Mariners Roster & Staff
Transactions
| Date | Transaction |
| 07/31/15 | Seattle Mariners recalled Jose Ramirez from Tacoma Rainiers. |
| 07/31/15 | Seattle Mariners recalled SS Ketel Marte from Tacoma Rainiers. |
| 07/31/15 | Seattle Mariners traded RHP Mark Lowe to Toronto Blue Jays for LHP Rob Rasmussen, LHP Jake Brentz and LHP Nick Wells. |
| 07/31/15 | Seattle Mariners traded RHP Mark Lowe to Toronto Blue Jays for LHP Rob Rasmussen, LHP Jake Brentz and LHP Nick Wells. |
| 07/31/15 | Seattle Mariners traded RHP Mark Lowe to Toronto Blue Jays for LHP Rob Rasmussen, LHP Jake Brentz and LHP Nick Wells. |
| 07/31/15 | Seattle Mariners traded RHP Mark Lowe to Toronto Blue Jays for LHP Rob Rasmussen, LHP Jake Brentz and LHP Nick Wells. |
| 07/31/15 | Seattle Mariners traded LHP J.A. Happ to Pittsburgh Pirates for RHP Adrian Sampson. |
| 07/31/15 | Seattle Mariners optioned SS Chris Taylor to Tacoma Rainiers. |
| 07/31/15 | Seattle Mariners traded LHP J.A. Happ to Pittsburgh Pirates for RHP Adrian Sampson. |
| 07/30/15 | Seattle Mariners traded LF Dustin Ackley to New York Yankees for RHP Jose Ramirez and LF Ramon Flores. |
| 07/30/15 | Seattle Mariners traded LF Dustin Ackley to New York Yankees for RHP Jose Ramirez and LF Ramon Flores. |
| 07/30/15 | Seattle Mariners traded LF Dustin Ackley to New York Yankees for RHP Jose Ramirez and LF Ramon Flores. |
| 07/30/15 | Seattle Mariners optioned RHP Jose Ramirez to Tacoma Rainiers. |
| 07/30/15 | Seattle Mariners optioned LF Ramon Flores to Tacoma Rainiers. |
| 07/30/15 | Seattle Mariners recalled Jesus Montero from Tacoma Rainiers. |
| 07/21/15 | Seattle Mariners signed free agent 3B Aderlin Rodriguez to a minor league contract. |
| 07/20/15 | Seattle Mariners recalled LHP J.A. Happ from Bakersfield Blaze. |
| 07/20/15 | Seattle Mariners optioned 1B Jesus Montero to Tacoma Rainiers. |
| 07/17/15 | Seattle Mariners recalled RHP Tom Wilhelmsen from Tacoma Rainiers. |
| 07/13/15 | Seattle Mariners optioned RHP Danny Farquhar to Tacoma Rainiers. |
| 07/11/15 | Seattle Mariners signed free agent RHP Chien-Ming Wang to a minor league contract. |
| 07/09/15 | Seattle Mariners optioned LHP J.A. Happ to Bakersfield Blaze. |
| 07/09/15 | Seattle Mariners recalled LHP Vidal Nuno from Tacoma Rainiers. |
| 07/09/15 | Seattle Mariners placed LHP Charlie Furbush on the 15-day disabled list retroactive to July 8, 2015. Left biceps tendinitis |
| 07/09/15 | Seattle Mariners recalled Danny Farquhar from Tacoma Rainiers. |
| 07/09/15 | Seattle Mariners recalled Jesus Montero from Tacoma Rainiers. |
| 07/09/15 | Seattle Mariners optioned RHP Mayckol Guaipe to Tacoma Rainiers. |
| 07/06/15 | Seattle Mariners optioned CF James Jones to Tacoma Rainiers. |
| 07/06/15 | Seattle Mariners released SS Willie Bloomquist. |
| 07/06/15 | Seattle Mariners activated RHP Hisashi Iwakuma from the 15-day disabled list. |
| 07/04/15 | Seattle Mariners sent Julio Morban outright to Jackson Generals. |
| 07/04/15 | David Rollins roster status changed by Seattle Mariners. |
| 07/04/15 | Seattle Mariners recalled James Jones from Tacoma Rainiers. |
| 07/04/15 | Seattle Mariners recalled Mayckol Guaipe from Tacoma Rainiers. |
| 07/04/15 | Seattle Mariners optioned LHP Roenis Elias to Tacoma Rainiers. |
| 07/04/15 | Seattle Mariners optioned LHP Vidal Nuno to Tacoma Rainiers. |
| 07/04/15 | Seattle Mariners optioned RHP Tom Wilhelmsen to Tacoma Rainiers. |
| 07/03/15 | Seattle Mariners signed free agent 3B Nolan Perez to a minor league contract. |
| 07/02/15 | Seattle Mariners signed free agent RHP Andy Taveras to a minor league contract. |
| 07/02/15 | Seattle Mariners signed free agent SS Carlos Vargas to a minor league contract. |
| 07/02/15 | Seattle Mariners signed free agent C Daniel Santos to a minor league contract. |
| 07/02/15 | Seattle Mariners recalled Chris Taylor from Tacoma Rainiers. |
| 07/02/15 | Seattle Mariners designated SS Willie Bloomquist for assignment. |
| 07/02/15 | Seattle Mariners optioned RF Julio Morban to Jackson Generals. |
| 07/02/15 | Seattle Mariners signed free agent RHP Ivan Fortunato to a minor league contract. |
| 07/02/15 | Seattle Mariners signed free agent C Erik Kratz to a minor league contract. |