| Date | Player | Pos. | Transaction |
| 7/21 | Oscar Villarreal | P | Signed to a Minor League Contract |
| 7/20 | J.J. Putz | P | Removed From 15-Day DL, (Hyperextended right elbow) |
| 7/20 | J.J. Putz | P | Recalled From Minors, Rehab Assignment |
| 7/20 | Ryan Rowland-Smith | P | Sent to Minors |
| 7/18 | Bryan LaHair | 1B | Called Up from Minors |
| 7/17 | Tug Hulett | 2B | Sent to Minors |
| 7/13 | J.J. Putz | P | Sent to Minors, For Rehabilitation |
| 7/11 | Jared Wells | P | Sent to Minors |
| 7/11 | Jason Kershner | P | Signed to a Minor League Contract |
| 7/11 | Randy Messenger | P | Signed to a Minor League Contract |
| 7/11 | Felix Hernandez | P | Removed From 15-Day DL, (Sprained left ankle) |
| 7/10 | Erik Bedard | P | Placed on 15-Day DL, (Left shoulder stiffness) |
| 7/10 | Richie Sexson | 1B | Released |
| 7/10 | Jared Wells | P | Called Up from Minors |
| 7/10 | Craig Wilson | 1B | Traded From, Pittsburgh (for player to be named) |
| 7/9 | Anderson Garcia | P | Released |
| 7/1 | Cesar Jimenez | P | Called Up from Minors |
| 6/30 | Felix Hernandez | P | Placed on 15-Day DL, (Sprained left ankle) |
| 6/17 | Wladimir Balentien | RF | Sent to Minors |
| 6/17 | Jeff Clement | C | Called Up from Minors |
| 6/15 | Scott Williamson | P | Signed to a Minor League Contract |
| 6/13 | Roy Corcoran | P | Called Up from Minors |
| 6/13 | J.J. Putz | P | Placed on 15-Day DL, (Hyperextended right elbow) |
| 5/28 | Anderson Garcia | P | Sent to Minors |
| 5/28 | Anderson Garcia | P | Removed From 15-Day DL, (Right shoulder tendinitis) |
| 5/28 | Anderson Garcia | P | Recalled From Minors, Rehab Assignment |
| 5/22 | R.A. Dickey | P | Called Up from Minors |
| 5/21 | Cha Seung Baek | P | Designated for Assignment |
| 5/19 | Jeremy Reed | LF | Called Up from Minors |
| 5/18 | Jeff Clement | C | Sent to Minors |
| 5/16 | Richie Sexson | 1B | Reinstated From League Suspension |
| 5/10 | Richie Sexson | 1B | Starting to Serve Suspension |
| 5/9 | Richie Sexson | 1B | Suspension Announced By League, (five games) |
| 5/8 | Brad Wilkerson | RF | Cleared Waivers and Became a Free Agent |
| 4/30 | Greg Norton | 1B | Designated for Assignment |
| 4/30 | Wladimir Balentien | CF | Called Up from Minors |
| 4/30 | Brad Wilkerson | RF | Designated for Assignment |
| 4/30 | Jeff Clement | C | Called Up from Minors |
| 4/26 | Roy Corcoran | P | Sent to Minors |
| 4/26 | Erik Bedard | P | Removed From 15-Day DL, (Left hip inflammation) |
| 4/25 | Kenji Johjima | C | Signed, ( 2008-2011)(three-year extension) |
| 4/22 | R.A. Dickey | P | Sent to Minors |
| 4/22 | J.J. Putz | P | Removed From 15-Day DL, (Right torso inflammation) |
| 4/19 | Anderson Garcia | P | Sent to Minors, For Rehabilitation |
| 4/16 | Charlton Jimerson | RF | Signed to a Minor League Contract |
| 4/16 | Brandon Morrow | P | Called Up from Minors |
| 4/16 | Charlton Jimerson | RF | Released |
| 4/15 | Erik Bedard | P | Placed on 15-Day DL, (Left hip inflammation) |
| 4/14 | Mike Morse | 1B | Placed on 15-Day DL, (Dislocated left shoulder) |
| 4/14 | Eric O'Flaherty | P | Sent to Minors |
| 4/14 | Arthur Rhodes | P | Purchased From Minors |
| 4/14 | R.A. Dickey | P | Called Up from Minors |
| 4/11 | Greg Norton | RF | Purchased From Minors |
| 4/11 | Charlton Jimerson | RF | Designated for Assignment |
| 4/2 | J.J. Putz | P | Placed on 15-Day DL, (Right torso inflammation) |
| 4/2 | Roy Corcoran | P | Purchased From Minors |
| 3/30 | Anderson Garcia | P | Placed on 15-Day DL, (Right shoulder tendinitis) |
| 3/26 | Ryan Feierabend | P | Sent to Minors |
| 3/25 | Kevin Witt | 1B | Signed to a Minor League Contract |
| 3/24 | Wladimir Balentien | CF | Sent to Minors |
| 3/24 | Rob Johnson | C | Sent to Minors |
| 3/19 | Jeff Clement | C | Sent to Minors |
| 3/19 | Cesar Jimenez | P | Sent to Minors |
| 3/19 | Sean White | P | Sent to Minors |
| 3/19 | Jon Huber | P | Sent to Minors |
| 3/12 | Horacio Ramirez | P | Released |
| 3/8 | Bubba Crosby | CF | Released |
| 3/8 | Denny Stark | | Signed to a Minor League Contract |
| 2/23 | Mike Kinkade | 1B | Signed to a Minor League Contract |
| 2/19 | Bubba Crosby | CF | Signed to a Minor League Contract |
| 2/16 | Anderson Garcia | P | Acquired Off Waivers From, Philadelphia |
| 2/15 | Erik Bedard | P | Signed, ( 2008)(avoids arbitration) |
| 2/13 | Greg Norton | RF | Signed to a Minor League Contract |
| 2/8 | Erik Bedard | P | Traded From, Baltimore (for OF Adam Jones in six-player deal) |
| 1/31 | Brad Wilkerson | 1B | Signed as Free Agent, ( 2008) |
| More Transactions |
| Posted Wed Jul 23 22:32:43 EDT 2008 |
