| Transactions | ||||||
| Date | Team | Player | Type | OthTm | EffDate | When |
| 4/11/1955 | Bal | Pillette | Placed on disabled list | Before | ||
| 4/11/1955 | Bos | Williams | Retired | Before | ||
| 4/13/1955 | NYA | Martin | Placed on restricted list | Before | ||
| 4/14/1955 | Bal | Wilson | Acquired via trade | Mil | Before | |
| 4/14/1955 | Bos | Bolling | Placed on disabled list | Before | ||
| 4/15/1955 | NYA | Noren | Suspended | Before | ||
| 4/16/1955 | ChA | Merriman | Traded away | ChN | Before | |
| 4/18/1955 | Bal | Leppert | Demoted to reserve roster | Before | ||
| 4/18/1955 | Bal | Stephens | Released | Before | ||
| 4/18/1955 | NYA | Noren | Reinstated | Before | ||
| 4/18/1955 | Was | Gonzales | Released | Before | ||
| 4/20/1955 | Bos | Consolo | Demoted to reserve roster | Before | ||
| 4/22/1955 | KC | MacKenzie | Promoted to active roster | Before | ||
| 4/22/1955 | NYA | Coleman | Placed on disabled list | After | ||
| 4/27/1955 | Det | Belardi | Demoted to reserve roster | Before | ||
| 4/28/1955 | KC | Raschi | Signed | Before | ||
| 4/28/1955 | KC | Sleater | Acquired via trade | NYA | Before | |
| 4/28/1955 | KC | Stewart | Demoted to reserve roster | Before | ||
| 4/28/1955 | KC | Van Brabant | Demoted to reserve roster | Before | ||
| 4/28/1955 | KC | Wheat | Demoted to reserve roster | Before | ||