019 | Mia | Wade,L | Released | | | Before |
| 7/11/2019 | Phi | Gregerson | Demoted to reserve roster | | | Before |
| 7/11/2019 | Phi | Hamels | Demoted to reserve roster | | | Before |
| 7/11/2019 | Phi | Hunter | Promoted to active roster | | | Before |
| 7/11/2019 | Phi | Lyles | Promoted to active roster | | | Before |
| 7/11/2019 | Pit | Lynn | Promoted to active roster | | | Before |
| 7/11/2019 | Pit | Means | Promoted to active roster | | | Before |
| 7/11/2019 | Pit | Oh | Released | | | Before |
| 7/11/2019 | Pit | Oliva | Signed | | | Before |
| 7/11/2019 | Pit | Pazos | Released | | | Before |
| 7/11/2019 | SF | Cozens | Released | | | Before |
| 7/11/2019 | SF | McBride | Signed | | | Before |
| 7/11/2019 | StL | Mercer | Released | | | Before |
| 7/11/2019 | Was | Perdomo,L | Released | | | Before |
| 7/11/2019 | Was | Perdomo,L | Released | | | Before |
| 7/11/2019 | Was | Perdomo,L | Signed | | | Before |
| 7/14/2019 | Mia | Walker,T | Acquired via trade | StL | | After |
| 7/14/2019 | NYN | Nottingham | Acquired via trade | Was | | After |
| 7/14/2019 | NYN | Wright,K | Acquired via trade | Was | | After |
| 7/14/2019 | Phi | Happ,I | Traded away | Oak | | After |
| 7/14/2019 | Phi | McCann,J | Traded away | Was | | After |
| 7/14/2019 | Phi | Pivetta | Acquired via trade | Oak | | After |
| 7/14/2019 | Phi | Wolters | Acquired via trade | Was | | After |
| 7/14/2019 | StL | Walker,T | Traded away | Mia | | After |
| 7/14/2019 | Was | Andujar | Traded away | KC | | After |
| 7/14/2019 | Was | McCann,J | Traded away | Min | | After |
| 7/14/2019 | Was | McCann,J | Acquired via trade | Phi | | After |
| 7/14/2019 | Was | Medina | Acquired via trade | KC | | After |
| 7/14/2019 | Was | Nottingham | Traded away | NYN | | After |
| 7/14/2019 | Was | Wolters | Traded away | Phi | | After |
| 7/14/2019 | Was | Wright,K | Traded away | NYN | | After |
| 7/15/2019 | ChN | Burke | Promoted to active roster | | | Before |
| 7/15/2019 | ChN | Dean,A | Released | | | Before |
| 7/15/2019 | ChN | Gonzalez,Ch | Promoted to active roster | | | Before |
| 7/15/2019 | ChN | Happ,J | Demoted to reserve roster | | | Before |
| 7/15/2019 | ChN | Hendriks | Demoted to reserve roster | | | Before |
| 7/15/2019 | ChN | Kittredge | Demoted to reserve roster | | | Before |
| 7/15/2019 | ChN | Minor | Promoted to active roster | | | Before |
| 7/15/2019 | Cin | Ervin | Released | | | Before |
| 7/15/2019 | Col | Pollock | Promoted to active roster | | | Before |
| 7/15/2019 | Col | Rojas,M | Demoted to reserve roster | | | Before |
| 7/15/2019 | Col | Wong,Ko | Demoted to reserve roster | | | Before |
| 7/15/2019 | Mia | Duffey | Released | | | Before |
| 7/15/2019 | Mia | Jackson,Al | Signed | | | Before |
| 7/15/2019 | Mia | Jackson,Al | Demoted to reserve roster | | | Before |
| 7/15/2019 | Mia | Jackson,Al | Promoted to active roster | | | Before |
| 7/15/2019 | Mia | Longoria | Demoted to reserve roster | | | Before |
| 7/15/2019 | Mia | Oliva | Promoted to active roster | | | Before |
| 7/15/2019 | Mia | Wheeler | Demoted to reserve roster | | | Before |
| 7/15/2019 | Phi | Bailey,H | Released | | | Before |
| 7/15/2019 | Phi | Pazos | Signed | | | Before |
| 7/15/2019 | Phi | Phegley | Released | | | Before |
| 7/15/2019 | Pit | Freese | Promoted to active roster | | | Before |
| 7/15/2019 | Pit | Molina | Demoted to reserve roster | | | Before |
| 7/15/2019 | Pit | Sneed | Promoted to active roster | | | Before |
| 7/15/2019 | SF | Anderson,S | Promoted to active roster | | | Before |
| 7/15/2019 | SF | Duffy,D | Promoted to active roster | | | Before |
| 7/15/2019 | SF | Gyorko | Demoted to reserve roster | | | Before |
| 7/15/2019 | SF | Jones,JaC | Promoted to active roster | | | Before |
| 7/15/2019 | SF | Suarez,A | Promoted to active roster | | | Before |
| 7/15/2019 | StL | Skaggs | Released | | | Before |
| 7/15/2019 | Was | Arcia,O | Promoted to active roster | | | Before |
| 7/15/2019 | Was | Civale | Promoted to active roster | | | Before |
| 7/15/2019 | Was | Harvey,H | Signed | | | Before |
| 7/15/2019 | Was | Harvey,H | Promoted to active roster | | | Before |
| 7/15/2019 | Was | Medina | Promoted to active roster | | | Before |
| 7/15/2019 | Was | Miroglio | Promoted to active roster | | | Before |
| 7/15/2019 | Was | Rutherford | Promoted to active roster | | | Before |
| 7/18/2019 | ChN | Martin,Ch | Acquired via trade | Was | | After |
| 7/18/2019 | Cin | Winker | Acquired via trade | Mia | | After |
| 7/18/2019 | Mia | Winker | Traded away | Cin | | After |
| 7/18/2019 | Pit | Diaz,El | Acquired via trade | Hou | | After |
| 7/18/2019 | Was | Frazier,C | Traded away | Cle | | After |
| 7/18/2019 | Was | Haseley | Acquired via trade | Cle | | After |
| 7/18/2019 | Was | Martin,Ch | Traded away | ChN | | After |
| 7/18/2019 | Was | Thomas | Traded away | Cle | | After |
| 7/19/2019 | Ari | Alvarado | Demoted to reserve roster | | | Before |
| 7/19/2019 | Ari | Bielak | Promoted to active roster | | | Before |
| 7/19/2019 | Ari | Burnes | Demoted to reserve roster | | | Before |
| 7/19/2019 | Ari | Cabrera,G | Promoted to active roster | | | Before |
| 7/19/2019 | Ari | Fried | Demoted to reserve roster | | | Before |
| 7/19/2019 | Ari | McCarthy,J | Promoted to active roster | | | Before |
| 7/19/2019 | ChN | Burke | Demoted to reserve roster | | | Before |
| 7/19/2019 | ChN | Dunshee | Released | | | Before |
| 7/19/2019 | ChN | Gonzalez,Ch | Demoted to reserve roster | | | Before |
| 7/19/2019 | ChN | Happ,J | Promoted to active roster | | | Before |
| 7/19/2019 | ChN | Hendriks | Promoted to active roster | | | Before |
| 7/19/2019 | ChN | Keuchel | Demoted to reserve roster | | | Before |
| 7/19/2019 | ChN | McCurry | Demoted to reserve roster | | | Before |
| 7/19/2019 | ChN | Ryan,K | Signed | | | Before |
| 7/19/2019 | ChN | Ryan,K | Promoted to active roster | | | Before |
| 7/19/2019 | Cin | Ferguson,D | Demoted to reserve roster | | | Before |
| 7/19/2019 | Cin | German | Demoted to reserve roster | | | Before |
| 7/19/2019 | Cin | Lakins | Released | | | Before |
| 7/19/2019 | Cin | Mejia,Ad | Signed | | | Before |
| 7/19/2019 | Cin | Mejia,Ad | Promoted to active roster | | | Before |
| 7/19/2019 | Cin | Osuna,J | Demoted to reserve roster | | | Before |
| 7/19/2019 | Cin | Schebler | Promoted to active roster | | | Before |
| 7/19/2019 | NYN | Espinal,R | Demoted to reserve roster | | | Before |
| 7/19/2019 | NYN | Mondesi | Demoted to reserve roster | | | Before |
| 7/19/2019 | NYN | Naquin | Promoted to active roster | | | Before |
| 7/19/2019 | NYN | Ott | Demoted to reserve roster | | | Before |
| 7/19/2019 | NYN | Quantrill | Promoted to active roster | | | Before |
| 7/19/2019 | NYN | Reed,AJ | Demoted to reserve roster | | | Before |
| 7/19/2019 | NYN | Staumont | Promoted to active roster | | | Before |
| 7/19/2019 | Pit | LeBlanc,W | Demoted to reserve roster | | | Before |
| 7/19/2019 | Was | Beaty | Promoted to active roster | | | Before |
| 7/19/2019 | Was | Fernandez,V | Signed | | | Before |
| 7/19/2019 | Was | Irvin | Promoted to active roster | | | Before |
| 7/19/2019 | Was | Melendez | Promoted to active roster | | | Before |
| 7/21/2019 | Atl | Cron,K | Acquired via trade | Det | | After |
| 7/21/2019 | Atl | Jeffress | Traded away | Det | | After |
| 7/21/2019 | Atl | Kay | Acquired via trade | Det | | After |
| 7/21/2019 | Atl | Sano | Traded away | Det | | After |
| 7/21/2019 | Mia | Davis,A | Acquired via trade | KC | | After |
| 7/21/2019 | Mia | Holder,J | Acquired via trade | Was | | After |
| 7/21/2019 | Mia | Kingery | Acquired via trade | KC | | After |
| 7/21/2019 | Mia | Oliva | Traded away | KC | | After |
| 7/21/2019 | Phi | Beaty | Acquired via trade | Was | | After |
| 7/21/2019 | Phi | Haseley | Acquired via trade | Was | | After |
| 7/21/2019 | SF | Arcia,O | Acquired via trade | Was | | After |
| 7/21/2019 | SF | Edman | Traded away | Was | | After |
| 7/21/2019 | SF | Harrison,M | Traded away | Was | | After |
| 7/21/2019 | SF | Kieboom,C | Traded away | Was | | After |
| 7/21/2019 | SF | Reynolds,B | Acquired via trade | Was | | After |
| 7/21/2019 | Was | Arcia,O | Traded away | SF | | After |
| 7/21/2019 | Was | Beaty | Traded away | Phi | | After |
| 7/21/2019 | Was | Edman | Acquired via trade | SF | | After |
| 7/21/2019 | Was | Harrison,M | Acquired via trade | SF | | After |
| 7/21/2019 | Was | Haseley | Traded away | Phi | | After |
| 7/21/2019 | Was | Holder,J | Traded away | Mia | | After |
| 7/21/2019 | Was | Kieboom,C | Acquired via trade | SF | | After |
| 7/21/2019 | Was | Reynolds,B | Traded away | SF | | After |
| 7/21/2019 | Was | Rogers,Ja | Acquired via trade | NYA | | After |
| 7/22/2019 | Atl | Castro,D | Released | | | Before |
| 7/22/2019 | Atl | Craig,W | Demoted to reserve roster | | | Before |
| 7/22/2019 | Atl | Cron,K | Promoted to active roster | | | Before |
| 7/22/2019 | Atl | Kay | Promoted to active roster | | | Before |
| 7/22/2019 | Atl | Morrison | Promoted to active roster | | | Before |
| 7/22/2019 | Atl | Pruitt | Demoted to reserve roster | | | Before |
| 7/22/2019 | Atl | Stock | Promoted to active roster | | | Before |
| 7/22/2019 | Atl | Villines | Promoted to active roster | | | Before |
| 7/22/2019 | Atl | Weiman | Demoted to reserve roster | | | Before |
| 7/22/2019 | ChN | Contreras | Demoted to reserve roster | | | Before |
| 7/22/2019 | ChN | Gonzalez,Ch | Promoted to active roster | | | Before |
| 7/22/2019 | ChN | Hendriks | Demoted to reserve roster | | | Before |
| 7/22/2019 | ChN | Keuchel | Promoted to active roster | | | Before |
| 7/22/2019 | ChN | Minor | Demoted to reserve roster | | | Before |
| 7/22/2019 | ChN | Pirela | Promoted to active roster | | | Before |
| 7/22/2019 | Cin | Gonzalez,G | Promoted to active roster | | | Before |
| 7/22/2019 | Cin | Jankowski | Released | | | Before |
| 7/22/2019 | Cin | Mills,A | Demoted to reserve roster | | | Before |
| 7/22/2019 | Mia | Bettencourt | Released | | | Before |
| 7/22/2019 | Mil | Anderson,Ta | Demoted to reserve roster | | | Before |
| 7/22/2019 | Mil | Barnette | Promoted to active roster | | | Before |
| 7/22/2019 | Mil | Bassitt | Promoted to active roster | | | Before |
| 7/22/2019 | Mil | Brito | Demoted to reserve roster | | | Before |
| 7/22/2019 | Mil | Brito | Promoted to active roster | | | Before |
| 7/22/2019 | Mil | Chatham | Demoted to reserve roster | | | Before |
| 7/22/2019 | Mil | Conforto | Promoted to active roster | | | Before |
| 7/22/2019 | Mil | Delgado | Demoted to reserve roster | | | Before |
| 7/22/2019 | Mil | Holt | Promoted to active roster | | | Before |
| 7/22/2019 | Mil | Smith,Joe | Promoted to active roster | | | Before |
| 7/22/2019 | Mil | Stammen | Demoted to reserve roster | | | Before |
| 7/22/2019 | Mil | Stewart,D | Demoted to reserve roster | | | Before |
| 7/22/2019 | NYN | Ramirez,Han | Released | | | Before |
| 7/22/2019 | Phi | Givens | Promoted to active roster | | | Before |
| 7/22/2019 | Phi | Heaney | Demoted to reserve roster | | | Before |
| 7/22/2019 | Phi | Hunter | Demoted to reserve roster | | | Before |
| 7/22/2019 | Phi | Wieters | Demoted to reserve roster | | | Before |
| 7/22/2019 | Pit | Carpenter,M | Demoted to reserve roster | | | Before |
| 7/22/2019 | Pit | LeBlanc,W | Promoted to active roster | | | Before |
| 7/22/2019 | Pit | Means | Demoted to reserve roster | | | Before |
| 7/22/2019 | Pit | Pence | Promoted to active roster | | | Before |
| 7/22/2019 | SF | Bush | Released | | | Before |
| 7/22/2019 | SF | Cahill | Released | | | Before |
| 7/22/2019 | SF | Heredia | Released | | | Before |
| 7/22/2019 | SF | Yastrzemski | Signed | | | Before |
| 7/22/2019 | Was | Bolt | Signed | | | Before |
| 7/22/2019 | Was | Harvey,H | Released | | | Before |
| 7/22/2019 | Was | Nunez,D | Signed | | | Before |
| 7/25/2019 | Ari | Castellanos | Traded away | Cle | | After |
| 7/25/2019 | Ari | Dunn,J | Acquired via trade | Cle | | After |
| 7/25/2019 | Was | Chisholm | Acquired via trade | Cle | | After |
| 7/26/2019 | Ari | Wong,Ke | Released | | | Before |
| 7/26/2019 | ChN | Gonzalez,Ch | Demoted to reserve roster | | | Before |
| 7/26/2019 | ChN | Hendriks | Promoted to active roster | | | Before |
| 7/26/2019 | Pit | Means | Promoted to active roster | | | Before |
| 7/26/2019 | Pit | Sneed | Released | | | Before |
| 7/26/2019 | Pit | Tomas | Signed | | | Before |
| 7/26/2019 | SF | Green,Z | Signed | | | Before |
| 7/26/2019 | Was | Gonzalez,Ca | Released | | | Before |
| 7/26/2019 | Was | Nelson,N | Signed | | | Before |
| 7/28/2019 | Ari | Bradley,A | Traded away | Pit | | After |
| 7/28/2019 | Pit | Bradley,A | Acquired via trade | Ari | | After |
| 7/29/2019 | Ari | Arraez | Promoted to active roster | | | Before |
| 7/29/2019 | Ari | Fried | Promoted to active roster | | | Before |
| 7/29/2019 | Ari | Hayes | Promoted to active roster | | | Before |
| 7/29/2019 | Ari | McCarthy,J | Released | | | Before |
| 7/29/2019 | Ari | Robert | Promoted to active roster | | | Before |
| 7/29/2019 | Ari | Robertson,Dan | Demoted to reserve roster | | | Before |
| 7/29/2019 | Ari | Stashak | Signed | | | Before |
| 7/29/2019 | Atl | Marvel | Signed | | | Before |
| 7/29/2019 | Atl | Maybin | Promoted to active roster | | | Before |
| 7/29/2019 | Atl | Shepherd | Released | | | Before |
| 7/29/2019 | Atl | Swanson,D | Demoted to reserve roster | | | Before |
| 7/29/2019 | Atl | Triggs | Released | | | Before |
| 7/29/2019 | Atl | Whitley,F | Promoted to active roster | | | Before |
| 7/29/2019 | ChN | Gonzalez,Ch | Promoted to active roster | | | Before |
| 7/29/2019 | ChN | Happ,J | Demoted to reserve roster | | | Before |
| 7/29/2019 | Mia | Gausman | Promoted to active roster | | | Before |
| 7/29/2019 | Mia | Jackson,Al | Promoted to active roster | | | Before |
| 7/29/2019 | Mia | Matz | Demoted to reserve roster | | | Before |
| 7/29/2019 | Mia | Ross,J | Demoted to reserve roster | | | Before |
| 7/29/2019 | Mia | Wheeler | Promoted to active roster | | | Before |
| 7/29/2019 | Pit | Briceno | Released | | | Before |
| 7/29/2019 | SF | Green,Z | Released | | | Before |
| 7/29/2019 | StL | Barnhart | Promoted to active roster | | | Before |
| 7/29/2019 | StL | Markakis | Demoted to reserve roster | | | Before |
| 7/29/2019 | StL | Mayers | Promoted to active roster | | | Before |
| 7/29/2019 | StL | Robinson,S | Promoted to active roster | | | Before |
| 7/29/2019 | Was | Chisholm | Promoted to active roster | | | Before |
| 7/29/2019 | Was | Fernandez,V | Released | | | Before |
| 7/29/2019 | Was | Feyereisen | Signed | | | Before |
| 7/29/2019 | Was | Feyereisen | Promoted to active roster | | | Before |
| 7/29/2019 | Was | Kieboom,C | Promoted to active roster | | | Before |
| 7/29/2019 | Was | Lively | Released | | | Before |
| 7/29/2019 | Was | Miroglio | Released | | | Before |
| 7/29/2019 | Was | Nelson,N | Promoted to active roster | | | Before |
| 7/29/2019 | Was | Reyes,V | Signed | | | Before |
| 7/29/2019 | Was | Rojas,Jose | Signed | | | Before |
| 7/29/2019 | Was | Wick | Signed | | | Before |
| 7/29/2019 | Was | Wick | Promoted to active roster | | | Before |
| 7/30/2019 | Cin | Stripling | Demoted to reserve roster | | | Before |
| 7/30/2019 | Pit | Gallo | Demoted to reserve roster | | | Before |
| 7/30/2019 | Pit | Gardner | Demoted to reserve roster | | | Before |
| 7/30/2019 | Pit | Kelley,S | Demoted to reserve roster | | | Before |
| 7/30/2019 | Pit | Means | Demoted to reserve roster | | | Before |
| 7/30/2019 | Pit | Tomas | Promoted to active roster | | | Before |
| 8/1/2019 | Mia | Bradley,A | Acquired via trade | Pit | | After |
| 8/1/2019 | Pit | Anderson,Bri | Acquired via trade | Tex | | After |
| 8/1/2019 | Pit | Bird,G | Traded away | Tex | | After |
| 8/1/2019 | Pit | Bradley,A | Traded away | Mia | | After |
| 8/1/2019 | Pit | Lopez,Y | Acquired via trade | Tex | | After |
| 8/1/2019 | Pit | Means | Traded away | Tex | | After |
| 8/1/2019 | SF | Diekman | Traded away | LAA | | After |
| 8/1/2019 | SF | Dyson,J | Traded away | Bos | | After |
| 8/1/2019 | SF | Kluber | Traded away | Bos | | After |
| 8/1/2019 | SF | Luzardo | Acquired via trade | Bos | | After |
| 8/1/2019 | SF | Posey | Traded away | Bos | | After |
| 8/2/2019 | Ari | Burnes | Promoted to active roster | | | Before |
| 8/2/2019 | Ari | Cabrera,G | Demoted to reserve roster | | | Before |
| 8/2/2019 | Ari | Richards,T | Signed | | | Before |
| 8/2/2019 | Ari | Stashak | Released | | | Before |
| 8/2/2019 | ChN | Happ,J | Promoted to active roster | | | Before |
| 8/2/2019 | ChN | Hendriks | Demoted to reserve roster | | | Before |
| 8/2/2019 | ChN | Keuchel | Demoted to reserve roster | | | Before |
| 8/2/2019 | ChN | Minor | Promoted to active roster | | | Before |
| 8/2/2019 | Cin | Mills,A | Promoted to active roster | | | Before |
| 8/2/2019 | Cin | Whitlock | Released | | | Before |
| 8/2/2019 | NYN | Walding | Released | | | Before |
| 8/2/2019 | Pit | Harvey,H | Signed | | | Before |
| 8/2/2019 | Pit | Harvey,H | Promoted to active roster | | | Before |
| 8/2/2019 | Pit | Pineda | Demoted to reserve roster | | | Before |
| 8/2/2019 | Pit | Wood,A | Promoted to active roster | | | Before |
| 8/2/2019 | SF | Cumberland | Signed | | | Before |
| 8/2/2019 | SF | Hanson | Released | | | Before |
| 8/2/2019 | SF | Hernandez,Yo | Signed | | | Before |
| 8/2/2019 | SF | McBride | Released | | | Before |
| 8/2/2019 | SF | Webb,T | Released | | | Before |
| 8/4/2019 | Cin | Neidert | Acquired via trade | Was | | After |
| 8/4/2019 | Cin | Solak | Traded away | Was | | After |
| 8/4/2019 | Cin | Wendelken | Acquired via trade | Was | | After |
| 8/4/2019 | Was | Brosseau | Acquired via trade | Tex | | After |
| 8/4/2019 | Was | Neidert | Traded away | Cin | | After |
| 8/4/2019 | Was | Solak | Acquired via trade | Cin | | After |
| 8/4/2019 | Was | Wendelken | Traded away | Cin | | After |
| 8/5/2019 | ChN | Contreras | Promoted to active roster | | | Before |
| 8/5/2019 | ChN | Gonzalez,Ch | Demoted to reserve roster | | | Before |
| 8/5/2019 | ChN | Hendriks | Promoted to active roster | | | Before |
| 8/5/2019 | ChN | Keuchel | Promoted to active roster | | | Before |
| 8/5/2019 | ChN | Pirela | Demoted to reserve roster | | | Before |
| 8/5/2019 | ChN | Zagunis | Demoted to reserve roster | | | Before |
| 8/5/2019 | Cin | Ervin | Signed | | | Before |
| 8/5/2019 | Cin | Ferguson,D | Promoted to active roster | | | Before |
| 8/5/2019 | Cin | Law,D | Released | | | Before |
| 8/5/2019 | Cin | Neidert | Demoted to reserve roster | | | Before |
| 8/5/2019 | Cin | Olson,T | Demoted to reserve roster | | | Before |
| 8/5/2019 | Cin | Schebler | Demoted to reserve roster | | | Before |
| 8/5/2019 | Cin | Zamora | Promoted to active roster | | | Before |
| 8/5/2019 | LAN | Altavilla | Demoted to reserve roster | | | Before |
| 8/5/2019 | LAN | Beckham,T | Demoted to reserve roster | | | Before |
| 8/5/2019 | LAN | Borucki | Demoted to reserve roster | | | Before |
| 8/5/2019 | LAN | Borucki | Promoted to active roster | | | Before |
| 8/5/2019 | LAN | Castillo,D | Promoted to active roster | | | Before |
| 8/5/2019 | LAN | Piscotty | Promoted to active roster | | | Before |
| 8/5/2019 | LAN | Ryu | Demoted to reserve roster | | | Before |
| 8/5/2019 | LAN | Skoglund | Promoted to active roster | | | Before |
| 8/5/2019 | LAN | Smith,Dw Jr. | Demoted to reserve roster | | | Before |
| 8/5/2019 | LAN | Thaiss | Promoted to active roster | | | Before |
| 8/5/2019 | Mia | Jackson,Al | Demoted to reserve roster | | | Before |
| 8/5/2019 | Mia | Longoria | Promoted to active roster | | | Before |
| 8/5/2019 | Phi | Franklin | Demoted to reserve roster | | | Before |
| 8/5/2019 | Phi | Hamels | Promoted to active roster | | | Before |
| 8/5/2019 | Phi | Hernandez,K | Demoted to reserve roster | | | Before |
| 8/5/2019 | Phi | Miller,Bra | Promoted to active roster | | | Before |
| 8/5/2019 | Phi | Ozuna | Promoted to active roster | | | Before |
| 8/5/2019 | Phi | Sabathia | Demoted to reserve roster | | | Before |
| 8/5/2019 | Pit | Gardner | Promoted to active roster | | | Before |
| 8/5/2019 | Pit | Harvey,H | Released | | | Before |
| 8/5/2019 | Pit | Moncada | Demoted to reserve roster | | | Before |
| 8/5/2019 | Pit | Tomas | Released | | | Before |
| 8/5/2019 | Pit | Webb,T | Signed | | | Before |
| 8/5/2019 | Pit | Webb,T | Promoted to active roster | | | Before |
| 8/5/2019 | Was | Reyes,V | Released | | | Before |
| 8/5/2019 | Was | Solak | Promoted to active roster | | | Before |
| 8/5/2019 | Was | Torrens | Signed | | | Before |
| 8/8/2019 | Cin | Hoyt | Traded away | NYA | | After |
| 8/8/2019 | Cin | Leyba | Acquired via trade | NYA | | After |
| 8/8/2019 | Was | Abreu,A | Acquired via trade | NYA | | After |
| 8/8/2019 | Was | Cave | Traded away | KC | | After |
| 8/8/2019 | Was | Chisholm | Traded away | NYA | | After |
| 8/8/2019 | Was | Senzatela | Traded away | KC | | After |
| 8/8/2019 | Was | Urias,L | Acquired via trade | NYA | | After |
| 8/8/2019 | Was | Yamamoto | Acquired via trade | NYA | | After |
| 8/9/2019 | Ari | Alvarado | Promoted to active roster | | | Before |
| 8/9/2019 | Ari | Bielak | Demoted to reserve roster | | | Before |
| 8/9/2019 | Ari | Nevin | Promoted to active roster | | | Before |
| 8/9/2019 | Ari | Riley | Demoted to reserve roster | | | Before |
| 8/9/2019 | Ari | Widener | Released | | | Before |
| 8/9/2019 | Atl | Stock | Released | | | Before |
| 8/9/2019 | ChN | Gonzalez,Ch | Promoted to active roster | | | Before |
| 8/9/2019 | ChN | Happ,J | Demoted to reserve roster | | | Before |
| 8/9/2019 | ChN | Minor | Demoted to reserve roster | | | Before |
| 8/9/2019 | ChN | Pirela | Promoted to active roster | | | Before |
| 8/9/2019 | Cin | German | Promoted to active roster | | | Before |
| 8/9/2019 | Cin | Law,D | Signed | | | Before |
| 8/9/2019 | Cin | Law,D | Promoted to active roster | | | Before |
| 8/9/2019 | Cin | Lucroy | Signed | | | Before |
| 8/9/2019 | Cin | Mejia,Ad | Released | | | Before |
| 8/9/2019 | Cin | Schebler | Released | | | Before |
| 8/9/2019 | Col | Rojas,M | Released | | | Before |
| 8/9/2019 | Phi | Barlow | Released | | | Before |
| 8/9/2019 | Phi | Garlick | Released | | | Before |
| 8/9/2019 | Pit | Carpenter,M | Promoted to active roster | | | Before |
| 8/9/2019 | Pit | Elias | Signed | | | Before |
| 8/9/2019 | SD | Hembree | Demoted to reserve roster | | | Before |
| 8/9/2019 | Was | Bolt | Promoted to active roster | | | Before |
| 8/9/2019 | Was | Crick | Signed | | | Before |
| 8/9/2019 | Was | Crick | Promoted to active roster | | | Before |
| 8/9/2019 | Was | Hernandez,Elies | Released | | | Before |
| 8/9/2019 | Was | Hernandez,Elies | Signed | | | Before |
| 8/9/2019 | Was | Hultzen | Signed | | | Before |
| 8/9/2019 | Was | Melendez | Demoted to reserve roster | | | Before |
| 8/9/2019 | Was | Tejeda | Demoted to reserve roster | | | Before |
| 8/9/2019 | Was | Wood,H | Signed | | | Before |
| 8/9/2019 | Was | Wood,H | Promoted to active roster | | | Before |
| 8/9/2019 | Was | Yamamoto | Promoted to active roster | | | Before |
| 8/11/2019 | Cin | Gonzalez,Ma | Traded away | Phi | | After |
| 8/11/2019 | Cin | McHugh | Traded away | Mia | | After |
| 8/11/2019 | Cin | Moniak | Acquired via trade | Phi | | After |
| 8/11/2019 | Cin | Ozuna | Acquired via trade | Phi | | After |
| 8/11/2019 | Cin | Peacock | Traded away | Phi | | After |
| 8/11/2019 | Mia | Bauer | Traded away | Pit | | After |
| 8/11/2019 | Mia | McHugh | Acquired via trade | Cin | | After |
| 8/11/2019 | Mia | Moncada | Acquired via trade | Pit | | After |
| 8/11/2019 | Mia | Pineda | Acquired via trade | Pit | | After |
| 8/11/2019 | Phi | Gonzalez,Ma | Acquired via trade | Cin | | After |
| 8/11/2019 | Phi | Moniak | Traded away | Cin | | After |
| 8/11/2019 | Phi | Ozuna | Traded away | Cin | | After |
| 8/11/2019 | Phi | Peacock | Acquired via trade | Cin | | After |
| 8/11/2019 | Pit | Bauer | Acquired via trade | Mia | | After |
| 8/11/2019 | Pit | Moncada | Traded away | Mia | | After |
| 8/11/2019 | Pit | Pineda | Traded away | Mia | | After |
| 8/11/2019 | Pit | Soler | Acquired via trade | Min | | After |
| 8/12/2019 | Ari | Davis,Ja | Signed | | | Before |
| 8/12/2019 | ChN | Contreras | Demoted to reserve roster | | | Before |
| 8/12/2019 | ChN | Happ,J | Promoted to active roster | | | Before |
| 8/12/2019 | ChN | Simmons,A | Demoted to reserve roster | | | Before |
| 8/12/2019 | ChN | Zagunis | Promoted to active roster | | | Before |
| 8/12/2019 | Cin | Gallen | Promoted to active roster | | | Before |
| 8/12/2019 | Cin | Gonzalez,G | Demoted to reserve roster | | | Before |
| 8/12/2019 | Cin | Neidert | Promoted to active roster | | | Before |
| 8/12/2019 | Col | Chafin | Promoted to active roster | | | Before |
| 8/12/2019 | Col | Sherfy | Demoted to reserve roster | | | Before |
| 8/12/2019 | Mia | Alford | Promoted to active roster | | | Before |
| 8/12/2019 | Mia | Guzman,R | Demoted to reserve roster | | | Before |
| 8/12/2019 | Mia | Holder,J | Demoted to reserve roster | | | Before |
| 8/12/2019 | Mia | Jackson,Al | Promoted to active roster | | | Before |
| 8/12/2019 | Mia | Ruiz,K | Demoted to reserve roster | | | Before |
| 8/12/2019 | Phi | Fields,J | Demoted to reserve roster | | | Before |
| 8/12/2019 | Phi | Heaney | Promoted to active roster | | | Before |
| 8/12/2019 | Pit | Harvey,H | Signed | | | Before |
| 8/12/2019 | Pit | O'Day | Released | | | Before |
| 8/12/2019 | Pit | Zimmermann,B | Released | | | Before |
| 8/14/2019 | SD | Kipnis | Promoted to active roster | | | Before |
| 8/14/2019 | SD | Miley | Promoted to active roster | | | Before |
| 8/14/2019 | SD | Varsho | Promoted to active roster | | | Before |
| 8/15/2019 | Cin | Diaz,A | Acquired via trade | Det | | After |
| 8/15/2019 | Cin | Gonzalez,G | Traded away | Det | | After |
| 8/15/2019 | Pit | Cain | Acquired via trade | Min | | After |
| 8/15/2019 | Pit | Kennedy,I | Acquired via trade | Hou | | After |
| 8/15/2019 | Pit | Morton | Acquired via trade | Min | | After |
| 8/15/2019 | Pit | Pinder,Chad | Traded away | Min | | After |
| 8/15/2019 | Pit | Puig | Traded away | Min | | After |
| 8/15/2019 | Pit | Puig | Acquired via trade | Hou | | After |
| 8/15/2019 | Pit | Soler | Traded away | Hou | | After |
| 8/16/2019 | Ari | Murphy,P | Signed | | | Before |
| 8/16/2019 | ChN | Gonzalez,Ch | Demoted to reserve roster | | | Before |
| 8/16/2019 | ChN | Minor | Promoted to active roster | | | Before |
| 8/16/2019 | Cin | Ferguson,D | Demoted to reserve roster | | | Before |
| 8/16/2019 | Cin | Osuna,J | Promoted to active roster | | | Before |
| 8/16/2019 | Pit | Kennedy,I | Demoted to reserve roster | | | Before |
| 8/16/2019 | Pit | LeBlanc,W | Demoted to reserve roster | | | Before |
| 8/16/2019 | Pit | Molina | Promoted to active roster | | | Before |
| 8/16/2019 | Pit | Samardzija | Demoted to reserve roster | | | Before |
| 8/16/2019 | Pit | Smeltzer | Demoted to reserve roster | | | Before |
| 8/16/2019 | Was | Barrera,L | Signed | | | Before |
| 8/16/2019 | Was | Crick | Released | | | Before |
| 8/16/2019 | Was | White,El | Released | | | Before |
| 8/18/2019 | Cin | Almora | Traded away | Was | | After |
| 8/18/2019 | Was | Almora | Acquired via trade | Cin | | After |
| 8/19/2019 | ChN | Dickerson,A | Promoted to active roster | | | Before |
| 8/19/2019 | ChN | Gonzalez,Ch | Promoted to active roster | | | Before |
| 8/19/2019 | ChN | McNeil | Demoted to reserve roster | | | Before |
| 8/19/2019 | ChN | Minor | Demoted to reserve roster | | | Before |
| 8/19/2019 | ChN | Short,Z | Promoted to active roster | | | Before |
| 8/19/2019 | ChN | White,T | Demoted to reserve roster | | | Before |
| 8/19/2019 | NYN | Black,R | Demoted to reserve roster | | | Before |
| 8/19/2019 | NYN | Carroll | Promoted to active roster | | | Before |
| 8/19/2019 | NYN | Norris,B | Demoted to reserve roster | | | Before |
| 8/19/2019 | NYN | Ortiz,L | Promoted to active roster | | | Before |
| 8/19/2019 | NYN | Palumbo | Promoted to active roster | | | Before |
| 8/19/2019 | NYN | Quantrill | Demoted to reserve roster | | | Before |
| 8/19/2019 | NYN | Sandoval,Pab | Promoted to active roster | | | Before |
| 8/19/2019 | NYN | Sipp | Demoted to reserve roster | | | Before |
| 8/19/2019 | Pit | Hernandez,Elies | Signed | | | Before |
| 8/19/2019 | Pit | Kennedy,I | Promoted to active roster | | | Before |
| 8/19/2019 | Pit | Kinsler | Demoted to reserve roster | | | Before |
| 8/19/2019 | Pit | Zimmermann,B | Signed | | | Before |
| 8/19/2019 | Was | Almora | Promoted to active roster | | | Before |
| 8/19/2019 | Was | Stashak | Signed | | | Before |
| 8/19/2019 | Was | Stashak | Promoted to active roster | | | Before |
| 8/21/2019 | Ari | Alvarado | Promoted to active roster | | | Before |
| 8/21/2019 | Ari | Bielak | Demoted to reserve roster | | | Before |
| 8/22/2019 | Mia | Cain | Acquired via trade | Pit | | After |
| 8/22/2019 | Mia | Holder,J | Traded away | Pit | | After |
| 8/22/2019 | Pit | Cain | Traded away | Mia | | After |
| 8/22/2019 | Pit | Holder,J | Acquired via trade | Mia | | After |
| 8/22/2019 | Was | Howard,B | Traded away | Min | | After |
| 8/22/2019 | Was | Tejeda | Traded away | NYA | | After |
| 8/23/2019 | Atl | Garcia,An | Promoted to active roster | | | Before |
| 8/23/2019 | Atl | Mazara | Demoted to reserve roster | | | Before |
| 8/23/2019 | Atl | Pruitt | Promoted to active roster | | | Before |
| 8/23/2019 | ChN | Garlick | Signed | | | Before |
| 8/23/2019 | ChN | Gonzalez,Ch | Demoted to reserve roster | | | Before |
| 8/23/2019 | ChN | Minor | Promoted to active roster | | | Before |
| 8/23/2019 | Mia | Alford | Demoted to reserve roster | | | Before |
| 8/23/2019 | Mia | Longoria | Demoted to reserve roster | | | Before |
| 8/23/2019 | Mia | Moncada | Promoted to active roster | | | Before |
| 8/23/2019 | Was | Medina | Demoted to reserve roster | | | Before |
| 8/23/2019 | Was | Perdomo,L | Signed | | | Before |
| 8/23/2019 | Was | Perdomo,L | Promoted to active roster | | | Before |
| 8/23/2019 | Was | Ramirez,No | Signed | | | Before |
| 8/23/2019 | Was | Ramirez,No | Promoted to active roster | | | Before |
| 8/25/2019 | Mia | Diaz,I | Acquired via trade | Bos | | After |
| 8/25/2019 | Mia | Gausman | Traded away | Bos | | After |
| 8/25/2019 | Mia | Gregorius | Traded away | Bos | | After |
| 8/25/2019 | Mia | Rodriguez,E | Acquired via trade | Bos | | After |
| 8/25/2019 | Pit | Anderson,Bri | Traded away | Bal | | After |
| 8/25/2019 | Pit | Carrasco | Traded away | Bal | | After |
| 8/25/2019 | Pit | Greinke | Acquired via trade | Bal | | After |
| 8/25/2019 | Pit | Moustakas | Acquired via trade | Bal | | After |
| 8/25/2019 | SF | Astudillo | Traded away | Det | | After |
| 8/25/2019 | SF | Duffy,M | Traded away | NYA | | After |
| 8/25/2019 | SF | Shaw,T | Acquired via trade | Det | | After |
| 8/25/2019 | Was | Medina | Traded away | Min | | After |
| 8/25/2019 | Was | Vogelbach | Acquired via trade | Min | | After |
| 8/26/2019 | Ari | O'Day | Signed | | | Before |
| 8/26/2019 | ChN | Brennan | Released | | | Before |
| 8/26/2019 | ChN | Dean,A | Signed | | | Before |
| 8/26/2019 | ChN | Dean,A | Promoted to active roster | | | Before |
| 8/26/2019 | ChN | Dickerson,A | Demoted to reserve roster | | | Before |
| 8/26/2019 | ChN | Gonzalez,Ch | Promoted to active roster | | | Before |
| 8/26/2019 | ChN | Hicklen | Signed | | | Before |
| 8/26/2019 | ChN | Mekkes | Released | | | Before |
| 8/26/2019 | ChN | Minor | Demoted to reserve roster | | | Before |
| 8/26/2019 | ChN | Short,Z | Demoted to reserve roster | | | Before |
| 8/26/2019 | ChN | Simmons,A | Promoted to active roster | | | Before |
| 8/26/2019 | Cin | Ferguson,D | Promoted to active roster | | | Before |
| 8/26/2019 | Cin | Osuna,J | Demoted to reserve roster | | | Before |
| 8/26/2019 | Cin | VanMeter | Promoted to active roster | | | Before |
| 8/26/2019 | Cin | Winker | Demoted to reserve roster | | | Before |
| 8/26/2019 | Mia | Longoria | Promoted to active roster | | | Before |
| 8/26/2019 | Phi | Beaty | Demoted to reserve roster | | | Before |
| 8/26/2019 | Phi | Cervelli | Promoted to active roster | | | Before |
| 8/26/2019 | Phi | Gray,J | Demoted to reserve roster | | | Before |
| 8/26/2019 | Phi | Hernandez,K | Promoted to active roster | | | Before |
| 8/26/2019 | Phi | Iannetta | Demoted to reserve roster | | | Before |
| 8/26/2019 | Phi | Parra,G | Demoted to reserve roster | | | Before |
| 8/26/2019 | Phi | Parra,G | Promoted to active roster | | | Before |
| 8/26/2019 | Phi | Peacock | Promoted to active roster | | | Before |
| 8/26/2019 | Phi | Pivetta | Demoted to reserve roster | | | Before |
| 8/26/2019 | Phi | Pivetta | Promoted to active roster | | | Before |
| 8/26/2019 | Was | Bolt | Demoted to reserve roster | | | Before |
| 8/26/2019 | Was | Brown,Z | Signed | | | Before |
| 8/28/2019 | SD | Archer,C | Demoted to reserve roster | | | Before |
| 8/29/2019 | Ari | Foltynewicz | Traded away | Col | | After |
| 8/29/2019 | Ari | Mahle | Acquired via trade | Col | | After |
| 8/29/2019 | Col | Foltynewicz | Acquired via trade | Ari | | After |
| 8/29/2019 | Col | Mahle | Traded away | Ari | | After |
| 8/30/2019 | Ari | Alvarado | Demoted to reserve roster | | | Before |
| 8/30/2019 | Ari | Loaisiga | Promoted to active roster | | | Before |
| 8/30/2019 | Ari | Mahle | Promoted to active roster | | | Before |
| 8/30/2019 | Atl | Garcia,An | Demoted to reserve roster | | | Before |
| 8/30/2019 | Atl | Swanson,D | Promoted to active roster | | | Before |
| 8/30/2019 | ChN | Gonzalez,Ch | Demoted to reserve roster | | | Before |
| 8/30/2019 | ChN | Minor | Promoted to active roster | | | Before |
| 8/30/2019 | Cin | Grullon | Demoted to reserve roster | | | Before |
| 8/30/2019 | Cin | Grullon | Promoted to active roster | | | Before |
| 8/30/2019 | Cin | Grullon | Promoted to active roster | | | Before |
| 8/30/2019 | Cin | Gutierrez,V | Promoted to active roster | | | Before |
| 8/30/2019 | Cin | Kremer | Promoted to active roster | | | Before |
| 8/30/2019 | Cin | Leake | Demoted to reserve roster | | | Before |
| 8/30/2019 | Cin | Mills,A | Demoted to reserve roster | | | Before |
| 8/30/2019 | Cin | Neidert | Demoted to reserve roster | | | Before |
| 8/30/2019 | Cin | Olson,T | Released | | | Before |
| 8/30/2019 | Cin | Powers | Signed | | | Before |
| 8/30/2019 | Cin | Quiroz | Demoted to reserve roster | | | Before |
| 8/30/2019 | Cin | White,M | Promoted to active roster | | | Before |
| 8/30/2019 | Phi | Melville | Signed | | | Before |
| 8/30/2019 | Pit | Roe | Signed | | | Before |
| 9/1/2019 | LAN | Braun | Traded away | Pit | | After |
| 9/1/2019 | LAN | Lynn | Acquired via trade | Pit | | After |
| 9/1/2019 | LAN | Ottavino | Traded away | Pit | | After |
| 9/1/2019 | Phi | Colome | Acquired via trade | SF | | After |
| 9/1/2019 | Pit | Braun | Acquired via trade | LAN | | After |
| 9/1/2019 | Pit | Doolittle | Acquired via trade | SF | | After |
| 9/1/2019 | Pit | Harrison,M | Traded away | SF | | After |
| 9/1/2019 | Pit | Harrison,M | Acquired via trade | Was | | After |
| 9/1/2019 | Pit | Lynn | Traded away | LAN | | After |
| 9/1/2019 | Pit | Ottavino | Acquired via trade | LAN | | After |
| 9/1/2019 | Pit | Shaw,T | Acquired via trade | SF | | After |
| 9/1/2019 | Pit | Smeltzer | Traded away | Was | | After |
| 9/1/2019 | Pit | Thames | Acquired via trade | SF | | After |
| 9/1/2019 | Pit | Wood,A | Traded away | Was | | After |
| 9/1/2019 | SF | Colome | Traded away | Phi | | After |
| 9/1/2019 | SF | Doolittle | Traded away | Pit | | After |
| 9/1/2019 | SF | Harrison,M | Acquired via trade | Pit | | After |
| 9/1/2019 | SF | Shaw,T | Traded away | Pit | | After |
| 9/1/2019 | SF | Thames | Traded away | Pit | | After |
| 9/1/2019 | Was | Allard | Traded away | Tam | | After |
| 9/1/2019 | Was | Boyd,M | Acquired via trade | Cle | | After |
| 9/1/2019 | Was | Canning | Acquired via trade | Tam | | After |
| 9/1/2019 | Was | Harrison,M | Traded away | Pit | | After |
| 9/1/2019 | Was | Smeltzer | Acquired via trade | Pit | | After |
| 9/1/2019 | Was | Solak | Traded away | Cle | | After |
| 9/1/2019 | Was | Wood,A | Acquired via trade | Pit | | After |
| 9/2/2019 | Ari | Cabrera,G | Promoted to active roster | | | Before |
| 9/2/2019 | Ari | Richards,T | Promoted to active roster | | | Before |
| 9/2/2019 | Ari | Wentz | Promoted to active roster | | | Before |
| 9/2/2019 | ChN | Burke | Promoted to active roster | | | Before |
| 9/2/2019 | ChN | Cronenworth | Promoted to active roster | | | Before |
| 9/2/2019 | ChN | Dickerson,A | Promoted to active roster | | | Before |
| 9/2/2019 | ChN | Garlick | Promoted to active roster | | | Before |
| 9/2/2019 | ChN | Gibaut | Promoted to active roster | | | Before |
| 9/2/2019 | ChN | Gonzalez,Ch | Promoted to active roster | | | Before |
| 9/2/2019 | ChN | Hicklen | Promoted to active roster | | | Before |
| 9/2/2019 | ChN | Kittredge | Promoted to active roster | | | Before |
| 9/2/2019 | ChN | McCurry | Promoted to active roster | | | Before |
| 9/2/2019 | ChN | McNeil | Promoted to active roster | | | Before |
| 9/2/2019 | ChN | Ramirez,Har | Promoted to active roster | | | Before |
| 9/2/2019 | ChN | Short,Z | Promoted to active roster | | | Before |
| 9/2/2019 | Cin | Aquino | Promoted to active roster | | | Before |
| 9/2/2019 | Cin | Diaz,A | Promoted to active roster | | | Before |
| 9/2/2019 | Cin | Diaz,Yu | Promoted to active roster | | | Before |
| 9/2/2019 | Cin | Ervin | Promoted to active roster | | | Before |
| 9/2/2019 | Cin | Leyba | Promoted to active roster | | | Before |
| 9/2/2019 | Cin | Long,S | Promoted to active roster | | | Before |
| 9/2/2019 | Cin | Moniak | Promoted to active roster | | | Before |
| 9/2/2019 | Cin | Osuna,J | Promoted to active roster | | | Before |
| 9/2/2019 | Cin | Powers | Promoted to active roster | | | Before |
| 9/2/2019 | NYN | Buchholz | Demoted to reserve roster | | | Before |
| 9/2/2019 | NYN | Buchholz | Promoted to active roster | | | Before |
| 9/2/2019 | NYN | Davis,JD | Promoted to active roster | | | Before |
| 9/2/2019 | NYN | Hiura | Demoted to reserve roster | | | Before |
| 9/2/2019 | NYN | Jones,No | Promoted to active roster | | | Before |
| 9/2/2019 | NYN | Keller,M | Promoted to active roster | | | Before |
| 9/2/2019 | NYN | Mondesi | Promoted to active roster | | | Before |
| 9/2/2019 | NYN | Ramirez,JE | Demoted to reserve roster | | | Before |
| 9/2/2019 | NYN | Reed,AJ | Promoted to active roster | | | Before |
| 9/2/2019 | NYN | Romero,F | Promoted to active roster | | | Before |
| 9/2/2019 | NYN | Smith,Do | Demoted to reserve roster | | | Before |
| 9/2/2019 | Pit | Kelley,S | Promoted to active roster | | | Before |
| 9/2/2019 | Pit | Roe | Promoted to active roster | | | Before |
| 9/2/2019 | Pit | Shaw,T | Promoted to active roster | | | Before |
| 9/2/2019 | SF | Granderson | Released | | | Before |
| 9/2/2019 | SF | Gyorko | Promoted to active roster | | | Before |
| 9/2/2019 | SF | Reynolds,B | Promoted to active roster | | | Before |
| 9/2/2019 | SF | Sanchez,Y | Promoted to active roster | | | Before |
| 9/2/2019 | Was | Demeritte | Signed | | | Before |
| 9/4/2019 | Phi | Peacock | Demoted to reserve roster | | | Before |
| 9/4/2019 | Pit | Doolittle | Demoted to reserve roster | | | Before |
| 9/6/2019 | ChN | Tapia,R | Demoted to reserve roster | | | Before |
| 9/6/2019 | Cin | Adrianza | Signed | | | Before |
| 9/6/2019 | Cin | Adrianza | Promoted to active roster | | | Before |
| 9/6/2019 | Cin | Bautista,G | Released | | | Before |
| 9/6/2019 | Cin | Law,D | Released | | | Before |
| 9/6/2019 | Cin | Neidert | Promoted to active roster | | | Before |
| 9/6/2019 | Cin | Panik | Demoted to reserve roster | | | Before |
| 9/6/2019 | Cin | Plawecki | Released | | | Before |
| 9/6/2019 | Cin | Stripling | Promoted to active roster | | | Before |
| 9/6/2019 | Cin | Urias,R | Demoted to reserve roster | | | Before |
| 9/6/2019 | Cin | Zeuch | Signed | | | Before |
| 9/6/2019 | Cin | Zeuch | Promoted to active roster | | | Before |
| 9/6/2019 | Col | Chafin | Demoted to reserve roster | | | Before |
| 9/6/2019 | NYN | Hudson,Dan | Signed | | | Before |
| 9/6/2019 | NYN | McBroom | Signed | | | Before |
| 9/6/2019 | NYN | Sipp | Released | | | Before |
| 9/6/2019 | NYN | Span | Released | | | Before |
| 9/6/2019 | Pit | Doolittle | Promoted to active roster | | | Before |
| 9/6/2019 | Pit | Pence | Demoted to reserve roster | | | Before |
| 9/6/2019 | SF | Choi | Released | | | Before |
| 9/6/2019 | SF | Harrison,M | Promoted to active roster | | | Before |
| 9/6/2019 | SF | Luzardo | Promoted to active roster | | | Before |
| 9/6/2019 | SF | Taylor,Cu | Released | | | Before |
| 9/6/2019 | SF | Williams,M | Signed | | | Before |
| 9/6/2019 | Was | Barrett,A | Signed | | | Before |
| 9/6/2019 | Was | Zeuch | Released | | | Before |
| 9/6/2019 | Was | Zeuch | Signed | | | Before |
| 9/9/2019 | Ari | O'Day | Released | | | Before |
| 9/9/2019 | Atl | Cron,K | Demoted to reserve roster | | | Before |
| 9/9/2019 | Atl | Mazara | Promoted to active roster | | | Before |
| 9/9/2019 | Atl | Mercado | Demoted to reserve roster | | | Before |
| 9/9/2019 | Atl | Morrison | Demoted to reserve roster | | | Before |
| 9/9/2019 | Atl | Nimmo | Promoted to active roster | | | Before |
| 9/9/2019 | Atl | Zimmer,B | Promoted to active roster | | | Before |
| 9/9/2019 | ChN | Contreras | Promoted to active roster | | | Before |
| 9/9/2019 | Col | Duggar | Released | | | Before |
| 9/9/2019 | Phi | Beaty | Promoted to active roster | | | Before |
| 9/9/2019 | Phi | Muncy | Demoted to reserve roster | | | Before |
| 9/9/2019 | SF | Buchter | Released | | | Before |
| 9/9/2019 | SF | Desmond | Released | | | Before |
| 9/9/2019 | SF | Hernandez,Yo | Promoted to active roster | | | Before |
| 9/9/2019 | SF | Howard,R | Promoted to active roster | | | Before |
| 9/9/2019 | SF | Lowrie | Promoted to active roster | | | Before |
| 9/9/2019 | SF | Read | Signed | | | Before |
| 9/9/2019 | SF | Sanchez,Y | Released | | | Before |
| 9/13/2019 | Ari | Bielak | Promoted to active roster | | | Before |
| 9/13/2019 | Ari | Burnes | Demoted to reserve roster | | | Before |
| 9/13/2019 | Cin | Adrianza | Released | | | Before |
| 9/13/2019 | Cin | Avilan | Demoted to reserve roster | | | Before |
| 9/13/2019 | Cin | Lucroy | Released | | | Before |
| 9/13/2019 | Cin | Ozuna | Demoted to reserve roster | | | Before |
| 9/15/2019 | Pit | Trout | Demoted to reserve roster | | | Before |
| 9/16/2019 | Ari | Davis,Ja | Promoted to active roster | | | Before |
| 9/16/2019 | Ari | Dunn,J | Promoted to active roster | | | Before |
| 9/16/2019 | Ari | Estevez,C | Signed | | | Before |
| 9/16/2019 | Ari | Murphy,P | Promoted to active roster | | | Before |
| 9/16/2019 | Ari | Riley | Promoted to active roster | | | Before |
| 9/16/2019 | Ari | Supak | Released | | | Before |
| 9/16/2019 | Ari | Ynoa,H | Promoted to active roster | | | Before |
| 9/16/2019 | Atl | Garcia,An | Released | | | Before |
| 9/16/2019 | Atl | Mendick | Signed | | | Before |
| 9/16/2019 | ChN | James,J | Promoted to active roster | | | Before |
| 9/16/2019 | ChN | Tapia,R | Promoted to active roster | | | Before |
| 9/16/2019 | Cin | Adams,M | Demoted to reserve roster | | | Before |
| 9/16/2019 | Cin | Avilan | Released | | | Before |
| 9/16/2019 | Cin | Diaz,A | Demoted to reserve roster | | | Before |
| 9/16/2019 | Cin | Gurriel,L | Promoted to active roster | | | Before |
| 9/16/2019 | Cin | Quiroz | Promoted to active roster | | | Before |
| 9/16/2019 | Mia | Alford | Promoted to active roster | | | Before |
| 9/16/2019 | Mia | Diaz,I | Promoted to active roster | | | Before |
| 9/16/2019 | Mia | Guzman,R | Promoted to active roster | | | Before |
| 9/16/2019 | Mia | Matz | Promoted to active roster | | | Before |
| 9/16/2019 | Mia | McHugh | Demoted to reserve roster | | | Before |
| 9/16/2019 | Mia | Norris,D | Promoted to active roster | | | Before |
| 9/16/2019 | Mia | Rizzo,A | Demoted to reserve roster | | | Before |
| 9/16/2019 | Mia | Ross,J | Promoted to active roster | | | Before |
| 9/16/2019 | Mia | Walden | Promoted to active roster | | | Before |
| 9/20/2019 | Cin | Adams,M | Promoted to active roster | | | Before |
| 9/20/2019 | Cin | Aquino | Demoted to reserve roster | | | Before |
| 9/20/2019 | Cin | Diaz,A | Promoted to active roster | | | Before |
| 9/20/2019 | Cin | Diaz,Yu | Demoted to reserve roster | | | Before |
| 9/20/2019 | Cin | German | Demoted to reserve roster | | | Before |
| 9/20/2019 | Cin | Gurriel,L | Demoted to reserve roster | | | Before |
| 9/20/2019 | Cin | Leake | Promoted to active roster | | | Before |
| 9/20/2019 | Cin | Leyba | Demoted to reserve roster | | | Before |
| 9/20/2019 | Cin | Mills,A | Promoted to active roster | | | Before |
| 9/20/2019 | Cin | Moniak | Demoted to reserve roster | | | Before |
| 9/20/2019 | Cin | Ozuna | Promoted to active roster | | | Before |
| 9/20/2019 | Cin | Panik | Promoted to active roster | | | Before |
| 9/20/2019 | Cin | Urias,R | Promoted to active roster | | | Before |
| 9/20/2019 | Cin | VanMeter | Demoted to reserve roster | | | Before |
| 9/20/2019 | Cin | White,M | Demoted to reserve roster | | | Before |
| 9/20/2019 | Cin | Winker | Demoted to reserve roster | | | Before |
| 9/20/2019 | Cin | Winker | Promoted to active roster | | | Before |
| 9/20/2019 | Cin | Zeuch | Demoted to reserve roster | | | Before |
| 9/20/2019 | Mia | Rizzo,A | Promoted to active roster | | | Before |
| 9/20/2019 | Mia | Stanton | Promoted to active roster | | | Before |
| 9/20/2019 | Was | Crichton | Signed | | | Before |
| 9/20/2019 | Was | Martin,Ri | Signed | | | Before |
| 9/20/2019 | Was | Ramirez,No | Released | | | Before |
| 9/22/2019 | Ari | Santillan | Acquired via trade | Col | | After |
| 9/22/2019 | Col | Santillan | Traded away | Ari | | After |
| 9/23/2019 | ChN | Chirinos,Y | Promoted to active roster | | | Before |
| 9/23/2019 | Col | Chafin | Promoted to active roster | | | Before |
| 9/23/2019 | Col | Chirinos,R | Promoted to active roster | | | Before |
| 9/23/2019 | Col | Duplantier | Promoted to active roster | | | Before |
| 9/23/2019 | Col | Estrada,T | Demoted to reserve roster | | | Before |
| 9/23/2019 | Col | Estrada,T | Promoted to active roster | | | Before |
| 9/23/2019 | Col | Holloway | Released | | | Before |
| 9/23/2019 | Col | Kintzler | Promoted to active roster | | | Before |
| 9/23/2019 | Col | Sherfy | Promoted to active roster | | | Before |
| 9/23/2019 | Col | Treinen | Demoted to reserve roster | | | Before |
| 9/23/2019 | Col | Wong,Ko | Promoted to active roster | | | Before |
| 9/23/2019 | Pit | Hill,R | Promoted to active roster | | | Before |
| 9/27/2019 | ChN | Montas | Promoted to active roster | | | Before |
| 9/27/2019 | ChN | Zagunis | Demoted to reserve roster | | | Before |
| 9/27/2019 | Pit | Bauer | Demoted to reserve roster | | | Before |
| 9/27/2019 | Pit | Doolittle | Demoted to reserve roster | | | Before |
| 9/27/2019 | Pit | Familia | Demoted to reserve roster | | | Before |
| 9/27/2019 | Pit | Greinke | Demoted to reserve roster | | | Before |
| 9/27/2019 | Pit | Harris,W | Demoted to reserve roster | | | Before |
| 9/27/2019 | Pit | Hernandez,Elies | Promoted to active roster | | | Before |
| 9/27/2019 | Pit | Miller,Andr | Demoted to reserve roster | | | Before |
| 9/27/2019 | Pit | Molina | Demoted to reserve roster | | | Before |
| 9/27/2019 | Pit | Morton | Demoted to reserve roster | | | Before |
| 9/27/2019 | Pit | Ottavino | Demoted to reserve roster | | | Before |
| 9/27/2019 | StL | Mayers | Released | | | Before |
