Nationals Roster & Staff
Transactions
| Date | Transaction |
| 07/19/26 | Washington Nationals sent RHP Jake Irvin on a rehab assignment to Harrisburg Senators. |
| 07/19/26 | Washington Nationals sent RHP Trevor Williams on a rehab assignment to Wilmington Blue Rocks. |
| 07/19/26 | Washington Nationals transferred LHP Richard Lovelady from the 15-day injured list to the 60-day injured list. Left triceps strain. |
| 07/19/26 | Washington Nationals placed LHP PJ Poulin on the 15-day injured list retroactive to July 16, 2026. Left flexor strain. |
| 07/19/26 | Washington Nationals signed free agent LHP Matt Krook. |
| 07/17/26 | Washington Nationals optioned 1B Abimelec Ortiz to Rochester Red Wings. |
| 07/17/26 | Washington Nationals recalled C Harry Ford from Rochester Red Wings. |
| 07/16/26 | Washington Nationals traded CF Robert Hassell III to Pittsburgh Pirates for cash. |
| 07/15/26 | Washington Nationals placed C Drew Millas on the 10-day injured list retroactive to July 12, 2026. Left index finger fracture. |
| 07/15/26 | Washington Nationals activated RHP Max Kranick from the 60-day injured list. |
| 07/14/26 | Washington Nationals sent RHP Max Kranick on a rehab assignment to FCL Nationals. |
| 07/14/26 | Washington Nationals sent RHP Trevor Williams on a rehab assignment to FCL Nationals. |
| 07/14/26 | Washington Nationals sent LHP Matt Krook outright to Rochester Red Wings. |
| 07/13/26 | Washington Nationals sent RHP Jake Irvin on a rehab assignment to FCL Nationals. |
| 07/13/26 | Washington Nationals optioned 1B Abimelec Ortiz to Rochester Red Wings. |
| 07/12/26 | Washington Nationals designated LHP Matt Krook for assignment. |
| 07/12/26 | Washington Nationals activated RHP Cade Cavalli. |
| 07/12/26 | RHP Miles Mikolas suspended. |
| 07/12/26 | Washington Nationals recalled 1B Abimelec Ortiz from Rochester Red Wings. |
| 07/12/26 | Washington Nationals sent CF Robert Hassell III outright to Rochester Red Wings. |
| 07/11/26 | Detroit Tigers claimed RHP Andre Granillo off waivers from Washington Nationals. |
| 07/10/26 | Washington Nationals transferred RHP Jake Irvin from the 15-day injured list to the 60-day injured list. Right shoulder strain. |
| 07/10/26 | Washington Nationals selected the contract of LHP Tom Cosgrove from Rochester Red Wings. |
| 07/09/26 | Washington Nationals placed RHP Brad Lord on the 15-day injured list retroactive to July 6, 2026. Left side tightness. |
| 07/08/26 | Washington Nationals signed free agent 3B Devin Ortiz to a minor league contract. |
| 07/08/26 | Washington Nationals sent RHP Trevor Williams on a rehab assignment to Rochester Red Wings. |
| 07/07/26 | Washington Nationals activated LHP Matt Krook. |
| 07/07/26 | Washington Nationals optioned RHP Cole Henry to Rochester Red Wings. |
| 07/06/26 | RHP Cade Cavalli suspended. |
| 07/06/26 | Washington Nationals optioned RHP Eddy Yean to Rochester Red Wings. |
| 07/06/26 | Washington Nationals recalled RHP Cole Henry from Rochester Red Wings. |
| 07/05/26 | Washington Nationals designated CF Robert Hassell III for assignment. |
| 07/05/26 | Washington Nationals activated RHP Eddy Yean. |
| 07/05/26 | Washington Nationals activated RHP Eddy Yean. |
| 07/05/26 | SS Miguel Villarroel assigned to Washington Nationals. |
| 07/05/26 | Washington Nationals selected the contract of RHP Eddy Yean from Rochester Red Wings. |
| 07/05/26 | Washington Nationals optioned RHP Zak Kent to Rochester Red Wings. |
| 07/04/26 | Washington Nationals sent RHP Max Kranick on a rehab assignment to Rochester Red Wings. |
| 07/04/26 | Washington Nationals designated RHP Andre Granillo for assignment. |
| 07/04/26 | Washington Nationals sent RHP Max Kranick on a rehab assignment to Rochester Red Wings. |
| 07/04/26 | Washington Nationals sent RHP Max Kranick on a rehab assignment to Rochester Red Wings. |
| 07/04/26 | Washington Nationals claimed LHP Matt Krook off waivers from Athletics. |
| 07/03/26 | Washington Nationals signed free agent RHP John Valle to a minor league contract. |
| 07/03/26 | Washington Nationals sent RHP Max Kranick on a rehab assignment to Harrisburg Senators. |
| 07/03/26 | Washington Nationals sent RHP Trevor Williams on a rehab assignment to Harrisburg Senators. |
| 07/03/26 | Houston Astros traded LHP Tom Cosgrove to Washington Nationals for cash. |
| 07/02/26 | Washington Nationals signed free agent LHP Konnor Pilkington to a minor league contract. |
| 07/01/26 | Washington Nationals transferred LHP Mitchell Parker from the 15-day injured list to the 60-day injured list. Left elbow inflammation. |
| 07/01/26 | Baltimore Orioles traded RHP Kyle Nicolas to Washington Nationals for SS Randal Diaz. |
| 07/01/26 | Baltimore Orioles traded RHP Kyle Nicolas to Washington Nationals for SS Randal Diaz. |