| Year (affiliation) | Wins | Losses | Winning Pct. | GB (Division Standing) | Manager |
|---|
| 1987 (Pittsburgh Pirates) | 77 | 63 | .550 | -11 (2nd out of 8) | Dave Trembley |
| 1988 (Pittsburgh Pirates) | 65 | 73 | .471 | -15.5 (7th out of 8) | Dave Trembley |
| 1989 (Pittsburgh Pirates) | 71 | 65 | .522 | -19 (2nd out of 8) | Dave Trembley |
| 1990 (Pittsburgh Pirates) | 69 | 69 | .500 | -9.5 (5th out of 8) | Marc Bombard |
| 1991 (Montreal Expos) | 87 | 53 | .621 | +6 (1st out of 8) | Mike Quade |
| 1992 (Montreal Expos) | 78 | 59 | .569 | -1.5 (3rd out of 8) | Mike Quade |
| 1993 (Montreal Expos) | 94 | 44 | .681 | +19 (1st out of 8) | Jim Tracy |
| 1994 (Montreal Expos) | 88 | 51 | .633 | +5.5 (1st out of 5 in Southern Division) | Dave Jauss |
| 1995 (Montreal Expos) | 61 | 80 | .433 | -11.5 (5th out of 5 in Southern Division) | Pat Kelly |
| 1996 (Montreal Expos) | 74 | 68 | .521 | -12 (2nd out of 5 in Southern Division) | Pat Kelly |
| 1997 (Montreal Expos) | 86 | 56 | .606 | +11 (1st out of 5 in Southern Division) | Rick Sofield |
| 1998 (Montreal Expos) | 73 | 69 | .514 | -8.5 (2nd out of 5 in Southern Division) | Rick Sweet |
| 1999 (Montreal Expos) | 76 | 66 | .535 | -9.5 (2nd out of 6 in Southern Division) | Doug Sisson |
| 2000 (Montreal Expos) | 76 | 67 | .531 | -9.5 (2nd out of 6 in Southern Division) | Doug Sisson |
| 2001 (Montreal Expos) | 66 | 76 | .465 | -18 (4th out of 6 in Southern Division) | Luis Dorante |
| 2002 (Montreal Expos) | 79 | 63 | .556 | -14.5 (2nd out of 6 in Southern Division) | Dave Huppert |
| 2003 (Montreal Expos) | 60 | 82 | .423 | -28.5 (6th out of 6 in Southern Division) | Dave Machemer |
| 2004 (Montreal Expos) | 52 | 90 | .366 | -33.5 (6th out of 6 in Southern Division) | Dave Machemer |
| 2005 (Washington Nationals) | 64 | 78 | .451 | -20 (5th out of 6 in Southern Division) | Keith Bodie |
| 2006 (Washington Nationals) | 67 | 75 | .472 | -20 (5th out of 6 in Southern Division) | John Stearns |
| 2007 (Washington Nationals) | 55 | 86 | .390 | -26.5 (6th out of 6 in Southern Division) | Scott Little |
| 2008 (Washington Nationals) | 73 | 69 | .514 | -11 (3rd out of 6 in Southern Division) | John Stearns |
| 2009 (Washington Nationals) | 70 | 72 | .493 | -19 (5th out of 6 in Southern Division) | John Stearns |
| 2010 (Washington Nationals) | 77 | 65 | .542 | -5 (2nd out of 6 in Western Division) | Randy Knorr |
| 2011 (Washington Nationals) | 80 | 62 | .563 | +4 (1st out of 6 in Western Division) | Tony Beasley |
| 2012 (Washington Nationals) | 64 | 78 | .451 | -18.5 (5th out of 6 in Western Division) | Matthew LeCroy |
| 2013 (Washington Nationals) | 77 | 65 | .542 | +1 (1st out of 6 in Western Division) | Matthew LeCroy |
| 2014 (Washington Nationals) | 53 | 89 | .373 | -26 (6th out of 6 in Western Division) | Brian Daubach |
| 2015 (Washington Nationals) | 67 | 75 | .472 | -12 (5th out of 6 in Western Division) | Brian Daubach |
| 2016 (Washington Nationals) | 76 | 66 | .535 | -1.5 (3rd out of 6 in Western Division) | Matthew LeCroy |
| 2017 (Washington Nationals) | 60 | 80 | .429 | -14 (6th out of 6 in Western Division) | Matthew LeCroy |
| 2018 (Washington Nationals) | 72 | 65 | .526 | -5.5 (3rd out of 6 in Western Division) | Matthew LeCroy |
| 2019 (Washington Nationals) | 76 | 63 | .547 | -1.5 (2nd out of 6 in Western Division, 1st Half Division Winner) | Matthew LeCroy |
| 2021 (Washington Nationals) | 42 | 76 | .356 | −30.5 (6th out of 6 in Southwestern Division) | Tripp Keister |
| 2022 (Washington Nationals) | 52 | 85 | .380 | −27.5 (6th out of 6 in Southwestern Division) | Tripp Keister |
| 2023 (Washington Nationals) | 59 | 77 | .434 | −15.5 (6th out of 6 in Southwestern Division) | Delino DeShields |
| 2024 (Washington Nationals) | 68 | 70 | .493 | −12.0 (3rd out of 6 in Southwestern Division) | Delino DeShields |
| 2025 (Washington Nationals) | 68 | 70 | .493 | −16.0 (4th out of 6 in Southwestern Division) | Delino DeShields |
| CURRENT SENATORS TOTAL | 2652 | 2660 | .499 | | |
| ALL TIME TOTAL | 3412 | 3389 | .502 | | |