Nationals Roster & Staff
Transactions
| Date | Transaction |
| 07/31/21 | Washington Nationals activated RHP Mason Thompson. |
| 07/30/21 | Washington Nationals traded RHP Daniel Hudson to San Diego Padres for RHP Mason Thompson. |
| 07/30/21 | St. Louis Cardinals traded CF Lane Thomas to Washington Nationals for LHP Jon Lester. |
| 07/30/21 | Washington Nationals traded RHP Daniel Hudson to San Diego Padres for RHP Mason Thompson. |
| 07/30/21 | St. Louis Cardinals traded CF Lane Thomas to Washington Nationals for LHP Jon Lester. |
| 07/30/21 | Washington Nationals selected the contract of 3B Adrian Sanchez from Rochester Red Wings. |
| 07/30/21 | Washington Nationals recalled C Tres Barrera from Rochester Red Wings. |
| 07/30/21 | Washington Nationals selected the contract of RHP Gabe Klobosits from Rochester Red Wings. |
| 07/30/21 | Washington Nationals signed SS Jordy Barley. |
| 07/30/21 | Washington Nationals traded C Yan Gomes, 2B Josh Harrison and cash to Oakland Athletics for RHP Richard Guasch, RHP Seth Shuman and C Drew Millas. |
| 07/30/21 | Washington Nationals traded C Yan Gomes, 2B Josh Harrison and cash to Oakland Athletics for RHP Richard Guasch, RHP Seth Shuman and C Drew Millas. |
| 07/30/21 | Washington Nationals traded C Yan Gomes, 2B Josh Harrison and cash to Oakland Athletics for RHP Richard Guasch, RHP Seth Shuman and C Drew Millas. |
| 07/30/21 | Washington Nationals traded C Yan Gomes, 2B Josh Harrison and cash to Oakland Athletics for RHP Richard Guasch, RHP Seth Shuman and C Drew Millas. |
| 07/30/21 | Washington Nationals traded C Yan Gomes, 2B Josh Harrison and cash to Oakland Athletics for RHP Richard Guasch, RHP Seth Shuman and C Drew Millas. |
| 07/30/21 | Washington Nationals traded RHP Max Scherzer and SS Trea Turner to Los Angeles Dodgers for C Keibert Ruiz, RHP Josiah Gray, RHP Gerardo Carrillo and OF Donovan Casey. |
| 07/30/21 | Washington Nationals traded RHP Max Scherzer and SS Trea Turner to Los Angeles Dodgers for C Keibert Ruiz, RHP Josiah Gray, RHP Gerardo Carrillo and OF Donovan Casey. |
| 07/30/21 | Washington Nationals traded RHP Max Scherzer and SS Trea Turner to Los Angeles Dodgers for C Keibert Ruiz, RHP Josiah Gray, RHP Gerardo Carrillo and OF Donovan Casey. |
| 07/30/21 | Washington Nationals traded RHP Max Scherzer and SS Trea Turner to Los Angeles Dodgers for C Keibert Ruiz, RHP Josiah Gray, RHP Gerardo Carrillo and OF Donovan Casey. |
| 07/30/21 | Washington Nationals traded RHP Max Scherzer and SS Trea Turner to Los Angeles Dodgers for C Keibert Ruiz, RHP Josiah Gray, RHP Gerardo Carrillo and OF Donovan Casey. |
| 07/30/21 | Washington Nationals traded RHP Max Scherzer and SS Trea Turner to Los Angeles Dodgers for C Keibert Ruiz, RHP Josiah Gray, RHP Gerardo Carrillo and OF Donovan Casey. |
| 07/30/21 | Washington Nationals optioned C Tres Barrera to Rochester Red Wings. |
| 07/30/21 | Washington Nationals signed SS Brady House. |
| 07/29/21 | Washington Nationals placed SS Trea Turner on the 10-day injured list. |
| 07/29/21 | Washington Nationals recalled RHP Andres Machado, , , and from Rochester Red Wings. |
| 07/29/21 | Washington Nationals optioned C Tres Barrera to Rochester Red Wings. |
| 07/29/21 | Washington Nationals placed RHP Austin Voth on the 10-day injured list. |
| 07/29/21 | Washington Nationals placed C Alex Avila on the 10-day injured list. |
| 07/29/21 | Washington Nationals activated RHP Tanner Rainey. |
| 07/29/21 | Washington Nationals traded LHP Brad Hand to Toronto Blue Jays for C Riley Adams. |
| 07/29/21 | Washington Nationals placed RHP Daniel Hudson on the 10-day injured list. |
| 07/29/21 | Washington Nationals recalled OF Yadiel Hernandez from Rochester Red Wings. |
| 07/29/21 | Washington Nationals traded LHP Brad Hand to Toronto Blue Jays for C Riley Adams. |
| 07/29/21 | Washington Nationals activated C Yan Gomes from the 10-day injured list. |
| 07/29/21 | Washington Nationals traded LF Kyle Schwarber to Boston Red Sox for RHP Aldo Ramirez. |
| 07/29/21 | Washington Nationals traded LF Kyle Schwarber to Boston Red Sox for RHP Aldo Ramirez. |
| 07/29/21 | Washington Nationals recalled SS Luis Garcia from Rochester Red Wings. |
| 07/29/21 | Washington Nationals recalled C Tres Barrera from Rochester Red Wings. |
| 07/28/21 | Washington Nationals optioned C Tres Barrera to Rochester Red Wings. |
| 07/26/21 | Washington Nationals activated RHP Joe Ross from the 10-day injured list. |
| 07/26/21 | Washington Nationals optioned OF Yadiel Hernandez to Rochester Red Wings. |
| 07/25/21 | Washington Nationals sent RHP Tanner Rainey on a rehab assignment to Rochester Red Wings. |
| 07/24/21 | Washington Nationals recalled SS Carter Kieboom from Rochester Red Wings. |
| 07/24/21 | Washington Nationals placed SS Jordy Mercer on the 10-day injured list. Left calf strain. |
| 07/23/21 | Washington Nationals signed OF Daylen Lile. |
| 07/22/21 | Washington Nationals signed free agent RHP Carlos Navas to a minor league contract. |
| 07/20/21 | Washington Nationals signed free agent LHP Matt Tomshaw to a minor league contract. |
| 07/19/21 | Washington Nationals signed OF Jaden Fein. |
| 07/19/21 | Washington Nationals recalled LF Andrew Stevenson from Rochester Red Wings. |
| 07/19/21 | Washington Nationals signed OF Jacob Young. |
| 07/19/21 | Washington Nationals signed RHP Jack Sinclair. |
| 07/19/21 | Washington Nationals optioned RHP Andres Machado to Rochester Red Wings. |
| 07/19/21 | Washington Nationals signed OF T.J. White. |
| 07/19/21 | Washington Nationals optioned LF Andrew Stevenson to Rochester Red Wings. |
| 07/19/21 | Washington Nationals signed C Cole Hamilton. |
| 07/19/21 | Washington Nationals signed C Jarrett Gonzales. |
| 07/18/21 | Washington Nationals recalled LF Andrew Stevenson from Rochester Red Wings. |
| 07/18/21 | Washington Nationals signed free agent 2B RobertAnthony Cruz to a minor league contract. |
| 07/16/21 | Washington Nationals signed free agent C Rene Rivera. |
| 07/16/21 | Washington Nationals optioned C Jakson Reetz to Rochester Red Wings. |
| 07/16/21 | Washington Nationals activated SS Jordy Mercer from the 10-day injured list. |
| 07/16/21 | Washington Nationals placed SS Starlin Castro on the restricted list. |
| 07/15/21 | Washington Nationals signed OF Branden Boissiere. |
| 07/15/21 | Washington Nationals signed RHP Cole Quintanilla. |
| 07/15/21 | Washington Nationals signed LHP Michael Kirian. |
| 07/14/21 | Washington Nationals signed free agent LHP Juan Diaz to a minor league contract. |
| 07/13/21 | Washington Nationals traded LHP Kyle Lobstein to Milwaukee Brewers for cash. |
| 07/13/21 | Washington Nationals signed free agent C Juan Paulino to a minor league contract. |
| 07/12/21 | Washington Nationals signed free agent RHP Bryan Polanco to a minor league contract. |
| 07/12/21 | Washington Nationals signed free agent RHP Adrian Ogando to a minor league contract. |
| 07/11/21 | Washington Nationals recalled RHP Andres Machado from Rochester Red Wings. |
| 07/11/21 | Washington Nationals placed RHP Kyle McGowin on the 10-day injured list. |
| 07/10/21 | Washington Nationals placed C Yan Gomes on the 10-day injured list. Oblique strain. |
| 07/10/21 | Washington Nationals designated LHP Kyle Lobstein for assignment. |
| 07/10/21 | Washington Nationals selected the contract of C Jakson Reetz from Rochester Red Wings. |
| 07/09/21 | Washington Nationals optioned LF Andrew Stevenson to Rochester Red Wings. |
| 07/09/21 | Washington Nationals activated LF Andrew Stevenson. |
| 07/09/21 | Washington Nationals signed free agent 2B Derek Dietrich to a minor league contract. |
| 07/08/21 | Washington Nationals placed RHP Joe Ross on the 10-day injured list. Right elbow inflammation. |
| 07/08/21 | Washington Nationals recalled RHP Ryne Harper from Rochester Red Wings. |
| 07/07/21 | Washington Nationals activated RHP Daniel Hudson from the 10-day injured list. |
| 07/07/21 | Washington Nationals optioned RHP Andres Machado to Rochester Red Wings. |
| 07/06/21 | Washington Nationals activated RHP Erick Fedde from the 10-day injured list. |
| 07/06/21 | Washington Nationals optioned LHP Kyle Lobstein to Rochester Red Wings. |
| 07/06/21 | Washington Nationals activated RHP Kyle Finnegan from the 10-day injured list. |
| 07/06/21 | Washington Nationals optioned RHP Ryne Harper to Rochester Red Wings. |
| 07/06/21 | Washington Nationals signed free agent RHP Nick Goody to a minor league contract. |
| 07/05/21 | Washington Nationals sent SS Humberto Arteaga outright to Rochester Red Wings. |
| 07/04/21 | Washington Nationals signed free agent RHP Diego Moreno to a minor league contract. |
| 07/04/21 | Washington Nationals sent LF Andrew Stevenson on a rehab assignment to Rochester Red Wings. |
| 07/03/21 | Washington Nationals recalled OF Yadiel Hernandez from Rochester Red Wings. |
| 07/03/21 | Washington Nationals placed LF Kyle Schwarber on the 10-day injured list. Right hamstring strain. |
| 07/03/21 | Washington Nationals recalled C Tres Barrera from Rochester Red Wings. |
| 07/03/21 | Washington Nationals placed C Alex Avila on the 10-day injured list. Bilateral calf strains. |
| 07/03/21 | Washington Nationals designated SS Humberto Arteaga for assignment. |
| 07/03/21 | Washington Nationals selected the contract of SS Alcides Escobar, , , and from Rochester Red Wings. |
| 07/03/21 | Kansas City Royals traded SS Alcides Escobar to Washington Nationals for cash. |
| 07/03/21 | OF Jeremy Ydens assigned to Washington Nationals from Fredericksburg Nationals. |
| 07/02/21 | Washington Nationals selected the contract of SS Humberto Arteaga from Rochester Red Wings. |
| 07/02/21 | St. Louis Cardinals claimed RHP Justin Miller off waivers from Washington Nationals. |
| 07/02/21 | Washington Nationals placed RHP Steven Fuentes on the 60-day injured list. Right shoulder strain. |
| 07/02/21 | Washington Nationals recalled RHP Steven Fuentes from Rochester Red Wings. |
| 07/02/21 | Washington Nationals placed SS Jordy Mercer on the 10-day injured list. Right quad strain. |