Mariners Roster & Staff
Transactions
| Date | Transaction |
| 07/07/26 | Seattle Mariners signed free agent RHP Mario Vasquez to a minor league contract. |
| 07/07/26 | CF Stuart Fairchild assigned to ACL Mariners from Seattle Mariners. |
| 07/05/26 | CF Stuart Fairchild roster status changed by Seattle Mariners. |
| 07/05/26 | Seattle Mariners signed free agent CF Stuart Fairchild to a minor league contract. |
| 07/03/26 | Seattle Mariners placed CF Julio Rodríguez on the 7-day injured list. Concussion. |
| 07/03/26 | Seattle Mariners transferred RHP Cooper Criswell from the 15-day injured list to the 60-day injured list. Right shoulder strain. |
| 07/03/26 | Seattle Mariners selected the contract of 3B Miles Mastrobuoni from Tacoma Rainiers. |