| DATE | PLAYER | DESCRIPTION |
| 05/20/2012 | Lance Berkman | Placed on 15-day disabled list |
|
05/20/2012 | Matt Adams | Contract purchased from Memphis (AAA) |
|
05/18/2012 | Allen Craig | Placed on 15-day disabled list |
|
05/18/2012 | Kyle McClellan | Placed on 15-day disabled list |
|
05/18/2012 | Brandon Dickson | Recalled from Memphis (AAA) |
|
05/18/2012 | Adron Chambers | Recalled from Memphis (AAA) |
|
05/15/2012 | Shane Robinson | Recalled from Memphis (AAA) |
|
05/15/2012 | Jon Jay | Placed on 15-day disabled list |
|
05/14/2012 | Eduardo Sanchez | Recalled from Memphis (AAA) |
|
05/14/2012 | J.C. Romero | Released |
|
05/13/2012 | Lance Berkman | Activated from 15-day disabled list |
|
05/13/2012 | Shane Robinson | Optioned to Memphis (AAA) |
|
05/01/2012 | Allen Craig | Activated from 15-day disabled list |
|
05/01/2012 | Erik Komatsu | Designated for assignment |