| Transactions |
| Date | Team | Player | Type | OthTm | EffDate | When |
| 3/30/2010 | DLM | Hundley | Promoted to active roster | | | Before |
| 3/30/2010 | GAR | Ankiel | Placed on Injured List | | 3/30/2010 | Before |
| 3/30/2010 | GAR | Ludwick | Promoted to active roster | | | Before |
| 3/31/2010 | CIN | Ciriaco | Demoted to reserve roster | | | Before |
| 3/31/2010 | CIN | Ramirez,Al | Promoted to active roster | | | Before |
| 3/31/2010 | DLM | Lucroy | Placed on Injured List | | 3/30/2010 | Before |
| 3/31/2010 | TEW | Buchholz,T | Promoted to active roster | | | Before |
| 3/31/2010 | TEW | Moscoso | Demoted to reserve roster | | | Before |
| 4/1/2010 | CTW | Carmona | Demoted to reserve roster | | | Before |
| 4/1/2010 | CTW | Chacin,J | Promoted to active roster | | | Before |
| 4/3/2010 | CIN | Trumbo | Demoted to reserve roster | | | Before |
| 4/3/2010 | CIN | Willingham | Promoted to active roster | | | Before |
| 4/4/2010 | DLM | Podsednik | Promoted to active roster | | | Before |
| 4/4/2010 | DLM | Span | Placed on Injured List | | 4/1/2010 | Before |
| 4/7/2010 | DLM | DeWitt | Demoted to reserve roster | | | Before |
| 4/7/2010 | DLM | Redmond | Promoted to active roster | | | Before |
| 4/7/2010 | GAR | Barmes | Placed on Injured List | | 4/7/2010 | Before |
| 4/7/2010 | GAR | Grudzielanek | Promoted to active roster | | | Before |
| 4/8/2010 | CIN | Freeman | Demoted to reserve roster | | | Before |
| 4/8/2010 | CIN | Kottaras | Promoted to active roster | | | Before |
| 4/9/2010 | CSS | Cishek | Demoted to reserve roster | | | Before |
| 4/9/2010 | CSS | Jeffress | Promoted to active roster | | | Before |
| 4/10/2010 | DLM | DeWitt | Promoted to active roster | | | Before |
| 4/10/2010 | DLM | Hundley | Demoted to reserve roster | | | Before |
| 4/10/2010 | GAR | Arrieta | Placed on Injured List | | 4/10/2010 | Before |
| 4/10/2010 | GAR | Wakefield | Promoted to active roster | | | Before |
| 4/11/2010 | BRK | Braddock | Promoted to active roster | | | Before |
| 4/11/2010 | BRK | Lilly | Placed on Injured List | | 4/9/2010 | Before |
| 4/11/2010 | BRK | Pagnozzi | Demoted to reserve roster | | | Before |
| 4/11/2010 | BRK | Worley | Promoted to active roster | | | Before |
| 4/11/2010 | CIN | Arencibia | Demoted to reserve roster | | | Before |
| 4/11/2010 | CIN | Jennings | Demoted to reserve roster | | | Before |
| 4/11/2010 | CIN | Pena,B | Promoted to active roster | | | Before |
| 4/11/2010 | CIN | Young,E | Promoted to active roster | | | Before |
| 4/13/2010 | GAR | Grudzielanek | Demoted to reserve roster | | | Before |
| 4/13/2010 | GAR | Wigginton | Promoted to active roster | | | Before |
| 4/14/2010 | DLM | Pestano | Demoted to reserve roster | | | Before |
| 4/15/2010 | BBG | Harrison | Promoted to active roster | | | Before |
| 4/15/2010 | BBG | Johnson,Jo | Placed on Injured List | | 4/15/2010 | Before |
| 4/15/2010 | GAR | Bradley | Promoted to active roster | | | Before |
| 4/15/2010 | GAR | Dyson | Demoted to reserve roster | | | Before |
| 4/16/2010 | AST | Wilson,Jo | Demoted to reserve roster | | | Before |
| 4/16/2010 | AST | Wilson,Jo | Promoted to active roster | | | Before |
| 4/16/2010 | TEW | Hudson,O | Placed on Injured List | | 4/16/2010 | Before |
| 4/16/2010 | TEW | Mora | Promoted to active roster | | | Before |
| 4/17/2010 | BBG | Hanigan | Placed on Injured List | | 4/17/2010 | Before |
| 4/17/2010 | BBG | Olivo | Promoted to active roster | | | Before |
| 4/17/2010 | CIN | Miller,C | Promoted to active roster | | | Before |
| 4/17/2010 | CIN | Saltalamacchia | Demoted to reserve roster | | | Before |
| 4/17/2010 | CSS | Marcum | Demoted to reserve roster | | | Before |
| 4/17/2010 | CSS | Smith,Joe | Promoted to active roster | | | Before |
| 4/18/2010 | CSS | Flowers | Demoted to reserve roster | | | Before |
| 4/18/2010 | CSS | Posada | Promoted to active roster | | | Before |
| 4/18/2010 | CTW | Kuo | Placed on Injured List | | 4/18/2010 | Before |
| 4/18/2010 | CTW | Lopez,W | Promoted to active roster | | | Before |
| 4/18/2010 | GAR | McKenry | Demoted to reserve roster | | | Before |
| 4/18/2010 | GAR | Snyder,C | Promoted to active roster | | | Before |
| 4/18/2010 | NEP | Jaso | Placed on Injured List | | 4/18/2010 | Before |
| 4/18/2010 | NEP | Kratz | Promoted to active roster | | | Before |
| 4/18/2010 | NYD | Reynolds,Mat | Promoted to active roster | | | Before |
| 4/18/2010 | NYD | Threets | Demoted to reserve roster | | | Before |
| 4/20/2010 | BBG | De Aza | Promoted to active roster | | | Before |
| 4/20/2010 | BBG | Mayberry | Demoted to reserve roster | | | Before |
| 4/20/2010 | CTW | Joyce | Promoted to active roster | | | Before |
| 4/20/2010 | CTW | Venable | Placed on Injured List | | 4/19/2010 | Before |
| 4/21/2010 | CBB | Chapman | Demoted to reserve roster | | | Before |
| 4/21/2010 | CIO | Casilla,A | Placed on Injured List | | 4/21/2010 | Before |
| 4/21/2010 | CIO | Tolleson | Promoted to active roster | | | Before |
| 4/21/2010 | NYD | Budde | Demoted to reserve roster | | | Before |
| 4/21/2010 | NYD | Zaun | Promoted to active roster | | | Before |
| 4/22/2010 | CIN | Frieri | Promoted to active roster | | | Before |
| 4/22/2010 | CIN | Miller,A | Demoted to reserve roster | | | Before |
| 4/22/2010 | CIO | Maine,J | Released | | | Before |
| 4/22/2010 | CIO | Maine,S | Signed | | | Before |
| 4/22/2010 | CSS | Jackson,E | Promoted to active roster | | | Before |
| 4/22/2010 | CSS | Smith,Joe | Demoted to reserve roster | | | Before |
| 4/22/2010 | SOI | Andino | Promoted to active roster | | | Before |
| 4/22/2010 | SOI | Espinosa | Demoted to reserve roster | | | Before |
| 4/23/2010 | AST | Hairston,S | Promoted to active roster | | | Before |
| 4/23/2010 | AST | Lowrie | Placed on Injured List | | 4/23/2010 | Before |
| 4/23/2010 | AST | Lugo | Promoted to active roster | | | Before |
| 4/23/2010 | AST | Soriano,A | Demoted to reserve roster | | | Before |
| 4/23/2010 | CIO | Maine,S | Demoted to reserve roster | | | Before |
| 4/23/2010 | TEW | Doumit | Placed on Injured List | | 4/23/2010 | Before |
| 4/23/2010 | TEW | Thole | Promoted to active roster | | | Before |
| 4/24/2010 | CSS | Putz | Demoted to reserve roster | | | Before |
| 4/24/2010 | CSS | Smith,Joe | Promoted to active roster | | | Before |
| 4/25/2010 | AST | Bush | Promoted to active roster | | | Before |
| 4/25/2010 | AST | Wright,J | Demoted to reserve roster | | | Before |
| 4/26/2010 | BRK | Heisey | Promoted to active roster | | | Before |
| 4/26/2010 | BRK | Worley | Demoted to reserve roster | | | Before |
| 4/26/2010 | HAR | Rowland-Smith | Promoted to active roster | | | Before |
| 4/26/2010 | HAR | Zimmermann | Demoted to reserve roster | | | Before |
| 4/27/2010 | CIO | Acosta | Demoted to reserve roster | | | Before |
| 4/27/2010 | CIO | Duncan | Demoted to reserve roster | | | Before |
| 4/27/2010 | CIO | Hudson,D | Promoted to active roster | | | Before |
| 4/27/2010 | CIO | Liriano | Demoted to reserve roster | | | Before |
| 4/27/2010 | CIO | Maine,S | Promoted to active roster | | | Before |
| 4/27/2010 | CIO | Wells,C | Promoted to active roster | | | Before |
| 4/27/2010 | DLM | Lucroy | Activated from Injured List | | | Before |
| 4/27/2010 | DLM | O'Flaherty | Placed on Injured List | | 4/27/2010 | Before |
| 4/27/2010 | DLM | Rapada | Promoted to active roster | | | Before |
| 4/27/2010 | DLM | Redmond | Demoted to reserve roster | | | Before |
| 4/27/2010 | NEP | Belisario | Placed on Injured List | | 4/27/2010 | Before |
| 4/27/2010 | NEP | Harrell | Promoted to active roster | | | Before |
| 4/27/2010 | NYD | Gee | Demoted to reserve roster | | | Before |
| 4/27/2010 | NYD | Jenks | Promoted to active roster | | | Before |
| 4/28/2010 | CBB | Niemann | Demoted to reserve roster | | | Before |
| 4/28/2010 | CBB | Tatum | Promoted to active roster | | | Before |
| 4/30/2010 | BRK | DeJesus | Demoted to reserve roster | | | Before |
| 4/30/2010 | BRK | Lilly | Activated from Injured List | | | Before |
| 4/30/2010 | CBB | Niemann | Promoted to active roster | | | Before |
| 4/30/2010 | CBB | Tatum | Demoted to reserve roster | | | Before |
| 4/30/2010 | FDH | Cervelli | Promoted to active roster | | | Before |
| 4/30/2010 | FDH | Ellis,AJ | Demoted to reserve roster | | | Before |
| 4/30/2010 | RMO | Colome | Demoted to reserve roster | | | Before |
| 4/30/2010 | RMO | Nova | Demoted to reserve roster | | | Before |
| 4/30/2010 | RMO | Rodriguez,FJ | Promoted to active roster | | | Before |
| 4/30/2010 | RMO | Tillman | Promoted to active roster | | | Before |
| 4/30/2010 | SOI | de la Rosa | Placed on Injured List | | 4/30/2010 | Before |
| 4/30/2010 | SOI | Hellickson | Demoted to reserve roster | | | Before |
| 4/30/2010 | SOI | McDonald,Ja | Promoted to active roster | | | Before |
| 4/30/2010 | SOI | Paulino,F | Promoted to active roster | | | Before |
| 5/1/2010 | DLM | Pineiro | Promoted to active roster | | | Before |
| 5/1/2010 | GAR | Gload | Promoted to active roster | | | Before |
| 5/1/2010 | GAR | Hoffman | Promoted to active roster | | | Before |
| 5/1/2010 | GAR | Manship | Demoted to reserve roster | | | Before |
| 5/1/2010 | GAR | Stairs | Demoted to reserve roster | | | Before |
| 5/3/2010 | AST | Donaldson | Demoted to reserve roster | | | Before |
| 5/3/2010 | AST | Sardinha | Promoted to active roster | | | Before |
| 5/3/2010 | CIO | Dickey | Placed on Injured List | | 5/3/2010 | Before |
| 5/3/2010 | CIO | Liriano | Promoted to active roster | | | Before |
| 5/3/2010 | CTW | Medlen | Promoted to active roster | | | Before |
| 5/3/2010 | CTW | Stauffer | Placed on Injured List | | 5/3/2010 | Before |
| 5/3/2010 | GAR | Barmes | Activated from Injured List | | | Before |
| 5/3/2010 | GAR | Gload | Placed on Injured List | | 5/3/2010 | Before |
| 5/3/2010 | GAR | Gomes | Promoted to active roster | | | Before |
| 5/3/2010 | GAR | Wigginton | Demoted to reserve roster | | | Before |
| 5/5/2010 | BAR | Mazzaro | Promoted to active roster | | | Before |
| 5/5/2010 | BAR | Minor | Demoted to reserve roster | | | Before |
| 5/5/2010 | CTW | Venable | Activated from Injured List | | | Before |
| 5/5/2010 | CTW | Young,Delm | Demoted to reserve roster | | | Before |
| 5/5/2010 | DLM | Podsednik | Placed on Injured List | | 5/4/2010 | Before |
| 5/5/2010 | DLM | Span | Activated from Injured List | | | Before |
| 5/5/2010 | NEP | Jaso | Activated from Injured List | | | Before |
| 5/5/2010 | NEP | Kratz | Demoted to reserve roster | | | Before |
| 5/7/2010 | CSS | Baker,S | Demoted to reserve roster | | | Before |
| 5/7/2010 | CSS | Helms | Promoted to active roster | | | Before |
| 5/7/2010 | CSS | Hinske | Demoted to reserve roster | | | Before |
| 5/7/2010 | CSS | Thompson,R | Promoted to active roster | | | Before |
| 5/7/2010 | HAR | Carp | Promoted to active roster | | | Before |
| 5/7/2010 | HAR | Chavez,J | Promoted to active roster | | | Before |
| 5/7/2010 | HAR | Davis,C | Demoted to reserve roster | | | Before |
| 5/7/2010 | HAR | Feliz,P | Promoted to active roster | | | Before |
| 5/7/2010 | HAR | Gentry | Demoted to reserve roster | | | Before |
| 5/7/2010 | HAR | Kintzler | Promoted to active roster | | | Before |
| 5/7/2010 | HAR | Melancon | Demoted to reserve roster | | | Before |
| 5/7/2010 | HAR | Ottavino | Promoted to active roster | | | Before |
| 5/7/2010 | HAR | Samardzija | Demoted to reserve roster | | | Before |
| 5/7/2010 | HAR | Strop | Demoted to reserve roster | | | Before |
| 5/8/2010 | TEW | Doumit | Activated from Injured List | | | Before |
| 5/8/2010 | TEW | Thole | Demoted to reserve roster | | | Before |
| 5/9/2010 | ATM | Atchison | Promoted to active roster | | | Before |
| 5/9/2010 | ATM | Rodriguez,W | Promoted to active roster | | | Before |
| 5/9/2010 | ATM | Street | Demoted to reserve roster | | | Before |
| 5/9/2010 | ATM | Westbrook | Demoted to reserve roster | | | Before |
| 5/9/2010 | BAR | Abad | Demoted to reserve roster | | | Before |
| 5/9/2010 | BAR | Lindstrom | Promoted to active roster | | | Before |
| 5/9/2010 | BBG | Hanigan | Activated from Injured List | | | Before |
| 5/9/2010 | BBG | Harrison | Demoted to reserve roster | | | Before |
| 5/9/2010 | BBG | Jansen | Demoted to reserve roster | | | Before |
| 5/9/2010 | BBG | Oliver,D | Promoted to active roster | | | Before |
| 5/9/2010 | BBG | Olivo | Demoted to reserve roster | | | Before |
| 5/10/2010 | AST | Bush | Demoted to reserve roster | | | Before |
| 5/10/2010 | AST | Soriano,A | Promoted to active roster | | | Before |
| 5/10/2010 | BBG | Johnson,Jo | Activated from Injured List | | | Before |
| 5/10/2010 | GAR | Arrieta | Activated from Injured List | | | Before |
| 5/10/2010 | GAR | Moyer | Demoted to reserve roster | | | Before |
| 5/10/2010 | TEW | Hudson,O | Activated from Injured List | | | Before |
| 5/10/2010 | TEW | Mora | Demoted to reserve roster | | | Before |
| 5/11/2010 | CIN | Elbert | Promoted to active roster | | | Before |
| 5/11/2010 | CIN | Frieri | Demoted to reserve roster | | | Before |
| 5/11/2010 | CIN | LeCure | Demoted to reserve roster | | | Before |
| 5/11/2010 | CIN | Logan | Promoted to active roster | | | Before |
| 5/11/2010 | CIN | Perez,C | Promoted to active roster | | | Before |
| 5/11/2010 | CIN | Perez,O | Demoted to reserve roster | | | Before |
| 5/11/2010 | CIN | Simon | Demoted to reserve roster | | | Before |
| 5/11/2010 | CIN | Villanueva | Promoted to active roster | | | Before |
| 5/11/2010 | CSS | Jeffress | Demoted to reserve roster | | | Before |
| 5/11/2010 | CSS | Marcum | Promoted to active roster | | | Before |
| 5/12/2010 | BBG | De Aza | Demoted to reserve roster | | | Before |
| 5/12/2010 | BBG | Downs,M | Promoted to active roster | | | Before |
| 5/12/2010 | DLM | Norberto | Demoted to reserve roster | | | Before |
| 5/12/2010 | GAR | Ankiel | Activated from Injured List | | | Before |
| 5/12/2010 | GAR | Ludwick | Demoted to reserve roster | | | Before |
| 5/13/2010 | DLM | Happ | Promoted to active roster | | | Before |
| 5/13/2010 | DLM | Miller,T | Promoted to active roster | | | Before |
| 5/13/2010 | DLM | Rapada | Demoted to reserve roster | | | Before |
| 5/13/2010 | NEP | Belisario | Activated from Injured List | | | Before |
| 5/13/2010 | NEP | Harrell | Demoted to reserve roster | | | Before |
| 5/14/2010 | CIN | Cordero,F | Promoted to active roster | | | Before |
| 5/14/2010 | CIN | Elbert | Demoted to reserve roster | | | Before |
| 5/14/2010 | CIN | Miller,A | Promoted to active roster | | | Before |
| 5/14/2010 | CIN | Perkins | Demoted to reserve roster | | | Before |
| 5/14/2010 | CTW | Kuo | Activated from Injured List | | | Before |
| 5/14/2010 | CTW | Medlen | Demoted to reserve roster | | | Before |
| 5/14/2010 | DLM | Lopez,R | Promoted to active roster | | | Before |
| 5/14/2010 | DLM | Pineiro | Placed on Injured List | | 5/14/2010 | Before |
| 5/14/2010 | FDH | Stammen | Promoted to active roster | | | Before |
| 5/14/2010 | FDH | Strasburg | Demoted to reserve roster | | | Before |
| 5/15/2010 | CIN | Miller,C | Demoted to reserve roster | | | Before |
| 5/15/2010 | CIN | Valbuena | Promoted to active roster | | | Before |
| 5/15/2010 | FDH | Parnell | Promoted to active roster | | | Before |
| 5/15/2010 | FDH | Salas | Demoted to reserve roster | | | Before |
| 5/15/2010 | HAR | Ambriz | Promoted to active roster | | | Before |
| 5/15/2010 | HAR | Sale | Demoted to reserve roster | | | Before |
| 5/15/2010 | SOI | Longoria | Placed on Injured List | | 5/14/2010 | Before |
| 5/15/2010 | SOI | Varitek | Promoted to active roster | | | Before |
| 5/16/2010 | CBB | Braden | Promoted to active roster | | | Before |
| 5/16/2010 | CBB | Kershaw | Placed on Injured List | | 5/12/2010 | Before |
| 5/17/2010 | FDH | Tomlin | Promoted to active roster | | | Before |
| 5/17/2010 | FDH | Vazquez | Placed on Injured List | | 5/17/2010 | Before |
| 5/17/2010 | GAR | Neshek | Promoted to active roster | | | Before |
| 5/17/2010 | GAR | Ross,T | Demoted to reserve roster | | | Before |
| 5/18/2010 | CIO | Dickey | Activated from Injured List | | | Before |
| 5/18/2010 | CIO | Liriano | Demoted to reserve roster | | | Before |
| 5/19/2010 | CEN | Furcal | Placed on Injured List | | 5/19/2010 | Before |
| 5/19/2010 | CEN | Izturis,M | Promoted to active roster | | | Before |
| 5/19/2010 | CSS | Conrad | Promoted to active roster | | | Before |
| 5/19/2010 | CSS | Utley | Placed on Injured List | | 5/19/2010 | Before |
| 5/21/2010 | AST | Craig | Demoted to reserve roster | | | Before |
| 5/21/2010 | AST | Lowrie | Activated from Injured List | | | Before |
| 5/21/2010 | CEN | Carlin | Promoted to active roster | | | Before |
| 5/21/2010 | CEN | Molina,Y | Placed on Injured List | | 5/20/2010 | Before |
| 5/21/2010 | FDH | Bailey,H | Promoted to active roster | | | Before |
| 5/21/2010 | FDH | Cash | Promoted to active roster | | | Before |
| 5/21/2010 | FDH | Parnell | Demoted to reserve roster | | | Before |
| 5/21/2010 | FDH | Ramos,W | Demoted to reserve roster | | | Before |
| 5/21/2010 | NYD | Reynolds,Mat | Demoted to reserve roster | | | Before |
| 5/21/2010 | NYD | Schlichting | Promoted to active roster | | | Before |
| 5/21/2010 | TEW | Cunningham | Demoted to reserve roster | | | Before |
| 5/21/2010 | TEW | Francisco,B | Promoted to active roster | | | Before |
| 5/22/2010 | BAR | Bourjos | Demoted to reserve roster | | | Before |
| 5/22/2010 | BAR | Francoeur | Placed on Injured List | | 5/22/2010 | Before |
| 5/22/2010 | BAR | Kelley | Promoted to active roster | | | Before |
| 5/22/2010 | BAR | Wise | Promoted to active roster | | | Before |
| 5/22/2010 | BRK | Heisey | Demoted to reserve roster | | | Before |
| 5/22/2010 | BRK | Jones,An | Promoted to active roster | | | Before |
| 5/22/2010 | BRK | Molina,J | Placed on Injured List | | 5/22/2010 | Before |
| 5/22/2010 | BRK | Schneider | Promoted to active roster | | | Before |
| 5/22/2010 | NEP | Jurrjens | Placed on Injured List | | 5/22/2010 | Before |
| 5/22/2010 | NEP | Matusz | Promoted to active roster | | | Before |
| 5/23/2010 | BBG | Harrison | Promoted to active roster | | | Before |
| 5/23/2010 | BBG | Lewis,C | Placed on Injured List | | 5/22/2010 | Before |
| 5/23/2010 | CIO | Acosta | Promoted to active roster | | | Before |
| 5/23/2010 | CIO | Maine,S | Demoted to reserve roster | | | Before |
| 5/23/2010 | CSS | Putz | Promoted to active roster | | | Before |
| 5/23/2010 | CSS | Smith,Joe | Demoted to reserve roster | | | Before |
| 5/23/2010 | HAR | Bonderman | Promoted to active roster | | | Before |
| 5/23/2010 | HAR | Holland,D | Demoted to reserve roster | | | Before |
| 5/24/2010 | CIN | Cordero,F | Demoted to reserve roster | | | Before |
| 5/24/2010 | CIN | Frieri | Promoted to active roster | | | Before |
| 5/26/2010 | DLM | DeWitt | Demoted to reserve roster | | | Before |
| 5/26/2010 | DLM | Hundley | Promoted to active roster | | | Before |
| 5/27/2010 | CBB | Braden | Demoted to reserve roster | | | Before |
| 5/27/2010 | CBB | Kershaw | Activated from Injured List | | | Before |
| 5/27/2010 | HAR | Kintzler | Demoted to reserve roster | | | Before |
| 5/27/2010 | HAR | Kotsay | Promoted to active roster | | | Before |
| 5/27/2010 | NEP | McGehee | Demoted to reserve roster | | | Before |
| 5/27/2010 | NEP | Viciedo | Promoted to active roster | | | Before |
| 5/28/2010 | CEN | Deduno | Promoted to active roster | | | Before |
| 5/28/2010 | CEN | Floyd | Placed on Injured List | | 5/28/2010 | Before |
| 5/28/2010 | CIN | Perez,O | Promoted to active roster | | | Before |
| 5/28/2010 | CIN | Pettitte | Placed on Injured List | | 5/28/2010 | Before |
| 5/28/2010 | CIO | Cousins | Promoted to active roster | | | Before |
| 5/28/2010 | CIO | Morel | Promoted to active roster | | | Before |
| 5/28/2010 | CIO | Rodriguez,A | Demoted to reserve roster | | | Before |
| 5/28/2010 | CIO | Scott | Placed on Injured List | | 5/28/2010 | Before |
| 5/28/2010 | CTW | Hammel | Demoted to reserve roster | | | Before |
| 5/28/2010 | CTW | Stauffer | Activated from Injured List | | | Before |
| 5/29/2010 | CEN | Bard,J | Promoted to active roster | | | Before |
| 5/29/2010 | CEN | Carlin | Demoted to reserve roster | | | Before |
| 5/29/2010 | CIO | Hudson,D | Demoted to reserve roster | | | Before |
| 5/29/2010 | CIO | Liriano | Promoted to active roster | | | Before |
| 5/29/2010 | FDH | Bailey,H | Demoted to reserve roster | | | Before |
| 5/29/2010 | FDH | Beachy | Promoted to active roster | | | Before |
| 5/29/2010 | FDH | Burton | Promoted to active roster | | | Before |
| 5/29/2010 | FDH | Uehara | Demoted to reserve roster | | | Before |
| 5/29/2010 | GAR | Gload | Activated from Injured List | | | Before |
| 5/29/2010 | GAR | Wallace | Placed on Injured List | | 5/29/2010 | Before |
| 5/29/2010 | NYD | Fontenot | Demoted to reserve roster | | | Before |
| 5/29/2010 | NYD | Whiteside | Promoted to active roster | | | Before |
| 5/29/2010 | SOI | Longoria | Activated from Injured List | | | Before |
| 5/29/2010 | SOI | Varitek | Demoted to reserve roster | | | Before |
| 5/29/2010 | TEW | Escobar,Y | Placed on Injured List | | 5/29/2010 | Before |
| 5/29/2010 | TEW | Guzman | Promoted to active roster | | | Before |
| 5/30/2010 | AST | Aybar,E | Demoted to reserve roster | | | Before |
| 5/30/2010 | AST | Belliard | Promoted to active roster | | | Before |
| 5/30/2010 | AST | Castillo,W | Placed on Injured List | | 5/29/2010 | Before |
| 5/30/2010 | AST | Lind | Placed on Injured List | | 5/27/2010 | Before |
| 5/30/2010 | AST | Punto | Promoted to active roster | | | Before |
| 5/30/2010 | AST | Wood,Br | Promoted to active roster | | | Before |
| 5/30/2010 | CEN | Deduno | Demoted to reserve roster | | | Before |
| 5/30/2010 | CEN | Dunn,M | Promoted to active roster | | | Before |
| 5/31/2010 | HAR | Cabrera,O | Promoted to active roster | | | Before |
| 5/31/2010 | HAR | Pearce | Demoted to reserve roster | | | Before |
| 5/31/2010 | TEW | Buchholz,T | Demoted to reserve roster | | | Before |
| 5/31/2010 | TEW | Hernandez,Da | Promoted to active roster | | | Before |
| 6/1/2010 | AST | Bush | Promoted to active roster | | | Before |
| 6/1/2010 | AST | Davies | Demoted to reserve roster | | | Before |
| 6/1/2010 | AST | Norris | Placed on Injured List | | 6/1/2010 | Before |
| 6/1/2010 | AST | Richard | Promoted to active roster | | | Before |
| 6/1/2010 | FDH | Carrasco,C | Demoted to reserve roster | | | Before |
| 6/1/2010 | FDH | Parnell | Promoted to active roster | | | Before |
| 6/2/2010 | CSS | Brantley | Demoted to reserve roster | | | Before |
| 6/2/2010 | CSS | Cain,L | Promoted to active roster | | | Before |
| 6/3/2010 | CSS | Smith,Joe | Promoted to active roster | | | Before |
| 6/3/2010 | CSS | Thompson,R | Demoted to reserve roster | | | Before |
| 6/5/2010 | AST | Sardinha | Demoted to reserve roster | | | Before |
| 6/5/2010 | AST | Teagarden | Promoted to active roster | | | Before |
| 6/5/2010 | ATM | Branyan | Promoted to active roster | | | Before |
| 6/5/2010 | ATM | Morneau | Demoted to reserve roster | | | Before |
| 6/5/2010 | ATM | Nolasco | Demoted to reserve roster | | | Before |
| 6/5/2010 | ATM | Westbrook | Promoted to active roster | | | Before |
| 6/5/2010 | CEN | Castro,R | Demoted to reserve roster | | | Before |
| 6/5/2010 | CEN | Molina,Y | Activated from Injured List | | | Before |
| 6/5/2010 | CTW | Hammel | Promoted to active roster | | | Before |
| 6/5/2010 | CTW | Medlen | Promoted to active roster | | | Before |
| 6/5/2010 | CTW | O'Day | Demoted to reserve roster | | | Before |
| 6/5/2010 | CTW | Stauffer | Demoted to reserve roster | | | Before |
| 6/5/2010 | GAR | Crain | Promoted to active roster | | | Before |
| 6/5/2010 | GAR | Park | Demoted to reserve roster | | | Before |
| 6/6/2010 | BBG | Harrison | Demoted to reserve roster | | | Before |
| 6/6/2010 | BBG | Lewis,C | Activated from Injured List | | | Before |
| 6/6/2010 | BRK | Molina,J | Activated from Injured List | | | Before |
| 6/6/2010 | BRK | Schneider | Demoted to reserve roster | | | Before |
| 6/6/2010 | CIO | Edmonds | Placed on Injured List | | 6/6/2010 | Before |
| 6/6/2010 | CIO | Petersen | Promoted to active roster | | | Before |
| 6/6/2010 | CIO | Rodriguez,A | Promoted to active roster | | | Before |
| 6/6/2010 | CIO | Tolleson | Demoted to reserve roster | | | Before |
| 6/6/2010 | GAR | Madson | Demoted to reserve roster | | | Before |
| 6/6/2010 | GAR | McGee | Promoted to active roster | | | Before |
| 6/6/2010 | NEP | Hunter,Tom | Demoted to reserve roster | | | Before |
| 6/6/2010 | NEP | Jurrjens | Activated from Injured List | | | Before |
| 6/7/2010 | AST | Aybar,E | Promoted to active roster | | | Before |
| 6/7/2010 | AST | Lowrie | Demoted to reserve roster | | | Before |
| 6/7/2010 | CSS | Baker,S | Promoted to active roster | | | Before |
| 6/7/2010 | CSS | Buehrle | Demoted to reserve roster | | | Before |
| 6/8/2010 | CSS | Axford | Demoted to reserve roster | | | Before |
| 6/8/2010 | CSS | Lopez,Ja | Demoted to reserve roster | | | Before |
| 6/8/2010 | CSS | Marte,D | Promoted to active roster | | | Before |
| 6/8/2010 | CSS | Moylan | Demoted to reserve roster | | | Before |
| 6/8/2010 | CSS | Romero,JC | Promoted to active roster | | | Before |
| 6/8/2010 | CSS | Webb | Promoted to active roster | | | Before |
| 6/8/2010 | FDH | Burton | Demoted to reserve roster | | | Before |
| 6/8/2010 | FDH | Vazquez | Activated from Injured List | | | Before |
| 6/9/2010 | AST | Davies | Promoted to active roster | | | Before |
| 6/9/2010 | AST | O'Sullivan | Promoted to active roster | | | Before |
| 6/9/2010 | AST | Ogando | Demoted to reserve roster | | | Before |
| 6/9/2010 | AST | Richard | Demoted to reserve roster | | | Before |
| 6/9/2010 | BAR | Francoeur | Activated from Injured List | | | Before |
| 6/9/2010 | BAR | Wise | Demoted to reserve roster | | | Before |
| 6/9/2010 | BBG | Aceves | Promoted to active roster | | | Before |
| 6/9/2010 | BBG | Peralta,Jo | Demoted to reserve roster | | | Before |
| 6/9/2010 | CIN | Cordero,F | Promoted to active roster | | | Before |
| 6/9/2010 | CIN | Miller,A | Demoted to reserve roster | | | Before |
| 6/9/2010 | CSS | Blanco,G | Promoted to active roster | | | Before |
| 6/9/2010 | CSS | Hart | Placed on Injured List | | 6/6/2010 | Before |
| 6/9/2010 | NYD | Ekstrom | Promoted to active roster | | | Before |
| 6/9/2010 | NYD | Farnsworth | Placed on Injured List | | 6/9/2010 | Before |
| 6/9/2010 | NYD | Fontenot | Promoted to active roster | | | Before |
| 6/9/2010 | NYD | Whiteside | Demoted to reserve roster | | | Before |
| 6/9/2010 | RMO | Encarnacion | Placed on Injured List | | 6/9/2010 | Before |
| 6/9/2010 | RMO | Figgins | Promoted to active roster | | | Before |
| 6/9/2010 | RMO | Kearns | Placed on Injured List | | 6/9/2010 | Before |
| 6/9/2010 | RMO | McDonald,D | Promoted to active roster | | | Before |
| 6/10/2010 | GAR | Mahay | Promoted to active roster | | | Before |
| 6/10/2010 | GAR | Neshek | Demoted to reserve roster | | | Before |
| 6/11/2010 | AST | Belliard | Demoted to reserve roster | | | Before |
| 6/11/2010 | AST | Lind | Activated from Injured List | | | Before |
| 6/11/2010 | BAR | Schierholtz | Demoted to reserve roster | | | Before |
| 6/11/2010 | BAR | Wise | Promoted to active roster | | | Before |
| 6/12/2010 | BAR | Hester | Promoted to active roster | | | Before |
| 6/12/2010 | BAR | Wise | Demoted to reserve roster | | | Before |
| 6/12/2010 | CIO | Scott | Activated from Injured List | | | Before |
| 6/12/2010 | CIO | Wells,C | Demoted to reserve roster | | | Before |
| 6/14/2010 | BAR | Baker,S | Demoted to reserve roster | | | Before |
| 6/14/2010 | BAR | Baker,S | Acquired via trade | CSS | | After |
| 6/14/2010 | BAR | Myers | Traded away | CSS | | After |
| 6/14/2010 | CSS | Axford | Promoted to active roster | | | Before |
| 6/14/2010 | CSS | Lopez,Ja | Promoted to active roster | | | Before |
| 6/14/2010 | CSS | Marte,D | Demoted to reserve roster | | | Before |
| 6/14/2010 | CSS | Myers | Promoted to active roster | | | Before |
| 6/14/2010 | CSS | Romero,JC | Demoted to reserve roster | | | Before |
| 6/14/2010 | CSS | Baker,S | Traded away | BAR | | After |
| 6/14/2010 | CSS | Myers | Acquired via trade | BAR | | After |
| 6/14/2010 | NEP | Carter,VC | Promoted to active roster | | | Before |
| 6/14/2010 | NEP | Thames | Demoted to reserve roster | | | Before |
| 6/15/2010 | BAR | Baker,S | Promoted to active roster | | | Before |
| 6/15/2010 | BAR | Blanco,A | Demoted to reserve roster | | | Before |
| 6/15/2010 | BAR | Feldman | Demoted to reserve roster | | | Before |
| 6/15/2010 | BAR | Guillen,C | Promoted to active roster | | | Before |
| 6/15/2010 | BAR | Hester | Demoted to reserve roster | | | Before |
| 6/15/2010 | BAR | Moore,S | Demoted to reserve roster | | | Before |
| 6/15/2010 | BAR | Schierholtz | Promoted to active roster | | | Before |
| 6/15/2010 | BAR | Wise | Promoted to active roster | | | Before |
| 6/15/2010 | BBG | Betancourt,R | Demoted to reserve roster | | | Before |
| 6/15/2010 | BBG | Humber | Promoted to active roster | | | Before |
| 6/15/2010 | CIO | Raburn | Demoted to reserve roster | | | Before |
| 6/15/2010 | CIO | Sogard | Promoted to active roster | | | Before |
| 6/15/2010 | FDH | Cora | Promoted to active roster | | | Before |
| 6/15/2010 | FDH | Hardy | Demoted to reserve roster | | | Before |
| 6/15/2010 | FDH | Karstens | Promoted to active roster | | | Before |
| 6/15/2010 | FDH | Morton | Demoted to reserve roster | | | Before |
| 6/15/2010 | GAR | Blanton | Promoted to active roster | | | Before |
| 6/15/2010 | GAR | McGee | Demoted to reserve roster | | | Before |
| 6/16/2010 | CIO | Bailey,A | Demoted to reserve roster | | | Before |
| 6/16/2010 | CIO | Doubront | Promoted to active roster | | | Before |
| 6/16/2010 | GAR | Saunders,M | Demoted to reserve roster | | | Before |
| 6/16/2010 | GAR | Wallace | Activated from Injured List | | | Before |
| 6/16/2010 | HAR | Ottavino | Demoted to reserve roster | | | Before |
| 6/16/2010 | SOI | de la Rosa | Activated from Injured List | | | Before |
| 6/16/2010 | SOI | Downs,S | Demoted to reserve roster | | | Before |
| 6/16/2010 | TEW | Escobar,Y | Activated from Injured List | | | Before |
| 6/16/2010 | TEW | Francisco,B | Demoted to reserve roster | | | Before |
| 6/16/2010 | TEW | Guzman | Demoted to reserve roster | | | Before |
| 6/16/2010 | TEW | Mora | Promoted to active roster | | | Before |
| 6/16/2010 | TEW | Paulino,R | Demoted to reserve roster | | | Before |
| 6/16/2010 | TEW | Thole | Promoted to active roster | | | Before |
| 6/17/2010 | AST | Gomez,J | Demoted to reserve roster | | | Before |
| 6/17/2010 | AST | Norris | Activated from Injured List | | | Before |
| 6/17/2010 | CIO | Conger | Promoted to active roster | | | Before |
| 6/17/2010 | CIO | Ross,D | Demoted to reserve roster | | | Before |
| 6/17/2010 | HAR | Boggs,M | Promoted to active roster | | | Before |
| 6/17/2010 | HAR | Murphy,Da | Promoted to active roster | | | Before |
| 6/17/2010 | HAR | Nava | Placed on Injured List | | 6/16/2010 | Before |
| 6/18/2010 | CTW | Kimbrel | Promoted to active roster | | | Before |
| 6/18/2010 | CTW | Lopez,W | Demoted to reserve roster | | | Before |
| 6/18/2010 | CTW | O'Day | Promoted to active roster | | | Before |
| 6/18/2010 | CTW | Soriano,R | Demoted to reserve roster | | | Before |
| 6/18/2010 | FDH | Cora | Promoted to active roster | | | Before |
| 6/18/2010 | FDH | Hardy | Demoted to reserve roster | | | Before |
| 6/18/2010 | FDH | Karstens | Promoted to active roster | | | Before |
| 6/18/2010 | FDH | Morton | Demoted to reserve roster | | | Before |
| 6/18/2010 | GAR | Arrieta | Placed on Injured List | | 6/17/2010 | Before |
| 6/18/2010 | GAR | Volstad | Promoted to active roster | | | Before |
| 6/18/2010 | HAR | Castro,Ja | Demoted to reserve roster | | | Before |
| 6/18/2010 | HAR | Moore,A | Promoted to active roster | | | Before |
| 6/18/2010 | HAR | Murphy,Da | Demoted to reserve roster | | | Before |
| 6/18/2010 | HAR | Navarro,D | Demoted to reserve roster | | | Before |
| 6/18/2010 | HAR | Niese | Promoted to active roster | | | Before |
| 6/18/2010 | HAR | Powell | Promoted to active roster | | | Before |
| 6/19/2010 | CIN | Cordero,F | Demoted to reserve roster | | | Before |
| 6/19/2010 | CIN | Perez,O | Demoted to reserve roster | | | Before |
| 6/19/2010 | CIN | Pettitte | Activated from Injured List | | | Before |
| 6/19/2010 | CIN | Simon | Promoted to active roster | | | Before |
| 6/19/2010 | CIO | Hill,R | Promoted to active roster | | | Before |
| 6/19/2010 | CIO | Mather | Promoted to active roster | | | Before |
| 6/19/2010 | CIO | Morse | Demoted to reserve roster | | | Before |
| 6/19/2010 | CIO | Thornton | Demoted to reserve roster | | | Before |
| 6/19/2010 | NYD | Lewis,J | Promoted to active roster | | | Before |
| 6/19/2010 | NYD | Schlichting | Demoted to reserve roster | | | Before |
| 6/21/2010 | CIO | Edmonds | Activated from Injured List | | | Before |
| 6/21/2010 | CIO | Petersen | Demoted to reserve roster | | | Before |
| 6/21/2010 | CSS | Blanco,G | Demoted to reserve roster | | | Before |
| 6/21/2010 | CSS | Hart | Activated from Injured List | | | Before |
| 6/21/2010 | FDH | Affeldt | Demoted to reserve roster | | | Before |
| 6/21/2010 | FDH | Hawksworth | Promoted to active roster | | | Before |
| 6/22/2010 | BAR | Blevins | Demoted to reserve roster | | | Before |
| 6/22/2010 | BAR | Roenicke | Promoted to active roster | | | Before |
| 6/22/2010 | CBB | Coghlan | Promoted to active roster | | | Before |
| 6/22/2010 | CBB | Ryan,B | Placed on Injured List | | 6/21/2010 | Before |
| 6/22/2010 | CTW | Barton | Promoted to active roster | | | Before |
| 6/22/2010 | CTW | Morales,K | Placed on Injured List | | 6/22/2010 | Before |
| 6/23/2010 | CTW | Medlen | Placed on Injured List | | 6/23/2010 | Before |
| 6/23/2010 | CTW | Stauffer | Promoted to active roster | | | Before |
| 6/24/2010 | RMO | Beckham | Demoted to reserve roster | | | Before |
| 6/24/2010 | RMO | Kearns | Activated from Injured List | | | Before |
| 6/24/2010 | RMO | Nova | Promoted to active roster | | | Before |
| 6/24/2010 | RMO | Tillman | Demoted to reserve roster | | | Before |
| 6/29/2010 | BBG | Aceves | Demoted to reserve roster | | | Before |
| 6/29/2010 | BBG | Luebke | Promoted to active roster | | | Before |
| 6/29/2010 | CEN | Dunn,M | Demoted to reserve roster | | | Before |
| 6/29/2010 | CEN | Floyd | Activated from Injured List | | | Before |
| 6/29/2010 | CEN | Furcal | Activated from Injured List | | | Before |
| 6/29/2010 | CEN | Izturis,M | Demoted to reserve roster | | | Before |
| 6/29/2010 | CIO | Hill,R | Demoted to reserve roster | | | Before |
| 6/29/2010 | CIO | Hudson,D | Promoted to active roster | | | Before |
| 6/29/2010 | CSS | Buehrle | Promoted to active roster | | | Before |
| 6/29/2010 | CSS | Sanchez,J | Demoted to reserve roster | | | Before |
| 6/29/2010 | FDH | Parra,M | Promoted to active roster | | | Before |
| 6/29/2010 | FDH | Romo | Demoted to reserve roster | | | Before |
| 6/30/2010 | ATM | Brignac | Promoted to active roster | | | Before |
| 6/30/2010 | ATM | Roberts,B | Demoted to reserve roster | | | Before |
| 6/30/2010 | BRK | Beltran | Demoted to reserve roster | | | Before |
| 6/30/2010 | BRK | DeJesus | Promoted to active roster | | | Before |
| 6/30/2010 | CSS | Conrad | Demoted to reserve roster | | | Before |
| 6/30/2010 | CSS | Romero,JC | Promoted to active roster | | | Before |
| 6/30/2010 | CSS | Smith,Joe | Demoted to reserve roster | | | Before |
| 6/30/2010 | CSS | Utley | Activated from Injured List | | | Before |
| 6/30/2010 | GAR | Barmes | Placed on Injured List | | 6/30/2010 | Before |
| 6/30/2010 | GAR | Wigginton | Promoted to active roster | | | Before |
| 6/30/2010 | NYD | Farnsworth | Activated from Injured List | | | Before |
| 6/30/2010 | NYD | Thatcher | Demoted to reserve roster | | | Before |
| 7/1/2010 | CIN | Butera | Promoted to active roster | | | Before |
| 7/1/2010 | CIN | Cairo | Demoted to reserve roster | | | Before |
| 7/1/2010 | CIO | Cousins | Demoted to reserve roster | | | Before |
| 7/1/2010 | CIO | Petersen | Promoted to active roster | | | Before |
| 7/1/2010 | FDH | Bailey,H | Promoted to active roster | | | Before |
| 7/1/2010 | FDH | Lohse | Demoted to reserve roster | | | Before |
| 7/1/2010 | TEW | Bard,D | Demoted to reserve roster | | | Before |
| 7/1/2010 | TEW | Callaspo | Demoted to reserve roster | | | Before |
| 7/1/2010 | TEW | Francisco,B | Promoted to active roster | | | Before |
| 7/1/2010 | TEW | Fukudome | Promoted to active roster | | | Before |
| 7/1/2010 | TEW | Hensley | Promoted to active roster | | | Before |
| 7/1/2010 | TEW | Jay | Demoted to reserve roster | | | Before |
| 7/2/2010 | BBG | Hanigan | Demoted to reserve roster | | | Before |
| 7/2/2010 | BBG | Olivo | Promoted to active roster | | | Before |
| 7/3/2010 | ATM | Brignac | Demoted to reserve roster | | | Before |
| 7/3/2010 | ATM | Morneau | Promoted to active roster | | | Before |
| 7/3/2010 | ATM | Motte | Demoted to reserve roster | | | Before |
| 7/3/2010 | ATM | Street | Promoted to active roster | | | Before |
| 7/3/2010 | BAR | Qualls | Demoted to reserve roster | | | Before |
| 7/3/2010 | BAR | Valdes | Promoted to active roster | | | Before |
| 7/3/2010 | CIN | Frieri | Demoted to reserve roster | | | Before |
| 7/3/2010 | CIN | LeCure | Promoted to active roster | | | Before |
| 7/4/2010 | HAR | Davis,D | Promoted to active roster | | | Before |
| 7/4/2010 | HAR | Niese | Placed on Injured List | | 7/2/2010 | Before |
| 7/6/2010 | BRK | Danks | Placed on Injured List | | 7/6/2010 | Before |
| 7/6/2010 | BRK | Rogers,M | Promoted to active roster | | | Before |
| 7/6/2010 | CEN | Casilla,A | Activated from Injured List | | | Before |
| 7/6/2010 | CEN | Casilla,A | Demoted to reserve roster | | | Before |
| 7/6/2010 | CEN | Dunn,M | Promoted to active roster | | | Before |
| 7/6/2010 | CEN | Maldonado | Promoted to active roster | | | Before |
| 7/6/2010 | CEN | Casilla,A | Acquired via trade | CIO | | After |
| 7/6/2010 | CEN | Dickey | Acquired via trade | CIO | | After |
| 7/6/2010 | CEN | Hammel | Acquired via trade | CTW | | After |
| 7/6/2010 | CEN | Hudson,T | Acquired via trade | CIO | | After |
| 7/6/2010 | CEN | Jimenez | Traded away | CTW | | After |
| 7/6/2010 | CEN | Marmol | Traded away | CTW | | After |
| 7/6/2010 | CEN | Medlen | Acquired via trade | CTW | | After |
| 7/6/2010 | CEN | Oswalt | Traded away | CIO | | After |
| 7/6/2010 | CEN | Santana,J | Traded away | CIO | | After |
| 7/6/2010 | CEN | Valencia | Traded away | CIO | | After |
| 7/6/2010 | CIO | Morel | Demoted to reserve roster | | | Before |
| 7/6/2010 | CIO | Morse | Promoted to active roster | | | Before |
| 7/6/2010 | CIO | Petersen | Demoted to reserve roster | | | Before |
| 7/6/2010 | CIO | Casilla,A | Traded away | CEN | | After |
| 7/6/2010 | CIO | Dickey | Traded away | CEN | | After |
| 7/6/2010 | CIO | Hudson,T | Traded away | CEN | | After |
| 7/6/2010 | CIO | Oswalt | Acquired via trade | CEN | | After |
| 7/6/2010 | CIO | Santana,J | Acquired via trade | CEN | | After |
| 7/6/2010 | CIO | Valencia | Acquired via trade | CEN | | After |
| 7/6/2010 | CTW | Masset | Demoted to reserve roster | | | Before |
| 7/6/2010 | CTW | Hammel | Traded away | CEN | | After |
| 7/6/2010 | CTW | Jimenez | Acquired via trade | CEN | | After |
| 7/6/2010 | CTW | Marmol | Acquired via trade | CEN | | After |
| 7/6/2010 | CTW | Medlen | Traded away | CEN | | After |
| 7/7/2010 | CIN | Cordero,F | Promoted to active roster | | | Before |
| 7/7/2010 | CIN | Pena,B | Demoted to reserve roster | | | Before |
| 7/7/2010 | CSS | Axford | Demoted to reserve roster | | | Before |
| 7/7/2010 | CSS | Marte,D | Promoted to active roster | | | Before |
| 7/7/2010 | CSS | Moylan | Promoted to active roster | | | Before |
| 7/7/2010 | CSS | Venters | Demoted to reserve roster | | | Before |
| 7/7/2010 | FDH | Bailey,H | Placed on Injured List | | 7/6/2010 | Before |
| 7/7/2010 | FDH | Blackburn | Promoted to active roster | | | Before |
| 7/7/2010 | RMO | Nova | Demoted to reserve roster | | | Before |
| 7/7/2010 | RMO | Slowey | Promoted to active roster | | | Before |
| 7/7/2010 | SOI | Andino | Demoted to reserve roster | | | Before |
| 7/7/2010 | SOI | Bastardo | Promoted to active roster | | | Before |
| 7/7/2010 | SOI | Francis | Promoted to active roster | | | Before |
| 7/7/2010 | SOI | MacDougal | Promoted to active roster | | | Before |
| 7/7/2010 | SOI | Paulino,F | Demoted to reserve roster | | | Before |
| 7/7/2010 | SOI | Valverde | Demoted to reserve roster | | | Before |
| 7/8/2010 | BAR | Kelley | Demoted to reserve roster | | | Before |
| 7/8/2010 | BAR | Veras | Promoted to active roster | | | Before |
| 7/8/2010 | CEN | Casilla,A | Promoted to active roster | | | Before |
| 7/8/2010 | CEN | Dunn,M | Demoted to reserve roster | | | Before |
| 7/8/2010 | CEN | Maldonado | Demoted to reserve roster | | | Before |
| 7/8/2010 | CEN | Medlen | Activated from Injured List | | | Before |
| 7/8/2010 | CIO | Burriss | Promoted to active roster | | | Before |
| 7/8/2010 | CIO | Conger | Demoted to reserve roster | | | Before |
| 7/8/2010 | CIO | Doubront | Demoted to reserve roster | | | Before |
| 7/8/2010 | CIO | Mather | Demoted to reserve roster | | | Before |
| 7/8/2010 | CIO | Padilla | Promoted to active roster | | | Before |
| 7/8/2010 | CIO | Raburn | Promoted to active roster | | | Before |
| 7/8/2010 | CIO | Ross,D | Promoted to active roster | | | Before |
| 7/8/2010 | CIO | Sogard | Placed on Injured List | | 7/6/2010 | Before |
| 7/8/2010 | CTW | Lopez,W | Promoted to active roster | | | Before |
| 7/8/2010 | CTW | Stauffer | Placed on Injured List | | 7/8/2010 | Before |
| 7/8/2010 | NEP | Freese | Placed on Injured List | | 7/8/2010 | Before |
| 7/9/2010 | BAR | Choate | Promoted to active roster | | | Before |
| 7/9/2010 | BAR | Dotel | Demoted to reserve roster | | | Before |
| 7/9/2010 | NEP | Murphy,Do | Promoted to active roster | | | Before |
| 7/9/2010 | NYD | Broxton | Promoted to active roster | | | Before |
| 7/9/2010 | NYD | Ekstrom | Demoted to reserve roster | | | Before |
| 7/10/2010 | CBB | Carroll,J | Placed on Injured List | | 7/2/2010 | Before |
| 7/10/2010 | CBB | Misch | Promoted to active roster | | | Before |
| 7/10/2010 | CBB | Ryan,B | Activated from Injured List | | | Before |
| 7/10/2010 | CBB | Tabata | Demoted to reserve roster | | | Before |
| 7/10/2010 | CBB | Tabata | Promoted to active roster | | | Before |
| 7/10/2010 | CBB | Walker,T | Demoted to reserve roster | | | Before |
| 7/10/2010 | GAR | Ankiel | Demoted to reserve roster | | | Before |
| 7/10/2010 | GAR | Harris,W | Promoted to active roster | | | Before |
| 7/10/2010 | GAR | Kouzmanoff | Placed on Injured List | | 7/10/2010 | Before |
| 7/10/2010 | GAR | Ludwick | Promoted to active roster | | | Before |
| 7/10/2010 | NYD | Billingsley | Placed on Injured List | | 7/9/2010 | Before |
| 7/10/2010 | NYD | Mitre | Promoted to active roster | | | Before |
| 7/11/2010 | CIN | Alvarez | Demoted to reserve roster | | | Before |
| 7/11/2010 | CIN | Cairo | Promoted to active roster | | | Before |
| 7/11/2010 | FDH | Beachy | Demoted to reserve roster | | | Before |
| 7/11/2010 | FDH | Morton | Promoted to active roster | | | Before |
| 7/11/2010 | NEP | Cook | Promoted to active roster | | | Before |
| 7/11/2010 | NEP | Peavy | Demoted to reserve roster | | | Before |
| 7/12/2010 | AST | Crowe | Promoted to active roster | | | Before |
| 7/12/2010 | AST | Davies | Demoted to reserve roster | | | Before |
| 7/12/2010 | AST | Figueroa | Promoted to active roster | | | Before |
| 7/12/2010 | AST | McLouth | Demoted to reserve roster | | | Before |
| 7/12/2010 | AST | Crowe | Acquired via trade | CSS | | After |
| 7/12/2010 | AST | Figueroa | Acquired via trade | CSS | | After |
| 7/12/2010 | AST | Fuentes | Traded away | CSS | | After |
| 7/12/2010 | AST | Punto | Traded away | CSS | | After |
| 7/12/2010 | CEN | Bard,J | Placed on Injured List | | 7/12/2010 | Before |
| 7/12/2010 | CEN | Maldonado | Promoted to active roster | | | Before |
| 7/12/2010 | CSS | Fuentes | Promoted to active roster | | | Before |
| 7/12/2010 | CSS | Marte,D | Demoted to reserve roster | | | Before |
| 7/12/2010 | CSS | Punto | Demoted to reserve roster | | | Before |
| 7/12/2010 | CSS | Romero,JC | Demoted to reserve roster | | | Before |
| 7/12/2010 | CSS | Venters | Promoted to active roster | | | Before |
| 7/12/2010 | CSS | Crowe | Traded away | AST | | After |
| 7/12/2010 | CSS | Figueroa | Traded away | AST | | After |
| 7/12/2010 | CSS | Fuentes | Acquired via trade | AST | | After |
| 7/12/2010 | CSS | Punto | Acquired via trade | AST | | After |
| 7/12/2010 | HAR | Carp | Demoted to reserve roster | | | Before |
| 7/12/2010 | NEP | Francisco,F | Promoted to active roster | | | Before |
| 7/12/2010 | NEP | Wheeler | Demoted to reserve roster | | | Before |
| 7/13/2010 | BRK | Berkman | Demoted to reserve roster | | | Before |
| 7/13/2010 | BRK | Izturis,C | Promoted to active roster | | | Before |
| 7/13/2010 | CIO | Acosta | Demoted to reserve roster | | | Before |
| 7/13/2010 | CIO | Doubront | Promoted to active roster | | | Before |
| 7/13/2010 | FDH | Affeldt | Promoted to active roster | | | Before |
| 7/13/2010 | FDH | Tomlin | Demoted to reserve roster | | | Before |
| 7/13/2010 | GAR | Arrieta | Activated from Injured List | | | Before |
| 7/13/2010 | RMO | Stanton | Demoted to reserve roster | | | Before |
| 7/15/2010 | AST | Gonzalez,Alb | Promoted to active roster | | | Before |
| 7/15/2010 | AST | LaRoche,An | Promoted to active roster | | | Before |
| 7/15/2010 | AST | Lugo | Demoted to reserve roster | | | Before |
| 7/15/2010 | CIO | Bailey,A | Promoted to active roster | | | Before |
| 7/15/2010 | CIO | Buck,J | Promoted to active roster | | | Before |
| 7/15/2010 | CIO | Burriss | Demoted to reserve roster | | | Before |
| 7/15/2010 | CIO | Doubront | Demoted to reserve roster | | | Before |
| 7/15/2010 | CIO | Duncan | Promoted to active roster | | | Before |
| 7/15/2010 | CIO | Padilla | Demoted to reserve roster | | | Before |
| 7/15/2010 | CIO | Ross,D | Demoted to reserve roster | | | Before |
| 7/15/2010 | CIO | Thornton | Promoted to active roster | | | Before |
| 7/16/2010 | FDH | Cervelli | Placed on Injured List | | 7/16/2010 | Before |
| 7/16/2010 | FDH | Cruz,L | Promoted to active roster | | | Before |
| 7/16/2010 | NYD | Counsell | Promoted to active roster | | | Before |
| 7/16/2010 | NYD | Rolen | Placed on Injured List | | 7/16/2010 | Before |
| 7/16/2010 | NYD | Whiteside | Promoted to active roster | | | Before |
| 7/16/2010 | NYD | Zaun | Demoted to reserve roster | | | Before |
| 7/17/2010 | BAR | Pedroia | Placed on Injured List | | 7/17/2010 | Before |
| 7/17/2010 | BAR | Torres,C | Promoted to active roster | | | Before |
| 7/17/2010 | BBG | Hanigan | Promoted to active roster | | | Before |
| 7/17/2010 | BBG | Montero | Demoted to reserve roster | | | Before |
| 7/17/2010 | CBB | Cabrera,E | Demoted to reserve roster | | | Before |
| 7/17/2010 | CBB | Carroll,J | Activated from Injured List | | | Before |
| 7/17/2010 | CBB | Hill,K | Promoted to active roster | | | Before |
| 7/17/2010 | CBB | Walker,N | Demoted to reserve roster | | | Before |
| 7/17/2010 | CEN | Dunn,M | Promoted to active roster | | | Before |
| 7/17/2010 | CEN | Guerrier | Demoted to reserve roster | | | Before |
| 7/17/2010 | CEN | Howard | Demoted to reserve roster | | | Before |
| 7/17/2010 | CEN | Izturis,M | Promoted to active roster | | | Before |
| 7/17/2010 | CEN | Jones,C | Demoted to reserve roster | | | Before |
| 7/17/2010 | CEN | Lowe,M | Promoted to active roster | | | Before |
| 7/17/2010 | CEN | Morrison | Demoted to reserve roster | | | Before |
| 7/17/2010 | CEN | Revere | Promoted to active roster | | | Before |
| 7/17/2010 | CEN | Roberts,R | Promoted to active roster | | | Before |
| 7/17/2010 | CEN | Santos | Demoted to reserve roster | | | Before |
| 7/17/2010 | CEN | Soria | Demoted to reserve roster | | | Before |
| 7/17/2010 | CEN | Wright,W | Promoted to active roster | | | Before |
| 7/17/2010 | HAR | Nava | Activated from Injured List | | | Before |
| 7/17/2010 | RMO | Beckham | Promoted to active roster | | | Before |
| 7/17/2010 | RMO | Capuano | Demoted to reserve roster | | | Before |
| 7/17/2010 | RMO | Duke | Promoted to active roster | | | Before |
| 7/17/2010 | RMO | Kinsler | Demoted to reserve roster | | | Before |
| 7/17/2010 | RMO | Martin,R | Demoted to reserve roster | | | Before |
| 7/17/2010 | RMO | Moeller | Promoted to active roster | | | Before |
| 7/17/2010 | RMO | Molina,G | Promoted to active roster | | | Before |
| 7/17/2010 | RMO | Monasterios | Demoted to reserve roster | | | Before |
| 7/17/2010 | RMO | Ohlendorf | Promoted to active roster | | | Before |
| 7/17/2010 | TEW | Adams | Demoted to reserve roster | | | Before |
| 7/17/2010 | TEW | Johnson,Ji | Promoted to active roster | | | Before |
| 7/18/2010 | BRK | Rogers,M | Demoted to reserve roster | | | Before |
| 7/18/2010 | CEN | Dunn,M | Demoted to reserve roster | | | Before |
| 7/18/2010 | CEN | Infante,G | Promoted to active roster | | | Before |
| 7/18/2010 | DLM | Barney | Demoted to reserve roster | | | Before |
| 7/18/2010 | DLM | Frasor | Demoted to reserve roster | | | Before |
| 7/18/2010 | DLM | O'Flaherty | Activated from Injured List | | | Before |
| 7/18/2010 | DLM | Podsednik | Activated from Injured List | | | Before |
| 7/18/2010 | DLM | Smith,S | Demoted to reserve roster | | | Before |
| 7/18/2010 | DLM | Vizquel | Promoted to active roster | | | Before |
| 7/18/2010 | FDH | Lohse | Promoted to active roster | | | Before |
| 7/18/2010 | FDH | Parnell | Demoted to reserve roster | | | Before |
| 7/18/2010 | NYD | Martinez,O | Demoted to reserve roster | | | Before |
| 7/18/2010 | NYD | Purcey | Promoted to active roster | | | Before |
| 7/19/2010 | AST | Bush | Placed on Injured List | | 7/19/2010 | Before |
| 7/19/2010 | AST | Huff,D | Demoted to reserve roster | | | Before |
| 7/19/2010 | AST | McCutchen,D | Promoted to active roster | | | Before |
| 7/19/2010 | AST | Richard | Promoted to active roster | | | Before |
| 7/19/2010 | ATM | Alfonzo | Acquired via trade | CIO | | After |
| 7/19/2010 | ATM | Fielder | Acquired via trade | CIO | | After |
| 7/19/2010 | ATM | May | Acquired via trade | CIO | | After |
| 7/19/2010 | ATM | Morneau | Traded away | CIO | | After |
| 7/19/2010 | ATM | Roberts,B | Traded away | CIO | | After |
| 7/19/2010 | ATM | Wilson,Br | Traded away | CIO | | After |
| 7/19/2010 | BRK | Zumaya | Promoted to active roster | | | Before |
| 7/19/2010 | CIN | Garcia,F | Promoted to active roster | | | Before |
| 7/19/2010 | CIN | LeCure | Demoted to reserve roster | | | Before |
| 7/19/2010 | CIO | Alfonzo | Traded away | ATM | | After |
| 7/19/2010 | CIO | Fielder | Traded away | ATM | | After |
| 7/19/2010 | CIO | May | Traded away | ATM | | After |
| 7/19/2010 | CIO | Morneau | Acquired via trade | ATM | | After |
| 7/19/2010 | CIO | Roberts,B | Acquired via trade | ATM | | After |
| 7/19/2010 | CIO | Wilson,Br | Acquired via trade | ATM | | After |
| 7/19/2010 | CSS | Axford | Promoted to active roster | | | Before |
| 7/19/2010 | CSS | Blanco,G | Promoted to active roster | | | Before |
| 7/19/2010 | CSS | Marte,D | Demoted to reserve roster | | | Before |
| 7/19/2010 | CSS | Marte,D | Promoted to active roster | | | Before |
| 7/19/2010 | CSS | McDonald,Jo | Demoted to reserve roster | | | Before |
| 7/19/2010 | CSS | Moylan | Demoted to reserve roster | | | Before |
| 7/19/2010 | CSS | Romero,JC | Promoted to active roster | | | Before |
| 7/19/2010 | CSS | Smith,Joe | Promoted to active roster | | | Before |
| 7/19/2010 | CSS | Venters | Demoted to reserve roster | | | Before |
| 7/19/2010 | CSS | Victorino | Demoted to reserve roster | | | Before |
| 7/19/2010 | CSS | Webb | Demoted to reserve roster | | | Before |
| 7/19/2010 | CTW | Albers | Promoted to active roster | | | Before |
| 7/19/2010 | CTW | Carmona | Promoted to active roster | | | Before |
| 7/19/2010 | CTW | Chacin,J | Demoted to reserve roster | | | Before |
| 7/19/2010 | CTW | Lopez,W | Demoted to reserve roster | | | Before |
| 7/19/2010 | CTW | O'Day | Demoted to reserve roster | | | Before |
| 7/19/2010 | CTW | Soriano,R | Promoted to active roster | | | Before |
| 7/19/2010 | HAR | Casilla,S | Demoted to reserve roster | | | Before |
| 7/19/2010 | HAR | French | Promoted to active roster | | | Before |
| 7/19/2010 | HAR | Marquis | Promoted to active roster | | | Before |
| 7/19/2010 | HAR | Wood,Tr | Demoted to reserve roster | | | Before |
| 7/19/2010 | SOI | Avila | Demoted to reserve roster | | | Before |
| 7/19/2010 | SOI | Beckett | Demoted to reserve roster | | | Before |
| 7/19/2010 | SOI | Varitek | Promoted to active roster | | | Before |
| 7/19/2010 | SOI | Young,CR | Promoted to active roster | | | Before |
| 7/20/2010 | BBG | Burnett,S | Promoted to active roster | | | Before |
| 7/20/2010 | BBG | Harrison | Promoted to active roster | | | Before |
| 7/20/2010 | BBG | Humber | Demoted to reserve roster | | | Before |
| 7/20/2010 | BBG | Marshall | Demoted to reserve roster | | | Before |
| 7/20/2010 | CIO | Loe | Demoted to reserve roster | | | Before |
| 7/21/2010 | BRK | Danks | Activated from Injured List | | | Before |
| 7/21/2010 | BRK | Feliz,N | Demoted to reserve roster | | | Before |
| 7/21/2010 | CIN | LaRue | Promoted to active roster | | | Before |
| 7/21/2010 | CIN | Willingham | Demoted to reserve roster | | | Before |
| 7/21/2010 | CTW | Cust | Promoted to active roster | | | Before |
| 7/21/2010 | CTW | Joyce | Demoted to reserve roster | | | Before |
| 7/21/2010 | GAR | Hoffman | Demoted to reserve roster | | | Before |
| 7/21/2010 | GAR | LeBlanc | Demoted to reserve roster | | | Before |
| 7/21/2010 | GAR | Willis | Promoted to active roster | | | Before |
| 7/22/2010 | BAR | Hawkins | Promoted to active roster | | | Before |
| 7/22/2010 | BAR | Storen | Demoted to reserve roster | | | Before |
| 7/22/2010 | CIN | Kendrick,K | Promoted to active roster | | | Before |
| 7/22/2010 | CIN | Simon | Demoted to reserve roster | | | Before |
| 7/22/2010 | NEP | Hunter,Tom | Promoted to active roster | | | Before |
| 7/22/2010 | NEP | Morrow | Demoted to reserve roster | | | Before |
| 7/23/2010 | ATM | Nolasco | Promoted to active roster | | | Before |
| 7/23/2010 | CIN | Logan | Demoted to reserve roster | | | Before |
| 7/23/2010 | CIN | Perez,O | Promoted to active roster | | | Before |
| 7/23/2010 | CSS | Keppinger | Promoted to active roster | | | Before |
| 7/23/2010 | CSS | Moylan | Promoted to active roster | | | Before |
| 7/23/2010 | CSS | Price | Placed on Injured List | | 7/22/2010 | Before |
| 7/23/2010 | CSS | Punto | Promoted to active roster | | | Before |
| 7/23/2010 | CSS | Putz | Demoted to reserve roster | | | Before |
| 7/23/2010 | CSS | Sanchez,J | Promoted to active roster | | | Before |
| 7/23/2010 | CSS | Santiago | Placed on Injured List | | 7/23/2010 | Before |
| 7/23/2010 | HAR | Davis,D | Demoted to reserve roster | | | Before |
| 7/23/2010 | HAR | Niese | Activated from Injured List | | | Before |
| 7/23/2010 | RMO | Encarnacion | Activated from Injured List | | | Before |
| 7/23/2010 | RMO | Helton | Demoted to reserve roster | | | Before |
| 7/26/2010 | BAR | Fien | Promoted to active roster | | | Before |
| 7/26/2010 | BAR | Roenicke | Demoted to reserve roster | | | Before |
| 7/26/2010 | BAR | Dunn,M | Acquired via trade | CEN | | After |
| 7/26/2010 | BAR | Ibanez | Acquired via trade | CEN | | After |
| 7/26/2010 | BAR | Qualls | Traded away | CEN | | After |
| 7/26/2010 | BAR | Silva | Traded away | CEN | | After |
| 7/26/2010 | CEN | Carlin | Promoted to active roster | | | Before |
| 7/26/2010 | CEN | Infante,G | Demoted to reserve roster | | | Before |
| 7/26/2010 | CEN | Dunn,M | Traded away | BAR | | After |
| 7/26/2010 | CEN | Ibanez | Traded away | BAR | | After |
| 7/26/2010 | CEN | Qualls | Acquired via trade | BAR | | After |
| 7/26/2010 | CEN | Silva | Acquired via trade | BAR | | After |
| 7/26/2010 | CIN | Bernadina | Promoted to active roster | | | Before |
| 7/26/2010 | CIN | Kottaras | Demoted to reserve roster | | | Before |
| 7/26/2010 | NYD | Billingsley | Activated from Injured List | | | Before |
| 7/26/2010 | NYD | Purcey | Demoted to reserve roster | | | Before |
| 7/27/2010 | BAR | Hawkins | Demoted to reserve roster | | | Before |
| 7/27/2010 | BAR | Hester | Promoted to active roster | | | Before |
| 7/27/2010 | CEN | Bard,J | Activated from Injured List | | | Before |
| 7/27/2010 | CEN | Bray | Promoted to active roster | | | Before |
| 7/27/2010 | CEN | Carlin | Demoted to reserve roster | | | Before |
| 7/27/2010 | CEN | Lowe,M | Demoted to reserve roster | | | Before |
| 7/27/2010 | CEN | Silva | Promoted to active roster | | | Before |
| 7/27/2010 | CEN | Wright,W | Demoted to reserve roster | | | Before |
| 7/27/2010 | CIO | Buck,J | Demoted to reserve roster | | | Before |
| 7/27/2010 | CIO | McClendon | Promoted to active roster | | | Before |
| 7/27/2010 | CIO | Morel | Promoted to active roster | | | Before |
| 7/27/2010 | CIO | Rodriguez,A | Demoted to reserve roster | | | Before |
| 7/27/2010 | CIO | Ross,D | Promoted to active roster | | | Before |
| 7/27/2010 | CIO | Thornton | Demoted to reserve roster | | | Before |
| 7/27/2010 | FDH | Cash | Placed on Injured List | | 7/27/2010 | Before |
| 7/27/2010 | FDH | Ellis,AJ | Promoted to active roster | | | Before |
| 7/28/2010 | BAR | Shoppach | Placed on Injured List | | 7/28/2010 | Before |
| 7/28/2010 | SOI | Granderson | Demoted to reserve roster | | | Before |
| 7/28/2010 | SOI | Hayes | Promoted to active roster | | | Before |
| 7/29/2010 | AST | Davies | Promoted to active roster | | | Before |
| 7/29/2010 | AST | Fister | Demoted to reserve roster | | | Before |
| 7/29/2010 | AST | Wright,J | Traded away | CEN | | After |
| 7/29/2010 | AST | Wright,W | Acquired via trade | CEN | | After |
| 7/29/2010 | BRK | Berkman | Promoted to active roster | | | Before |
| 7/29/2010 | BRK | Hernandez,Lu | Demoted to reserve roster | | | Before |
| 7/29/2010 | CEN | Maldonado | Demoted to reserve roster | | | Before |
| 7/29/2010 | CEN | Wright,J | Promoted to active roster | | | Before |
| 7/29/2010 | CEN | Duensing | Acquired via trade | DLM | | After |
| 7/29/2010 | CEN | Lowe,M | Traded away | DLM | | After |
| 7/29/2010 | CEN | Qualls | Traded away | DLM | | After |
| 7/29/2010 | CEN | Wright,J | Acquired via trade | AST | | After |
| 7/29/2010 | CEN | Wright,W | Traded away | AST | | After |
| 7/29/2010 | CIO | Drew,JD | Demoted to reserve roster | | | Before |
| 7/29/2010 | CIO | Mather | Promoted to active roster | | | Before |
| 7/29/2010 | CIO | Bard,D | Acquired via trade | TEW | | After |
| 7/29/2010 | CIO | Barton | Acquired via trade | CTW | | After |
| 7/29/2010 | CIO | Belisle | Traded away | TEW | | After |
| 7/29/2010 | CIO | Buck,J | Traded away | CTW | | After |
| 7/29/2010 | CIO | Germano | Acquired via trade | TEW | | After |
| 7/29/2010 | CIO | Morneau | Traded away | CTW | | After |
| 7/29/2010 | CIO | Rodriguez,A | Traded away | TEW | | After |
| 7/29/2010 | CSS | Axford | Demoted to reserve roster | | | Before |
| 7/29/2010 | CSS | Braun | Demoted to reserve roster | | | Before |
| 7/29/2010 | CSS | Lopez,Ja | Demoted to reserve roster | | | Before |
| 7/29/2010 | CSS | Putz | Promoted to active roster | | | Before |
| 7/29/2010 | CSS | Venters | Promoted to active roster | | | Before |
| 7/29/2010 | CSS | Victorino | Promoted to active roster | | | Before |
| 7/29/2010 | CTW | Kuo | Demoted to reserve roster | | | Before |
| 7/29/2010 | CTW | Lopez,W | Promoted to active roster | | | Before |
| 7/29/2010 | CTW | Soriano,R | Demoted to reserve roster | | | Before |
| 7/29/2010 | CTW | Stauffer | Activated from Injured List | | | Before |
| 7/29/2010 | CTW | Barton | Traded away | CIO | | After |
| 7/29/2010 | CTW | Buck,J | Acquired via trade | CIO | | After |
| 7/29/2010 | CTW | Morneau | Acquired via trade | CIO | | After |
| 7/29/2010 | DLM | Duensing | Traded away | CEN | | After |
| 7/29/2010 | DLM | Lowe,M | Acquired via trade | CEN | | After |
| 7/29/2010 | DLM | Qualls | Acquired via trade | CEN | | After |
| 7/29/2010 | NYD | Jenks | Placed on Injured List | | 7/29/2010 | Before |
| 7/29/2010 | NYD | Kohn | Promoted to active roster | | | Before |
| 7/29/2010 | NYD | Purcey | Promoted to active roster | | | Before |
| 7/29/2010 | NYD | Rhodes | Demoted to reserve roster | | | Before |
| 7/29/2010 | TEW | Bard,D | Traded away | CIO | | After |
| 7/29/2010 | TEW | Belisle | Acquired via trade | CIO | | After |
| 7/29/2010 | TEW | Germano | Traded away | CIO | | After |
| 7/29/2010 | TEW | Rodriguez,A | Acquired via trade | CIO | | After |
| 7/31/2010 | ATM | Holland,G | Promoted to active roster | | | Before |
| 7/31/2010 | ATM | League | Demoted to reserve roster | | | Before |
| 7/31/2010 | ATM | Nunez,L | Promoted to active roster | | | Before |
| 7/31/2010 | ATM | Street | Demoted to reserve roster | | | Before |
| 7/31/2010 | BAR | Ibanez | Promoted to active roster | | | Before |
| 7/31/2010 | BBG | Cameron | Traded away | GAR | | After |
| 7/31/2010 | BBG | Gload | Acquired via trade | GAR | | After |
| 7/31/2010 | BRK | Morales,J | Traded away | NYD | | After |
| 7/31/2010 | CEN | Bray | Demoted to reserve roster | | | Before |
| 7/31/2010 | CEN | Duensing | Promoted to active roster | | | Before |
| 7/31/2010 | CIO | Duncan | Demoted to reserve roster | | | Before |
| 7/31/2010 | CIO | Germano | Promoted to active roster | | | Before |
| 7/31/2010 | CIO | Sogard | Activated from Injured List | | | Before |
| 7/31/2010 | CTW | Buck,J | Promoted to active roster | | | Before |
| 7/31/2010 | CTW | Santana,C | Demoted to reserve roster | | | Before |
| 7/31/2010 | GAR | Barmes | Activated from Injured List | | | Before |
| 7/31/2010 | GAR | Castro,S | Placed on Injured List | | 7/26/2010 | Before |
| 7/31/2010 | GAR | Cameron | Acquired via trade | BBG | | After |
| 7/31/2010 | GAR | Gload | Traded away | BBG | | After |
| 7/31/2010 | NYD | Morales,J | Acquired via trade | BRK | | After |
| 7/31/2010 | TEW | Belisle | Demoted to reserve roster | | | Before |
| 7/31/2010 | TEW | Mora | Demoted to reserve roster | | | Before |
| 7/31/2010 | TEW | Rodriguez,A | Promoted to active roster | | | Before |
| 8/1/2010 | AST | Wright,W | Promoted to active roster | | | Before |
| 8/1/2010 | AST | Ziegler | Demoted to reserve roster | | | Before |
| 8/1/2010 | BBG | Gload | Demoted to reserve roster | | | Before |
| 8/1/2010 | CIN | Miller,A | Promoted to active roster | | | Before |
| 8/1/2010 | CIN | Perez,O | Demoted to reserve roster | | | Before |
| 8/1/2010 | GAR | Cameron | Promoted to active roster | | | Before |
| 8/1/2010 | NYD | Fontenot | Demoted to reserve roster | | | Before |
| 8/1/2010 | NYD | Rolen | Activated from Injured List | | | Before |
| 8/2/2010 | NEP | Belisario | Demoted to reserve roster | | | Before |
| 8/2/2010 | NEP | Carter,VC | Demoted to reserve roster | | | Before |
| 8/2/2010 | NEP | Freese | Activated from Injured List | | | Before |
| 8/2/2010 | NEP | Thayer | Promoted to active roster | | | Before |
| 8/2/2010 | RMO | Davis,B | Demoted to reserve roster | | | Before |
| 8/2/2010 | RMO | Quiroz | Promoted to active roster | | | Before |
| 8/3/2010 | AST | Bush | Activated from Injured List | | | Before |
| 8/3/2010 | AST | Richard | Demoted to reserve roster | | | Before |
| 8/3/2010 | BAR | Fien | Demoted to reserve roster | | | Before |
| 8/3/2010 | BAR | Morales,F | Promoted to active roster | | | Before |
| 8/3/2010 | BBG | Betemit | Demoted to reserve roster | | | Before |
| 8/3/2010 | BBG | Thome | Promoted to active roster | | | Before |
| 8/3/2010 | FDH | Cervelli | Activated from Injured List | | | Before |
| 8/3/2010 | FDH | Ellis,AJ | Demoted to reserve roster | | | Before |
| 8/3/2010 | RMO | Figgins | Demoted to reserve roster | | | Before |
| 8/3/2010 | RMO | Kinsler | Promoted to active roster | | | Before |
| 8/4/2010 | CEN | Guerrier | Promoted to active roster | | | Before |
| 8/4/2010 | CEN | Renteria | Demoted to reserve roster | | | Before |
| 8/4/2010 | CTW | Hall | Demoted to reserve roster | | | Before |
| 8/4/2010 | CTW | Morales,K | Activated from Injured List | | | Before |
| 8/5/2010 | CIO | Bard,D | Promoted to active roster | | | Before |
| 8/5/2010 | CIO | Santana,J | Demoted to reserve roster | | | Before |
| 8/5/2010 | GAR | Cruz,J | Promoted to active roster | | | Before |
| 8/5/2010 | GAR | Kouzmanoff | Activated from Injured List | | | Before |
| 8/5/2010 | GAR | Pena,T | Promoted to active roster | | | Before |
| 8/5/2010 | GAR | Rodney | Demoted to reserve roster | | | Before |
| 8/5/2010 | GAR | Wakefield | Demoted to reserve roster | | | Before |
| 8/5/2010 | NEP | Murphy,Do | Demoted to reserve roster | | | Before |
| 8/5/2010 | NEP | Ransom | Promoted to active roster | | | Before |
| 8/5/2010 | RMO | Martin,R | Promoted to active roster | | | Before |
| 8/5/2010 | RMO | Molina,G | Demoted to reserve roster | | | Before |
| 8/6/2010 | BAR | Feldman | Promoted to active roster | | | Before |
| 8/6/2010 | BAR | Hughes,P | Demoted to reserve roster | | | Before |
| 8/6/2010 | BAR | Mazzaro | Demoted to reserve roster | | | Before |
| 8/6/2010 | BAR | Volquez | Promoted to active roster | | | Before |
| 8/6/2010 | BBG | Betemit | Promoted to active roster | | | Before |
| 8/6/2010 | BBG | Downs,M | Demoted to reserve roster | | | Before |
| 8/6/2010 | BBG | Montero | Promoted to active roster | | | Before |
| 8/6/2010 | CSS | Axford | Promoted to active roster | | | Before |
| 8/6/2010 | CSS | Brantley | Promoted to active roster | | | Before |
| 8/6/2010 | CSS | Cain,L | Demoted to reserve roster | | | Before |
| 8/6/2010 | CSS | Lopez,Ja | Promoted to active roster | | | Before |
| 8/6/2010 | CSS | Marcum | Placed on Injured List | | 8/5/2010 | Before |
| 8/6/2010 | CSS | Price | Activated from Injured List | | | Before |
| 8/6/2010 | CSS | Putz | Demoted to reserve roster | | | Before |
| 8/6/2010 | CSS | Smith,Joe | Demoted to reserve roster | | | Before |
| 8/6/2010 | FDH | Carrasco,C | Promoted to active roster | | | Before |
| 8/6/2010 | FDH | Cecil | Promoted to active roster | | | Before |
| 8/6/2010 | FDH | Cervelli | Activated from Injured List | | | Before |
| 8/6/2010 | FDH | Ellis,AJ | Demoted to reserve roster | | | Before |
| 8/6/2010 | FDH | Jepsen | Demoted to reserve roster | | | Before |
| 8/6/2010 | FDH | Morton | Demoted to reserve roster | | | Before |
| 8/6/2010 | NEP | Byrdak | Demoted to reserve roster | | | Before |
| 8/6/2010 | NEP | Gregg | Promoted to active roster | | | Before |
| 8/6/2010 | SOI | Gimenez | Promoted to active roster | | | Before |
| 8/6/2010 | SOI | Lillibridge | Promoted to active roster | | | Before |
| 8/6/2010 | SOI | Pence | Demoted to reserve roster | | | Before |
| 8/6/2010 | SOI | Peralta,Jh | Demoted to reserve roster | | | Before |
| 8/7/2010 | BBG | Betemit | Demoted to reserve roster | | | Before |
| 8/7/2010 | BRK | DeJesus | Placed on Injured List | | 8/7/2010 | Before |
| 8/7/2010 | BRK | Heisey | Promoted to active roster | | | Before |
| 8/7/2010 | FDH | Parnell | Promoted to active roster | | | Before |
| 8/7/2010 | FDH | Stammen | Placed on Injured List | | 8/7/2010 | Before |
| 8/7/2010 | NEP | Harrell | Promoted to active roster | | | Before |
| 8/7/2010 | NEP | Thayer | Demoted to reserve roster | | | Before |
| 8/7/2010 | TEW | Callaspo | Promoted to active roster | | | Before |
| 8/7/2010 | TEW | Rodriguez,A | Placed on Injured List | | 8/6/2010 | Before |
| 8/8/2010 | CIN | Fowler | Demoted to reserve roster | | | Before |
| 8/8/2010 | CIN | Molina,B | Promoted to active roster | | | Before |
| 8/8/2010 | GAR | Turner | Demoted to reserve roster | | | Before |
| 8/9/2010 | AST | Kuroda | Demoted to reserve roster | | | Before |
| 8/9/2010 | AST | Sonnanstine | Promoted to active roster | | | Before |
| 8/9/2010 | BAR | Pedroia | Activated from Injured List | | | Before |
| 8/9/2010 | CIO | Bailey,A | Demoted to reserve roster | | | Before |
| 8/9/2010 | CIO | Doubront | Promoted to active roster | | | Before |
| 8/9/2010 | CTW | Carmona | Demoted to reserve roster | | | Before |
| 8/9/2010 | CTW | Cust | Demoted to reserve roster | | | Before |
| 8/9/2010 | CTW | Kuo | Promoted to active roster | | | Before |
| 8/9/2010 | CTW | Soriano,R | Promoted to active roster | | | Before |
| 8/9/2010 | FDH | Affeldt | Demoted to reserve roster | | | Before |
| 8/10/2010 | CIN | Bloomquist | Promoted to active roster | | | Before |
| 8/10/2010 | CIN | Frandsen | Demoted to reserve roster | | | Before |
| 8/10/2010 | CSS | Blanco,G | Demoted to reserve roster | | | Before |
| 8/10/2010 | CSS | Braun | Promoted to active roster | | | Before |
| 8/10/2010 | HAR | Cabrera,Mi | Demoted to reserve roster | | | Before |
| 8/10/2010 | HAR | Cashner | Demoted to reserve roster | | | Before |
| 8/10/2010 | HAR | Chavez,E | Promoted to active roster | | | Before |
| 8/10/2010 | HAR | Davis,D | Promoted to active roster | | | Before |
| 8/10/2010 | HAR | Murphy,Da | Promoted to active roster | | | Before |
| 8/10/2010 | HAR | Nava | Demoted to reserve roster | | | Before |
| 8/11/2010 | BAR | Correia | Promoted to active roster | | | Before |
| 8/11/2010 | BAR | Hawkins | Promoted to active roster | | | Before |
| 8/11/2010 | BAR | Reyes,Jo | Demoted to reserve roster | | | Before |
| 8/11/2010 | BAR | Romero,R | Demoted to reserve roster | | | Before |
| 8/11/2010 | BAR | Torres,C | Demoted to reserve roster | | | Before |
| 8/11/2010 | BAR | Torres,C | Promoted to active roster | | | Before |
| 8/11/2010 | BAR | Torres,C | Demoted to reserve roster | | | Before |
| 8/11/2010 | CBB | Hill,K | Demoted to reserve roster | | | Before |
| 8/11/2010 | CBB | Kelly | Promoted to active roster | | | Before |
| 8/11/2010 | CBB | Spilborghs | Promoted to active roster | | | Before |
| 8/11/2010 | CBB | Tabata | Demoted to reserve roster | | | Before |
| 8/11/2010 | CIO | Doubront | Demoted to reserve roster | | | Before |
| 8/11/2010 | CIO | Drew,JD | Promoted to active roster | | | Before |
| 8/11/2010 | CIO | Loe | Promoted to active roster | | | Before |
| 8/11/2010 | CIO | Mather | Demoted to reserve roster | | | Before |
| 8/11/2010 | CIO | Morel | Demoted to reserve roster | | | Before |
| 8/11/2010 | CIO | Wells,C | Promoted to active roster | | | Before |
| 8/11/2010 | NEP | Detwiler | Promoted to active roster | | | Before |
| 8/11/2010 | NEP | Jurrjens | Demoted to reserve roster | | | Before |
| 8/11/2010 | RMO | Moeller | Demoted to reserve roster | | | Before |
| 8/11/2010 | RMO | Ramirez,Max | Promoted to active roster | | | Before |
| 8/12/2010 | ATM | Robertson,D | Demoted to reserve roster | | | Before |
| 8/12/2010 | ATM | Rodriguez,I | Promoted to active roster | | | Before |
| 8/12/2010 | BBG | Betemit | Promoted to active roster | | | Before |
| 8/12/2010 | BBG | Luebke | Demoted to reserve roster | | | Before |
| 8/12/2010 | BBG | Montero | Demoted to reserve roster | | | Before |
| 8/12/2010 | BBG | Olivo | Activated from Injured List | | | Before |
| 8/12/2010 | BBG | Peralta,Jo | Promoted to active roster | | | Before |
| 8/12/2010 | CIN | Blum | Promoted to active roster | | | Before |
| 8/12/2010 | CIN | Cairo | Demoted to reserve roster | | | Before |
| 8/12/2010 | GAR | Grudzielanek | Promoted to active roster | | | Before |
| 8/12/2010 | GAR | Kouzmanoff | Placed on Injured List | | 8/12/2010 | Before |
| 8/12/2010 | NEP | McGehee | Promoted to active roster | | | Before |
| 8/12/2010 | NEP | Viciedo | Demoted to reserve roster | | | Before |
| 8/12/2010 | NYD | Aardsma | Promoted to active roster | | | Before |
| 8/12/2010 | NYD | Farnsworth | Demoted to reserve roster | | | Before |
| 8/12/2010 | TEW | Martinez,C | Promoted to active roster | | | Before |
| 8/12/2010 | TEW | Meek | Demoted to reserve roster | | | Before |
| 8/13/2010 | CIN | Crisp | Demoted to reserve roster | | | Before |
| 8/13/2010 | CIN | Hairston,J | Promoted to active roster | | | Before |
| 8/13/2010 | CIO | Cousins | Promoted to active roster | | | Before |
| 8/13/2010 | CIO | Kirkman | Promoted to active roster | | | Before |
| 8/13/2010 | CIO | McClendon | Demoted to reserve roster | | | Before |
| 8/13/2010 | CIO | Pagan | Placed on Injured List | | 8/13/2010 | Before |
| 8/13/2010 | SOI | Beckett | Promoted to active roster | | | Before |
| 8/13/2010 | SOI | Longoria | Demoted to reserve roster | | | Before |
| 8/13/2010 | SOI | Paulino,F | Promoted to active roster | | | Before |
| 8/13/2010 | SOI | Perez,R | Demoted to reserve roster | | | Before |
| 8/13/2010 | TEW | Adams | Promoted to active roster | | | Before |
| 8/13/2010 | TEW | Janssen | Demoted to reserve roster | | | Before |
| 8/14/2010 | BRK | Braddock | Demoted to reserve roster | | | Before |
| 8/14/2010 | TEW | Estrada | Promoted to active roster | | | Before |
| 8/14/2010 | TEW | Latos | Placed on Injured List | | 8/14/2010 | Before |
| 8/16/2010 | BRK | Sanches | Promoted to active roster | | | Before |
| 8/16/2010 | CIO | Cousins | Demoted to reserve roster | | | Before |
| 8/16/2010 | CIO | Mather | Promoted to active roster | | | Before |
| 8/16/2010 | GAR | Cruz,J | Demoted to reserve roster | | | Before |
| 8/17/2010 | GAR | Arrieta | Demoted to reserve roster | | | Before |
| 8/17/2010 | GAR | LeBlanc | Promoted to active roster | | | Before |
| 8/17/2010 | GAR | Mahay | Demoted to reserve roster | | | Before |
| 8/17/2010 | GAR | Moyer | Promoted to active roster | | | Before |
| 8/17/2010 | GAR | Park | Promoted to active roster | | | Before |
| 8/17/2010 | GAR | Sheets | Demoted to reserve roster | | | Before |
| 8/17/2010 | GAR | Suppan | Promoted to active roster | | | Before |
| 8/17/2010 | NEP | Harrell | Demoted to reserve roster | | | Before |
| 8/17/2010 | NEP | Wuertz | Promoted to active roster | | | Before |
| 8/18/2010 | BBG | Betancourt,R | Promoted to active roster | | | Before |
| 8/18/2010 | BBG | Kennedy,I | Demoted to reserve roster | | | Before |
| 8/18/2010 | CIN | Saltalamacchia | Promoted to active roster | | | Before |
| 8/18/2010 | CIN | Young,E | Placed on Injured List | | 8/18/2010 | Before |
| 8/18/2010 | NEP | Kratz | Promoted to active roster | | | Before |
| 8/18/2010 | NEP | Ransom | Demoted to reserve roster | | | Before |
| 8/18/2010 | SOI | MacDougal | Demoted to reserve roster | | | Before |
| 8/18/2010 | SOI | Mendoza | Promoted to active roster | | | Before |
| 8/19/2010 | ATM | Blanco,H | Promoted to active roster | | | Before |
| 8/19/2010 | ATM | Rodriguez,I | Demoted to reserve roster | | | Before |
| 8/19/2010 | CBB | Davis,W | Demoted to reserve roster | | | Before |
| 8/19/2010 | CBB | Hill,K | Promoted to active roster | | | Before |
| 8/19/2010 | FDH | Cash | Activated from Injured List | | | Before |
| 8/19/2010 | FDH | Cruz,L | Demoted to reserve roster | | | Before |
| 8/19/2010 | NEP | Russell,J | Demoted to reserve roster | | | Before |
| 8/19/2010 | NEP | Rzepczynski | Promoted to active roster | | | Before |
| 8/20/2010 | AST | Descalso | Promoted to active roster | | | Before |
| 8/20/2010 | AST | Salazar | Demoted to reserve roster | | | Before |
| 8/20/2010 | CIN | Alvarez | Promoted to active roster | | | Before |
| 8/20/2010 | CIN | Hairston,J | Placed on Injured List | | 8/20/2010 | Before |
| 8/20/2010 | CSS | Blanco,G | Promoted to active roster | | | Before |
| 8/20/2010 | CSS | Brantley | Placed on Injured List | | 8/18/2010 | Before |
| 8/20/2010 | CSS | Buehrle | Demoted to reserve roster | | | Before |
| 8/20/2010 | CSS | Buehrle | Promoted to active roster | | | Before |
| 8/20/2010 | CSS | Cishek | Demoted to reserve roster | | | Before |
| 8/20/2010 | CSS | Cishek | Promoted to active roster | | | Before |
| 8/20/2010 | CSS | Conrad | Promoted to active roster | | | Before |
| 8/20/2010 | CSS | Fuentes | Demoted to reserve roster | | | Before |
| 8/20/2010 | CSS | Fuentes | Promoted to active roster | | | Before |
| 8/20/2010 | CSS | Helms | Demoted to reserve roster | | | Before |
| 8/20/2010 | CSS | Keppinger | Demoted to reserve roster | | | Before |
| 8/20/2010 | CSS | Keppinger | Promoted to active roster | | | Before |
| 8/20/2010 | CSS | Maybin | Demoted to reserve roster | | | Before |
| 8/20/2010 | CSS | Maybin | Promoted to active roster | | | Before |
| 8/20/2010 | CSS | McDonald,Jo | Promoted to active roster | | | Before |
| 8/20/2010 | CSS | Punto | Demoted to reserve roster | | | Before |
| 8/20/2010 | CSS | Romero,JC | Demoted to reserve roster | | | Before |
| 8/20/2010 | CSS | Romero,JC | Promoted to active roster | | | Before |
| 8/20/2010 | CSS | Santiago | Activated from Injured List | | | Before |
| 8/20/2010 | CSS | Santiago | Demoted to reserve roster | | | Before |
| 8/20/2010 | CSS | Thompson,R | Demoted to reserve roster | | | Before |
| 8/20/2010 | CSS | Thompson,R | Promoted to active roster | | | Before |
| 8/21/2010 | CBB | Davis,W | Promoted to active roster | | | Before |
| 8/21/2010 | CBB | Hill,K | Demoted to reserve roster | | | Before |
| 8/21/2010 | CIO | Bartlett | Placed on Injured List | | 8/21/2010 | Before |
| 8/21/2010 | CIO | Morel | Promoted to active roster | | | Before |
| 8/21/2010 | CIO | Sogard | Demoted to reserve roster | | | Before |
| 8/21/2010 | CIO | Tolleson | Promoted to active roster | | | Before |
| 8/21/2010 | CSS | McDonald,Jo | Demoted to reserve roster | | | Before |
| 8/21/2010 | CSS | Santiago | Promoted to active roster | | | Before |
| 8/22/2010 | CIO | Kirkman | Demoted to reserve roster | | | Before |
| 8/22/2010 | CIO | Moreland | Promoted to active roster | | | Before |
| 8/22/2010 | CIO | Thornton | Promoted to active roster | | | Before |
| 8/22/2010 | CIO | Wells,C | Demoted to reserve roster | | | Before |
| 8/22/2010 | CTW | Chacin,J | Promoted to active roster | | | Before |
| 8/22/2010 | CTW | Kimbrel | Demoted to reserve roster | | | Before |
| 8/22/2010 | CTW | Santana,C | Promoted to active roster | | | Before |
| 8/22/2010 | CTW | Soriano,R | Demoted to reserve roster | | | Before |
| 8/22/2010 | FDH | Bailey,H | Activated from Injured List | | | Before |
| 8/22/2010 | FDH | Hamels | Demoted to reserve roster | | | Before |
| 8/22/2010 | FDH | Parnell | Demoted to reserve roster | | | Before |
| 8/22/2010 | FDH | Stammen | Activated from Injured List | | | Before |
| 8/22/2010 | TEW | Callaspo | Demoted to reserve roster | | | Before |
| 8/22/2010 | TEW | Rodriguez,A | Activated from Injured List | | | Before |
| 8/23/2010 | AST | Davies | Demoted to reserve roster | | | Before |
| 8/23/2010 | AST | Gaudin | Demoted to reserve roster | | | Before |
| 8/23/2010 | AST | Huff,D | Promoted to active roster | | | Before |
| 8/23/2010 | AST | Manuel | Promoted to active roster | | | Before |
| 8/23/2010 | CTW | Cust | Promoted to active roster | | | Before |
| 8/23/2010 | CTW | Santana,C | Demoted to reserve roster | | | Before |
| 8/24/2010 | BRK | DeJesus | Activated from Injured List | | | Before |
| 8/24/2010 | BRK | Heisey | Demoted to reserve roster | | | Before |
| 8/24/2010 | CIO | Denorfia | Promoted to active roster | | | Before |
| 8/24/2010 | CIO | Scott | Demoted to reserve roster | | | Before |
| 8/24/2010 | CTW | Kimbrel | Promoted to active roster | | | Before |
| 8/24/2010 | CTW | Stauffer | Demoted to reserve roster | | | Before |
| 8/24/2010 | HAR | Chavez,J | Placed on Injured List | | 8/24/2010 | Before |
| 8/24/2010 | HAR | Melancon | Promoted to active roster | | | Before |
| 8/24/2010 | NEP | Belisario | Promoted to active roster | | | Before |
| 8/24/2010 | NEP | Rauch | Demoted to reserve roster | | | Before |
| 8/24/2010 | NYD | Bell,H | Demoted to reserve roster | | | Before |
| 8/24/2010 | NYD | Billingsley | Placed on Injured List | | 8/24/2010 | Before |
| 8/24/2010 | NYD | Jenks | Activated from Injured List | | | Before |
| 8/24/2010 | NYD | Lewis,J | Demoted to reserve roster | | | Before |
| 8/24/2010 | NYD | Resop | Promoted to active roster | | | Before |
| 8/24/2010 | NYD | Rowand | Promoted to active roster | | | Before |
| 8/25/2010 | CIO | Conger | Promoted to active roster | | | Before |
| 8/25/2010 | CIO | Mauer | Demoted to reserve roster | | | Before |
| 8/25/2010 | CSS | Axford | Demoted to reserve roster | | | Before |
| 8/25/2010 | CSS | Lopez,Ja | Demoted to reserve roster | | | Before |
| 8/25/2010 | CSS | Marte,D | Promoted to active roster | | | Before |
| 8/25/2010 | CSS | Moylan | Demoted to reserve roster | | | Before |
| 8/25/2010 | CSS | Punto | Promoted to active roster | | | Before |
| 8/25/2010 | CSS | Putz | Promoted to active roster | | | Before |
| 8/25/2010 | CSS | Rollins | Demoted to reserve roster | | | Before |
| 8/25/2010 | CSS | Smith,Joe | Promoted to active roster | | | Before |
| 8/25/2010 | NEP | Belisario | Demoted to reserve roster | | | Before |
| 8/25/2010 | NEP | Harrell | Promoted to active roster | | | Before |
| 8/25/2010 | TEW | Inge | Demoted to reserve roster | | | Before |
| 8/25/2010 | TEW | Jay | Promoted to active roster | | | Before |
| 8/27/2010 | BAR | Lindstrom | Demoted to reserve roster | | | Before |
| 8/27/2010 | BAR | Walden | Promoted to active roster | | | Before |
| 8/27/2010 | BBG | Marshall | Promoted to active roster | | | Before |
| 8/27/2010 | BBG | Rivera,Ma | Demoted to reserve roster | | | Before |
| 8/27/2010 | CEN | Dickey | Placed on Injured List | | 8/24/2010 | Before |
| 8/27/2010 | CEN | Santos | Promoted to active roster | | | Before |
| 8/28/2010 | BAR | Correia | Placed on Injured List | | 8/28/2010 | Before |
| 8/28/2010 | BAR | Ramos,C | Promoted to active roster | | | Before |
| 8/28/2010 | BBG | Anderson,Bre | Promoted to active roster | | | Before |
| 8/28/2010 | BBG | Peralta,Jo | Demoted to reserve roster | | | Before |
| 8/28/2010 | CIN | Frieri | Promoted to active roster | | | Before |
| 8/28/2010 | CIN | Perez,C | Demoted to reserve roster | | | Before |
| 8/28/2010 | CIO | Mather | Demoted to reserve roster | | | Before |
| 8/28/2010 | CIO | Pagan | Activated from Injured List | | | Before |
| 8/29/2010 | CIN | Perkins | Promoted to active roster | | | Before |
| 8/29/2010 | CIN | Villanueva | Demoted to reserve roster | | | Before |
| 8/29/2010 | CTW | Lopez,W | Demoted to reserve roster | | | Before |
| 8/29/2010 | GAR | Duda | Demoted to reserve roster | | | Before |
| 8/29/2010 | RMO | Donald | Promoted to active roster | | | Before |
| 8/29/2010 | RMO | Encarnacion | Demoted to reserve roster | | | Before |
| 8/29/2010 | RMO | Galarraga | Promoted to active roster | | | Before |
| 8/29/2010 | RMO | Gardner | Demoted to reserve roster | | | Before |
| 8/29/2010 | RMO | Helton | Promoted to active roster | | | Before |
| 8/29/2010 | RMO | Rodriguez,FJ | Demoted to reserve roster | | | Before |
| 8/30/2010 | CIO | Burriss | Promoted to active roster | | | Before |
| 8/30/2010 | CIO | Hudson,D | Demoted to reserve roster | | | Before |
| 8/30/2010 | CIO | Santana,J | Promoted to active roster | | | Before |
| 8/30/2010 | CIO | Tolleson | Demoted to reserve roster | | | Before |
| 8/30/2010 | FDH | Cervelli | Demoted to reserve roster | | | Before |
| 8/30/2010 | FDH | Votto | Placed on Injured List | | 8/30/2010 | Before |
| 8/30/2010 | NEP | Kubel | Placed on Injured List | | 8/30/2010 | Before |
| 8/30/2010 | NEP | Thames | Promoted to active roster | | | Before |
| 8/30/2010 | RMO | Phillips,P | Promoted to active roster | | | Before |
| 8/30/2010 | RMO | Quiroz | Demoted to reserve roster | | | Before |
| 8/31/2010 | DLM | Bumgarner | Placed on Injured List | | 8/28/2010 | Before |
| 8/31/2010 | DLM | Pineiro | Activated from Injured List | | | Before |
| 9/1/2010 | AST | Belliard | Promoted to active roster | | | Before |
| 9/1/2010 | AST | Castillo,W | Activated from Injured List | | | Before |
| 9/1/2010 | AST | Craig | Promoted to active roster | | | Before |
| 9/1/2010 | AST | Davies | Promoted to active roster | | | Before |
| 9/1/2010 | AST | Donaldson | Promoted to active roster | | | Before |
| 9/1/2010 | AST | Fister | Promoted to active roster | | | Before |
| 9/1/2010 | AST | Gaudin | Promoted to active roster | | | Before |
| 9/1/2010 | AST | Gomez,J | Promoted to active roster | | | Before |
| 9/1/2010 | AST | Kuroda | Promoted to active roster | | | Before |
| 9/1/2010 | AST | Lugo | Promoted to active roster | | | Before |
| 9/1/2010 | AST | Nickeas | Promoted to active roster | | | Before |
| 9/1/2010 | AST | Richard | Promoted to active roster | | | Before |
| 9/1/2010 | AST | Salazar | Promoted to active roster | | | Before |
| 9/1/2010 | AST | Sardinha | Promoted to active roster | | | Before |
| 9/1/2010 | AST | Ziegler | Promoted to active roster | | | Before |
| 9/1/2010 | ATM | Napoli | Demoted to reserve roster | | | Before |
| 9/1/2010 | ATM | Nix,L | Promoted to active roster | | | Before |
| 9/1/2010 | BBG | Aceves | Promoted to active roster | | | Before |
| 9/1/2010 | BBG | De Aza | Promoted to active roster | | | Before |
| 9/1/2010 | BBG | Downs,M | Promoted to active roster | | | Before |
| 9/1/2010 | BBG | Gload | Promoted to active roster | | | Before |
| 9/1/2010 | BBG | Humber | Promoted to active roster | | | Before |
| 9/1/2010 | BBG | Jansen | Promoted to active roster | | | Before |
| 9/1/2010 | BBG | Kennedy,I | Promoted to active roster | | | Before |
| 9/1/2010 | BBG | Mayberry | Promoted to active roster | | | Before |
| 9/1/2010 | BBG | Montero | Promoted to active roster | | | Before |
| 9/1/2010 | BBG | Valdez,W | Promoted to active roster | | | Before |
| 9/1/2010 | BBG | Zito | Promoted to active roster | | | Before |
| 9/1/2010 | BRK | Pena,R | Promoted to active roster | | | Before |
| 9/1/2010 | BRK | Russell,A | Promoted to active roster | | | Before |
| 9/1/2010 | CEN | Bray | Promoted to active roster | | | Before |
| 9/1/2010 | CEN | Castro,R | Promoted to active roster | | | Before |
| 9/1/2010 | CEN | Fuld | Promoted to active roster | | | Before |
| 9/1/2010 | CEN | Howard | Promoted to active roster | | | Before |
| 9/1/2010 | CEN | Maldonado | Promoted to active roster | | | Before |
| 9/1/2010 | CEN | Morrison | Promoted to active roster | | | Before |
| 9/1/2010 | CEN | Soria | Promoted to active roster | | | Before |
| 9/1/2010 | CIN | Arencibia | Promoted to active roster | | | Before |
| 9/1/2010 | CIN | Elbert | Promoted to active roster | | | Before |
| 9/1/2010 | CIN | Frandsen | Promoted to active roster | | | Before |
| 9/1/2010 | CIN | Jennings | Promoted to active roster | | | Before |
| 9/1/2010 | CIN | Kottaras | Promoted to active roster | | | Before |
| 9/1/2010 | CIN | LeCure | Promoted to active roster | | | Before |
| 9/1/2010 | CIN | Logan | Promoted to active roster | | | Before |
| 9/1/2010 | CIN | Miller,C | Promoted to active roster | | | Before |
| 9/1/2010 | CIN | Pena,B | Promoted to active roster | | | Before |
| 9/1/2010 | CIN | Simon | Promoted to active roster | | | Before |
| 9/1/2010 | CIN | Trumbo | Promoted to active roster | | | Before |
| 9/1/2010 | CIN | Willingham | Promoted to active roster | | | Before |
| 9/1/2010 | CIO | Doubront | Promoted to active roster | | | Before |
| 9/1/2010 | CIO | Duncan | Promoted to active roster | | | Before |
| 9/1/2010 | CIO | Germano | Demoted to reserve roster | | | Before |
| 9/1/2010 | CIO | Mather | Promoted to active roster | | | Before |
| 9/1/2010 | CIO | McClendon | Promoted to active roster | | | Before |
| 9/1/2010 | CIO | Petersen | Promoted to active roster | | | Before |
| 9/1/2010 | CIO | Wells,C | Promoted to active roster | | | Before |
| 9/1/2010 | CSS | Bourgeois | Promoted to active roster | | | Before |
| 9/1/2010 | CSS | Cain,L | Promoted to active roster | | | Before |
| 9/1/2010 | CSS | Flowers | Promoted to active roster | | | Before |
| 9/1/2010 | CSS | Jeffress | Promoted to active roster | | | Before |
| 9/1/2010 | CSS | Lopez,Ja | Promoted to active roster | | | Before |
| 9/1/2010 | CSS | Moylan | Promoted to active roster | | | Before |
| 9/1/2010 | CSS | Webb | Promoted to active roster | | | Before |
| 9/1/2010 | CTW | Badenhop | Promoted to active roster | | | Before |
| 9/1/2010 | CTW | Barajas | Promoted to active roster | | | Before |
| 9/1/2010 | CTW | Carmona | Promoted to active roster | | | Before |
| 9/1/2010 | CTW | Colvin | Promoted to active roster | | | Before |
| 9/1/2010 | CTW | Everett | Promoted to active roster | | | Before |
| 9/1/2010 | CTW | Fox,J | Promoted to active roster | | | Before |
| 9/1/2010 | CTW | Hernandez,R | Promoted to active roster | | | Before |
| 9/1/2010 | CTW | Johnson,C | Promoted to active roster | | | Before |
| 9/1/2010 | CTW | Joyce | Promoted to active roster | | | Before |
| 9/1/2010 | CTW | Masset | Promoted to active roster | | | Before |
| 9/1/2010 | CTW | Moss | Promoted to active roster | | | Before |
| 9/1/2010 | CTW | O'Day | Promoted to active roster | | | Before |
| 9/1/2010 | CTW | Soriano,R | Promoted to active roster | | | Before |
| 9/1/2010 | CTW | Young,Delm | Promoted to active roster | | | Before |
| 9/1/2010 | DLM | Alonso | Promoted to active roster | | | Before |
| 9/1/2010 | DLM | Anderson,Bry | Promoted to active roster | | | Before |
| 9/1/2010 | DLM | DeWitt | Promoted to active roster | | | Before |
| 9/1/2010 | DLM | Frasor | Promoted to active roster | | | Before |
| 9/1/2010 | DLM | Lannan | Promoted to active roster | | | Before |
| 9/1/2010 | DLM | Lee,D | Promoted to active roster | | | Before |
| 9/1/2010 | DLM | Lewis,F | Promoted to active roster | | | Before |
| 9/1/2010 | DLM | Lowe,M | Promoted to active roster | | | Before |
| 9/1/2010 | DLM | Lucroy | Demoted to reserve roster | | | Before |
| 9/1/2010 | DLM | Mijares | Promoted to active roster | | | Before |
| 9/1/2010 | DLM | Miller,T | Demoted to reserve roster | | | Before |
| 9/1/2010 | DLM | Qualls | Promoted to active roster | | | Before |
| 9/1/2010 | DLM | Redmond | Promoted to active roster | | | Before |
| 9/1/2010 | DLM | Rivera,J | Promoted to active roster | | | Before |
| 9/1/2010 | DLM | Smith,S | Promoted to active roster | | | Before |
| 9/1/2010 | DLM | Wilson,Bo | Promoted to active roster | | | Before |
| 9/1/2010 | FDH | Cervelli | Promoted to active roster | | | Before |
| 9/1/2010 | FDH | Cruz,L | Promoted to active roster | | | Before |
| 9/1/2010 | FDH | Hardy | Promoted to active roster | | | Before |
| 9/1/2010 | FDH | Jepsen | Promoted to active roster | | | Before |
| 9/1/2010 | FDH | Lohse | Demoted to reserve roster | | | Before |
| 9/1/2010 | FDH | Tomlin | Promoted to active roster | | | Before |
| 9/1/2010 | NYD | Fontenot | Promoted to active roster | | | Before |
| 9/1/2010 | NYD | Gillespie | Promoted to active roster | | | Before |
| 9/1/2010 | NYD | Kalish | Promoted to active roster | | | Before |
| 9/1/2010 | NYD | Lucy | Promoted to active roster | | | Before |
| 9/1/2010 | NYD | Morales,J | Promoted to active roster | | | Before |
| 9/1/2010 | NYD | Sutton | Promoted to active roster | | | Before |
| 9/1/2010 | RMO | Figgins | Promoted to active roster | | | Before |
| 9/1/2010 | RMO | Maier | Promoted to active roster | | | Before |
| 9/1/2010 | RMO | Monasterios | Promoted to active roster | | | Before |
| 9/1/2010 | SOI | Andino | Promoted to active roster | | | Before |
| 9/1/2010 | SOI | Avila | Promoted to active roster | | | Before |
| 9/1/2010 | SOI | Bonifacio | Demoted to reserve roster | | | Before |
| 9/1/2010 | SOI | Downs,S | Promoted to active roster | | | Before |
| 9/1/2010 | SOI | Espinosa | Promoted to active roster | | | Before |
| 9/1/2010 | SOI | Hellickson | Promoted to active roster | | | Before |
| 9/1/2010 | SOI | MacDougal | Promoted to active roster | | | Before |
| 9/1/2010 | SOI | Perez,R | Promoted to active roster | | | Before |
| 9/1/2010 | SOI | Valverde | Promoted to active roster | | | Before |
| 9/1/2010 | TEW | Belisle | Promoted to active roster | | | Before |
| 9/1/2010 | TEW | Borbon | Promoted to active roster | | | Before |
| 9/1/2010 | TEW | Callaspo | Promoted to active roster | | | Before |
| 9/1/2010 | TEW | Estrada | Demoted to reserve roster | | | Before |
| 9/1/2010 | TEW | Guzman | Promoted to active roster | | | Before |
| 9/1/2010 | TEW | Inge | Promoted to active roster | | | Before |
| 9/1/2010 | TEW | Jaramillo | Promoted to active roster | | | Before |
| 9/1/2010 | TEW | Meek | Promoted to active roster | | | Before |
| 9/1/2010 | TEW | Mora | Promoted to active roster | | | Before |
| 9/1/2010 | TEW | Ondrusek | Promoted to active roster | | | Before |
| 9/1/2010 | TEW | Overbay | Promoted to active roster | | | Before |
| 9/1/2010 | TEW | Patton | Promoted to active roster | | | Before |
| 9/1/2010 | TEW | Paulino,R | Promoted to active roster | | | Before |
| 9/1/2010 | TEW | Sanabia | Promoted to active roster | | | Before |
| 9/1/2010 | TEW | Schumaker | Promoted to active roster | | | Before |
| 9/2/2010 | AST | Donaldson | Demoted to reserve roster | | | Before |
| 9/2/2010 | CTW | Kuo | Demoted to reserve roster | | | Before |
| 9/2/2010 | CTW | Posey | Demoted to reserve roster | | | Before |
| 9/2/2010 | GAR | Ankiel | Promoted to active roster | | | Before |
| 9/2/2010 | GAR | Arrieta | Promoted to active roster | | | Before |
| 9/2/2010 | GAR | Ausmus | Promoted to active roster | | | Before |
| 9/2/2010 | GAR | Castro,S | Activated from Injured List | | | Before |
| 9/2/2010 | GAR | Dyson | Promoted to active roster | | | Before |
| 9/2/2010 | GAR | Hoffman | Promoted to active roster | | | Before |
| 9/2/2010 | GAR | Kouzmanoff | Activated from Injured List | | | Before |
| 9/2/2010 | GAR | Madson | Promoted to active roster | | | Before |
| 9/2/2010 | GAR | Mahay | Promoted to active roster | | | Before |
| 9/2/2010 | GAR | Manship | Promoted to active roster | | | Before |
| 9/2/2010 | GAR | Saunders,M | Promoted to active roster | | | Before |
| 9/2/2010 | GAR | Stairs | Promoted to active roster | | | Before |
| 9/2/2010 | GAR | Turner | Promoted to active roster | | | Before |
| 9/2/2010 | GAR | Wakefield | Promoted to active roster | | | Before |
| 9/2/2010 | GAR | Winn | Promoted to active roster | | | Before |
| 9/3/2010 | BAR | Hester | Demoted to reserve roster | | | Before |
| 9/3/2010 | BAR | Shoppach | Activated from Injured List | | | Before |
| 9/3/2010 | CIN | Cairo | Promoted to active roster | | | Before |
| 9/3/2010 | CIO | Mauer | Promoted to active roster | | | Before |
| 9/3/2010 | CSS | Brantley | Activated from Injured List | | | Before |
| 9/3/2010 | FDH | Ramos,W | Promoted to active roster | | | Before |
| 9/4/2010 | AST | McLouth | Promoted to active roster | | | Before |
| 9/4/2010 | BBG | Aceves | Demoted to reserve roster | | | Before |
| 9/4/2010 | BRK | Gwynn | Promoted to active roster | | | Before |
| 9/4/2010 | BRK | Heisey | Promoted to active roster | | | Before |
| 9/4/2010 | BRK | Langerhans | Promoted to active roster | | | Before |
| 9/4/2010 | BRK | Pagnozzi | Promoted to active roster | | | Before |
| 9/4/2010 | BRK | Pie | Promoted to active roster | | | Before |
| 9/4/2010 | BRK | Repko | Promoted to active roster | | | Before |
| 9/4/2010 | BRK | Schneider | Promoted to active roster | | | Before |
| 9/4/2010 | CEN | Jones,C | Promoted to active roster | | | Before |
| 9/4/2010 | CIN | Hairston,J | Activated from Injured List | | | Before |
| 9/4/2010 | CSS | Marcum | Activated from Injured List | | | Before |
| 9/4/2010 | FDH | Carrasco,C | Demoted to reserve roster | | | Before |
| 9/4/2010 | GAR | Bradley | Demoted to reserve roster | | | Before |
| 9/4/2010 | SOI | MacDougal | Demoted to reserve roster | | | Before |
| 9/4/2010 | SOI | Young,CR | Demoted to reserve roster | | | Before |
| 9/4/2010 | TEW | Patton | Demoted to reserve roster | | | Before |
| 9/5/2010 | CIN | Fowler | Promoted to active roster | | | Before |
| 9/5/2010 | CIN | Vargas,J | Placed on Injured List | | 9/5/2010 | Before |
| 9/5/2010 | CIN | Young,E | Activated from Injured List | | | Before |
| 9/5/2010 | CIO | Tolleson | Promoted to active roster | | | Before |
| 9/6/2010 | ATM | Damon | Promoted to active roster | | | Before |
| 9/6/2010 | ATM | Werth | Demoted to reserve roster | | | Before |
| 9/6/2010 | CIO | Bartlett | Activated from Injured List | | | Before |
| 9/6/2010 | CIO | Conger | Demoted to reserve roster | | | Before |
| 9/6/2010 | CSS | Conrad | Demoted to reserve roster | | | Before |
| 9/6/2010 | CTW | Buchholz,C | Demoted to reserve roster | | | Before |
| 9/8/2010 | CIO | Bailey,A | Promoted to active roster | | | Before |
| 9/8/2010 | CIO | Mather | Demoted to reserve roster | | | Before |
| 9/8/2010 | CIO | Raburn | Demoted to reserve roster | | | Before |
| 9/8/2010 | CIO | Scott | Promoted to active roster | | | Before |
| 9/8/2010 | CIO | Thornton | Demoted to reserve roster | | | Before |
| 9/8/2010 | CIO | Tolleson | Demoted to reserve roster | | | Before |
| 9/8/2010 | CTW | Morneau | Demoted to reserve roster | | | Before |
| 9/8/2010 | HAR | Holland,D | Promoted to active roster | | | Before |
| 9/8/2010 | HAR | Melancon | Demoted to reserve roster | | | Before |
| 9/8/2010 | NEP | Harrell | Demoted to reserve roster | | | Before |
| 9/8/2010 | NEP | Morrow | Promoted to active roster | | | Before |
| 9/8/2010 | RMO | Brown,Du | Promoted to active roster | | | Before |
| 9/8/2010 | RMO | Ramirez,Max | Placed on Injured List | | 9/7/2010 | Before |
| 9/8/2010 | SOI | Wilson,Ja | Demoted to reserve roster | | | Before |
| 9/9/2010 | AST | Gomez,J | Placed on Injured List | | 9/5/2010 | Before |
| 9/9/2010 | AST | Lowrie | Promoted to active roster | | | Before |
| 9/9/2010 | ATM | Holland,G | Demoted to reserve roster | | | Before |
| 9/9/2010 | CEN | Guerrier | Demoted to reserve roster | | | Before |
| 9/9/2010 | CIN | Frieri | Demoted to reserve roster | | | Before |
| 9/9/2010 | CSS | Smith,Joe | Demoted to reserve roster | | | Before |
| 9/9/2010 | FDH | Gomez,C | Demoted to reserve roster | | | Before |
| 9/9/2010 | SOI | Andino | Demoted to reserve roster | | | Before |
| 9/9/2010 | SOI | Granderson | Promoted to active roster | | | Before |
| 9/9/2010 | SOI | Lillibridge | Demoted to reserve roster | | | Before |
| 9/9/2010 | SOI | Pence | Promoted to active roster | | | Before |
| 9/9/2010 | SOI | Peralta,Jh | Promoted to active roster | | | Before |
| 9/10/2010 | ATM | Brignac | Promoted to active roster | | | Before |
| 9/10/2010 | ATM | League | Promoted to active roster | | | Before |
| 9/10/2010 | CEN | Dickey | Activated from Injured List | | | Before |
| 9/10/2010 | CEN | Maldonado | Demoted to reserve roster | | | Before |
| 9/10/2010 | CSS | Putz | Demoted to reserve roster | | | Before |
| 9/10/2010 | CTW | Bruce | Demoted to reserve roster | | | Before |
| 9/10/2010 | CTW | Morales,K | Demoted to reserve roster | | | Before |
| 9/10/2010 | CTW | Saito | Demoted to reserve roster | | | Before |
| 9/10/2010 | CTW | Venable | Demoted to reserve roster | | | Before |
| 9/10/2010 | GAR | Park | Demoted to reserve roster | | | Before |
| 9/10/2010 | GAR | Rodney | Promoted to active roster | | | Before |
| 9/10/2010 | TEW | Gregerson | Demoted to reserve roster | | | Before |
| 9/12/2010 | CIO | Acosta | Promoted to active roster | | | Before |
| 9/12/2010 | CIO | Bailey,A | Demoted to reserve roster | | | Before |
| 9/12/2010 | FDH | Bailey,H | Demoted to reserve roster | | | Before |
| 9/12/2010 | FDH | Ellis,AJ | Promoted to active roster | | | Before |
| 9/12/2010 | FDH | Salas | Promoted to active roster | | | Before |
| 9/12/2010 | HAR | Chavez,E | Demoted to reserve roster | | | Before |
| 9/12/2010 | HAR | Chavez,J | Activated from Injured List | | | Before |
| 9/12/2010 | HAR | Navarro,D | Promoted to active roster | | | Before |
| 9/12/2010 | SOI | Bastardo | Demoted to reserve roster | | | Before |
| 9/12/2010 | SOI | Cabrera,Me | Demoted to reserve roster | | | Before |
| 9/12/2010 | SOI | Longoria | Promoted to active roster | | | Before |
| 9/12/2010 | SOI | Mendoza | Demoted to reserve roster | | | Before |
| 9/12/2010 | SOI | Patterson,C | Signed | | | Before |
| 9/12/2010 | TEW | Adams | Demoted to reserve roster | | | Before |
| 9/13/2010 | AST | Tallet | Demoted to reserve roster | | | Before |
| 9/13/2010 | ATM | Holliday | Demoted to reserve roster | | | Before |
| 9/13/2010 | BAR | Choate | Demoted to reserve roster | | | Before |
| 9/13/2010 | BAR | Choate | Promoted to active roster | | | Before |
| 9/13/2010 | BAR | Correia | Activated from Injured List | | | Before |
| 9/13/2010 | BAR | Escalona | Promoted to active roster | | | Before |
| 9/13/2010 | BAR | Hawkins | Demoted to reserve roster | | | Before |
| 9/13/2010 | BAR | Morales,F | Demoted to reserve roster | | | Before |
| 9/13/2010 | BAR | Morgan | Demoted to reserve roster | | | Before |
| 9/13/2010 | BAR | Varvaro | Promoted to active roster | | | Before |
| 9/13/2010 | CEN | Burrell | Demoted to reserve roster | | | Before |
| 9/13/2010 | CIN | Elbert | Demoted to reserve roster | | | Before |
| 9/13/2010 | CIN | Perkins | Demoted to reserve roster | | | Before |
| 9/13/2010 | CIO | Bogusevic | Promoted to active roster | | | Before |
| 9/13/2010 | CIO | Rhymes | Demoted to reserve roster | | | Before |
| 9/13/2010 | NYD | Billingsley | Activated from Injured List | | | Before |
| 9/13/2010 | SOI | Sandoval | Demoted to reserve roster | | | Before |
| 9/13/2010 | TEW | Latos | Activated from Injured List | | | Before |
| 9/14/2010 | BBG | Hanigan | Demoted to reserve roster | | | Before |
| 9/14/2010 | BRK | Balfour | Demoted to reserve roster | | | Before |
| 9/14/2010 | BRK | Gonzalez,M | Promoted to active roster | | | Before |
| 9/14/2010 | BRK | Lidge | Promoted to active roster | | | Before |
| 9/14/2010 | CIO | Hudson,D | Promoted to active roster | | | Before |
| 9/14/2010 | CIO | Wilson,Br | Demoted to reserve roster | | | Before |
| 9/14/2010 | CTW | Lyon | Demoted to reserve roster | | | Before |
| 9/14/2010 | CTW | Moss | Demoted to reserve roster | | | Before |
| 9/14/2010 | HAR | Strop | Promoted to active roster | | | Before |
| 9/14/2010 | SOI | Leake | Demoted to reserve roster | | | Before |
| 9/15/2010 | BBG | Johnson,Jo | Demoted to reserve roster | | | Before |
| 9/15/2010 | BBG | Johnson,Ro | Promoted to active roster | | | Before |
| 9/15/2010 | CBB | Franklin | Demoted to reserve roster | | | Before |
| 9/15/2010 | HAR | Strop | Demoted to reserve roster | | | Before |
| 9/15/2010 | SOI | Espinosa | Demoted to reserve roster | | | Before |
| 9/16/2010 | AST | Huff,D | Demoted to reserve roster | | | Before |
| 9/16/2010 | CIO | Hudson,D | Demoted to reserve roster | | | Before |
| 9/16/2010 | NEP | Baxter | Promoted to active roster | | | Before |
| 9/16/2010 | SOI | Francis | Placed on Injured List | | 9/10/2010 | Before |
| 9/16/2010 | SOI | Hellickson | Demoted to reserve roster | | | Before |
| 9/17/2010 | BBG | Tulowitzki | Demoted to reserve roster | | | Before |
| 9/17/2010 | CIO | Hoover | Promoted to active roster | | | Before |
| 9/17/2010 | CIO | Ross,D | Demoted to reserve roster | | | Before |
| 9/17/2010 | CIO | Scott | Demoted to reserve roster | | | Before |
| 9/17/2010 | CSS | Braun | Demoted to reserve roster | | | Before |
| 9/17/2010 | CSS | Mathis,J | Promoted to active roster | | | Before |
| 9/17/2010 | CSS | Ruiz,C | Demoted to reserve roster | | | Before |
| 9/17/2010 | CSS | Utley | Demoted to reserve roster | | | Before |
| 9/18/2010 | BBG | Pujols | Demoted to reserve roster | | | Before |
| 9/18/2010 | HAR | Davis,D | Demoted to reserve roster | | | Before |
| 9/18/2010 | NEP | Breslow | Demoted to reserve roster | | | Before |
| 9/19/2010 | BRK | Chamberlain | Promoted to active roster | | | Before |
| 9/19/2010 | BRK | Coke | Promoted to active roster | | | Before |
| 9/19/2010 | BRK | Hill,Sh | Promoted to active roster | | | Before |
| 9/19/2010 | BRK | Perry | Promoted to active roster | | | Before |
| 9/19/2010 | BRK | Wood,K | Promoted to active roster | | | Before |
| 9/19/2010 | CIN | Alvarez | Demoted to reserve roster | | | Before |
| 9/19/2010 | CSS | Jeffress | Demoted to reserve roster | | | Before |
| 9/19/2010 | CTW | Marmol | Demoted to reserve roster | | | Before |
| 9/19/2010 | FDH | Ellis,AJ | Promoted to active roster | | | Before |
| 9/19/2010 | GAR | Manship | Demoted to reserve roster | | | Before |
| 9/19/2010 | GAR | Neshek | Promoted to active roster | | | Before |
| 9/19/2010 | HAR | Nava | Promoted to active roster | | | Before |
| 9/19/2010 | HAR | Rowland-Smith | Demoted to reserve roster | | | Before |
| 9/19/2010 | HAR | Samardzija | Promoted to active roster | | | Before |
| 9/19/2010 | HAR | Zimmermann | Promoted to active roster | | | Before |
| 9/21/2010 | AST | Richard | Demoted to reserve roster | | | Before |
| 9/21/2010 | BBG | Humber | Demoted to reserve roster | | | Before |
| 9/21/2010 | CIN | Vargas,J | Activated from Injured List | | | Before |
| 9/21/2010 | CTW | O'Day | Demoted to reserve roster | | | Before |
| 9/21/2010 | HAR | Powell | Demoted to reserve roster | | | Before |
| 9/21/2010 | NEP | Kubel | Activated from Injured List | | | Before |
| 9/21/2010 | NYD | Gonzalez,Ad | Demoted to reserve roster | | | Before |
| 9/22/2010 | AST | Gomez,J | Activated from Injured List | | | Before |
| 9/22/2010 | BAR | Morales,F | Promoted to active roster | | | Before |
| 9/22/2010 | BAR | Ramos,C | Demoted to reserve roster | | | Before |
| 9/22/2010 | BRK | Zimmerman | Demoted to reserve roster | | | Before |
| 9/22/2010 | CTW | Jimenez | Demoted to reserve roster | | | Before |
| 9/22/2010 | CTW | Saito | Promoted to active roster | | | Before |
| 9/22/2010 | HAR | Cashner | Promoted to active roster | | | Before |
| 9/22/2010 | HAR | Castro,Ja | Promoted to active roster | | | Before |
| 9/22/2010 | HAR | Parra,G | Demoted to reserve roster | | | Before |
| 9/22/2010 | RMO | Hatcher | Promoted to active roster | | | Before |
| 9/22/2010 | RMO | Phillips,P | Demoted to reserve roster | | | Before |
| 9/22/2010 | RMO | Schmidt | Promoted to active roster | | | Before |
| 9/22/2010 | RMO | St. Pierre | Promoted to active roster | | | Before |
| 9/23/2010 | BAR | Kelley | Promoted to active roster | | | Before |
| 9/23/2010 | BAR | Minor | Promoted to active roster | | | Before |
| 9/23/2010 | BAR | Torres,C | Promoted to active roster | | | Before |
| 9/23/2010 | BAR | Veras | Demoted to reserve roster | | | Before |
| 9/23/2010 | BBG | Betancourt,R | Demoted to reserve roster | | | Before |
| 9/23/2010 | CBB | Capps | Demoted to reserve roster | | | Before |
| 9/23/2010 | CIN | Logan | Demoted to reserve roster | | | Before |
| 9/23/2010 | CIO | Morel | Demoted to reserve roster | | | Before |
| 9/23/2010 | HAR | Feliz,P | Demoted to reserve roster | | | Before |
| 9/23/2010 | NEP | Baxter | Demoted to reserve roster | | | Before |
| 9/23/2010 | NYD | Rolen | Demoted to reserve roster | | | Before |
| 9/24/2010 | BAR | Boesch | Demoted to reserve roster | | | Before |
| 9/24/2010 | BBG | Oliver,D | Demoted to reserve roster | | | Before |
| 9/24/2010 | BRK | Ramirez,H | Demoted to reserve roster | | | Before |
| 9/24/2010 | CEN | Revere | Demoted to reserve roster | | | Before |
| 9/24/2010 | CIN | Young,E | Demoted to reserve roster | | | Before |
| 9/24/2010 | CIO | Burriss | Demoted to reserve roster | | | Before |
| 9/24/2010 | CIO | Sogard | Promoted to active roster | | | Before |
| 9/24/2010 | HAR | Casilla,S | Promoted to active roster | | | Before |
| 9/24/2010 | HAR | Holland,D | Demoted to reserve roster | | | Before |
| 9/24/2010 | HAR | Sale | Promoted to active roster | | | Before |
| 9/24/2010 | HAR | Samardzija | Demoted to reserve roster | | | Before |
| 9/24/2010 | HAR | Wood,Tr | Promoted to active roster | | | Before |
| 9/24/2010 | NYD | Swisher | Demoted to reserve roster | | | Before |
| 9/25/2010 | BAR | Escalona | Demoted to reserve roster | | | Before |
| 9/25/2010 | CSS | Batista | Promoted to active roster | | | Before |
| 9/25/2010 | CSS | Cain,L | Demoted to reserve roster | | | Before |
| 9/25/2010 | CSS | Flowers | Demoted to reserve roster | | | Before |
| 9/25/2010 | CSS | Helms | Promoted to active roster | | | Before |
| 9/25/2010 | CSS | Hernandez,Li | Promoted to active roster | | | Before |
| 9/25/2010 | CSS | Hinske | Promoted to active roster | | | Before |
| 9/25/2010 | CSS | McDonald,Jo | Promoted to active roster | | | Before |
| 9/25/2010 | CTW | Johnson,K | Demoted to reserve roster | | | Before |
| 9/25/2010 | DLM | Lowe,M | Demoted to reserve roster | | | Before |
| 9/25/2010 | FDH | Salas | Promoted to active roster | | | Before |
| 9/25/2010 | FDH | Tomlin | Demoted to reserve roster | | | Before |
| 9/25/2010 | FDH | Votto | Activated from Injured List | | | Before |
| 9/25/2010 | HAR | Cabrera,Mi | Promoted to active roster | | | Before |
| 9/25/2010 | HAR | Hochevar | Demoted to reserve roster | | | Before |
| 9/25/2010 | NYD | Cano | Demoted to reserve roster | | | Before |
| 9/25/2010 | SOI | Sanchez,Ang | Signed | | | Before |
| 9/25/2010 | TEW | Meek | Demoted to reserve roster | | | Before |
| 9/26/2010 | AST | Wood,Br | Demoted to reserve roster | | | Before |
| 9/26/2010 | ATM | Young,CB | Demoted to reserve roster | | | Before |
| 9/26/2010 | BRK | Hernandez,Lu | Promoted to active roster | | | Before |
| 9/26/2010 | CBB | Johnson,N | Promoted to active roster | | | Before |
| 9/26/2010 | CBB | Matsui,H | Promoted to active roster | | | Before |
| 9/26/2010 | CIO | Burriss | Promoted to active roster | | | Before |
| 9/26/2010 | CIO | Padilla | Promoted to active roster | | | Before |
| 9/26/2010 | CIO | Raburn | Promoted to active roster | | | Before |
| 9/26/2010 | CIO | Ross,D | Promoted to active roster | | | Before |
| 9/26/2010 | CIO | Sogard | Demoted to reserve roster | | | Before |
| 9/26/2010 | CIO | Tolleson | Promoted to active roster | | | Before |
| 9/26/2010 | HAR | Cashner | Demoted to reserve roster | | | Before |
| 9/26/2010 | HAR | Iwamura | Demoted to reserve roster | | | Before |
| 9/26/2010 | NYD | Mitre | Demoted to reserve roster | | | Before |