Every Gillingham season on record, from 1912–13 to 2026–27 — league record, finishing position and leading scorer. Click a season for every match it contained.
| Season | Division | P | W | D | L | GF | GA | Pos | Leading scorer |
|---|---|---|---|---|---|---|---|---|---|
| 1912–13 | Southern League | 2 | 0 | 1 | 1 | 1 | 3 | 15 | |
| 1913–14 | Southern League | 2 | 1 | 0 | 1 | 1 | 2 | 13 | |
| 1914–15 | Southern League | 1 | 0 | 0 | 1 | 0 | 2 | 20 | |
| 1919–20 | Southern League | 1 | 0 | 0 | 1 | 1 | 3 | 22 | |
| 1920–21 | Third Division | 42 | 8 | 12 | 22 | 34 | 74 | 22 | |
| 1921–22 | Third Division South | 43 | 14 | 8 | 21 | 48 | 63 | 18 | |
| 1922–23 | Third Division South | 42 | 15 | 7 | 20 | 51 | 59 | 16 | |
| 1923–24 | Third Division South | 44 | 12 | 14 | 18 | 43 | 60 | 15 | |
| 1924–25 | Third Division South | 42 | 13 | 14 | 15 | 35 | 44 | 13 | |
| 1925–26 | Third Division South | 44 | 18 | 8 | 18 | 59 | 50 | 10 | |
| 1926–27 | Third Division South | 46 | 12 | 12 | 22 | 57 | 74 | 20 | |
| 1927–28 | Third Division South | 45 | 15 | 11 | 19 | 67 | 88 | 16 | |
| 1928–29 | Third Division South | 44 | 10 | 10 | 24 | 44 | 88 | 22 | |
| 1929–30 | Third Division South | 43 | 11 | 8 | 24 | 51 | 82 | 21 | |
| 1930–31 | Third Division South | 44 | 15 | 10 | 19 | 69 | 81 | 16 | |
| 1931–32 | Third Division South | 43 | 10 | 8 | 25 | 41 | 87 | 21 | |
| 1932–33 | Third Division South | 46 | 19 | 10 | 17 | 79 | 68 | 7 | |
| 1933–34 | Third Division South | 44 | 12 | 11 | 21 | 80 | 98 | 17 | |
| 1934–35 | Third Division South | 43 | 11 | 13 | 19 | 55 | 77 | 20 | |
| 1935–36 | Third Division South | 44 | 15 | 9 | 20 | 71 | 79 | 16 | |
| 1936–37 | Third Division South | 44 | 19 | 8 | 17 | 57 | 69 | 11 | |
| 1937–38 | Third Division South | 43 | 10 | 6 | 27 | 39 | 81 | 22 | |
| 1946–47 | Southern League | 3 | 2 | 0 | 1 | 7 | 6 | 1 | |
| 1947–48 | Southern League | 5 | 2 | 2 | 1 | 7 | 5 | 2 | |
| 1949–50 | Southern League | 47 | 24 | 9 | 14 | 97 | 62 | 5 | |
| 1950–51 | Third Division South | 50 | 14 | 11 | 25 | 77 | 107 | 22 | |
| 1951–52 | Third Division South | 48 | 12 | 13 | 23 | 72 | 84 | 22 | |
| 1952–53 | Third Division South | 49 | 13 | 16 | 20 | 60 | 78 | 21 | |
| 1953–54 | Third Division South | 47 | 19 | 10 | 18 | 61 | 67 | 10 | |
| 1954–55 | Third Division South | 49 | 21 | 16 | 12 | 83 | 72 | 4 | |
| 1955–56 | Third Division South | 48 | 19 | 11 | 18 | 71 | 76 | 10 | |
| 1956–57 | Third Division South | 49 | 13 | 14 | 22 | 59 | 89 | 22 | |
| 1957–58 | Third Division South | 50 | 15 | 10 | 25 | 69 | 86 | 22 | |
| 1958–59 | Fourth Division | 48 | 20 | 10 | 18 | 85 | 83 | 11 | |
| 1959–60 | Fourth Division | 50 | 23 | 11 | 16 | 83 | 76 | 7 | |
| 1960–61 | Fourth Division | 51 | 17 | 14 | 20 | 72 | 79 | 15 | |
| 1961–62 | Fourth Division | 47 | 14 | 11 | 22 | 79 | 101 | 20 | |
| 1962–63 | Fourth Division | 50 | 24 | 13 | 13 | 78 | 55 | 5 | |
| 1963–64 | Fourth Division | 52 | 26 | 15 | 11 | 72 | 41 | 1 | |
| 1964–65 | Third Division | 50 | 24 | 10 | 16 | 73 | 55 | 7 | |
| 1965–66 | Third Division | 48 | 22 | 8 | 18 | 65 | 61 | 6 | |
| 1966–67 | Third Division | 53 | 17 | 19 | 17 | 67 | 73 | 11 | |
| 1967–68 | Third Division | 50 | 19 | 13 | 18 | 64 | 71 | 11 | |
| 1968–69 | Third Division | 51 | 14 | 17 | 20 | 60 | 73 | 20 | |
| 1969–70 | Third Division | 54 | 18 | 14 | 22 | 69 | 71 | 20 | |
| 1970–71 | Third Division | 48 | 10 | 13 | 25 | 43 | 70 | 24 | |
| 1971–72 | Fourth Division | 53 | 20 | 14 | 19 | 72 | 73 | 13 | |
| 1972–73 | Fourth Division | 49 | 20 | 11 | 18 | 65 | 62 | 9 | |
| 1973–74 | Fourth Division | 49 | 26 | 12 | 11 | 97 | 56 | 2 | |
| 1974–75 | Third Division | 50 | 17 | 16 | 17 | 68 | 65 | 10 | |
| 1975–76 | Third Division | 51 | 14 | 20 | 17 | 62 | 72 | 15 | |
| 1976–77 | Third Division | 50 | 17 | 13 | 20 | 59 | 68 | 12 | |
| 1977–78 | Third Division | 52 | 16 | 23 | 13 | 72 | 68 | 7 | |
| 1978–79 | Third Division | 50 | 21 | 18 | 11 | 68 | 49 | 4 | |
| 1979–80 | Third Division | 52 | 15 | 17 | 20 | 58 | 61 | 16 | |
| 1980–81 | Third Division | 54 | 15 | 21 | 18 | 55 | 64 | 15 | |
| 1981–82 | Third Division | 54 | 23 | 14 | 17 | 72 | 63 | 6 | |
| 1982–83 | Third Division | 54 | 19 | 14 | 21 | 69 | 70 | 13 | |
| 1983–84 | Third Division | 54 | 23 | 12 | 19 | 87 | 82 | 8 | |
| 1984–85 | Third Division | 54 | 30 | 8 | 16 | 99 | 74 | 4 | |
| 1985–86 | Third Division | 54 | 25 | 15 | 14 | 97 | 65 | 5 | |
| 1986–87 | Third Division | 58 | 28 | 11 | 19 | 83 | 69 | 5 | |
| 1987–88 | Third Division | 53 | 17 | 17 | 19 | 82 | 70 | 13 | |
| 1988–89 | Third Division | 52 | 14 | 5 | 33 | 56 | 93 | 23 | |
| 1989–90 | Fourth Division | 50 | 17 | 12 | 21 | 47 | 56 | 14 | |
| 1990–91 | Fourth Division | 49 | 13 | 18 | 18 | 59 | 64 | 15 | |
| 1991–92 | Fourth Division | 46 | 15 | 13 | 18 | 71 | 65 | 11 | |
| 1992–93 | Third Division | 51 | 13 | 16 | 22 | 60 | 75 | 21 | |
| 1993–94 | Third Division | 47 | 14 | 16 | 17 | 48 | 56 | 16 | |
| 1994–95 | Third Division | 47 | 11 | 12 | 24 | 50 | 72 | 19 | |
| 1995–96 | Third Division | 52 | 24 | 19 | 9 | 58 | 29 | 2 | |
| 1996–97 | Second Division | 56 | 25 | 12 | 19 | 71 | 65 | 11 | |
| 1997–98 | Second Division | 50 | 19 | 14 | 17 | 54 | 55 | 8 | |
| 1998–99 | Second Division | 52 | 23 | 16 | 13 | 79 | 51 | 4 | |
| 1999–00 | Second Division | 61 | 34 | 12 | 15 | 108 | 72 | 3 | |
| 2000–01 | First Division | 52 | 15 | 17 | 20 | 73 | 80 | 13 | |
| 2001–02 | First Division | 52 | 21 | 11 | 20 | 71 | 76 | 12 | |
| 2002–03 | First Division | 52 | 18 | 16 | 18 | 65 | 72 | 11 | |
| 2003–04 | First Division | 51 | 17 | 9 | 25 | 57 | 75 | 21 | |
| 2004–05 | Championship | 48 | 12 | 14 | 22 | 46 | 69 | 22 | |
| 2005–06 | League One | 50 | 18 | 12 | 20 | 56 | 71 | 14 | |
| 2006–07 | League One | 49 | 18 | 8 | 23 | 64 | 84 | 16 | |
| 2007–08 | League One | 51 | 13 | 14 | 24 | 54 | 82 | 22 | |
| 2008–09 | League Two | 55 | 25 | 14 | 16 | 65 | 61 | 5 | |
| 2009–10 | League One | 51 | 15 | 14 | 22 | 55 | 69 | 21 | |
| 2010–11 | League Two | 49 | 17 | 18 | 14 | 68 | 63 | 8 | |
| 2011–12 | League Two | 53 | 22 | 11 | 20 | 91 | 78 | 8 | |
| 2012–13 | League Two | 50 | 25 | 14 | 11 | 72 | 44 | 1 | |
| 2013–14 | League One | 50 | 15 | 9 | 26 | 62 | 86 | 17 | |
| 2014–15 | League One | 55 | 20 | 16 | 19 | 78 | 79 | 12 | |
| 2015–16 | League One | 51 | 21 | 13 | 17 | 76 | 64 | 9 | |
| 2016–17 | League One | 54 | 15 | 15 | 24 | 73 | 96 | 20 | |
| 2017–18 | League One | 54 | 17 | 18 | 19 | 65 | 70 | 17 | |
| 2018–19 | League One | 55 | 19 | 12 | 24 | 70 | 88 | 13 | |
| 2019–20 | League One | 43 | 15 | 17 | 11 | 53 | 46 | 10 | |
| 2020–21 | League One | 55 | 22 | 12 | 21 | 73 | 73 | 10 | |
| 2021–22 | League One | 53 | 9 | 19 | 25 | 40 | 78 | 21 | |
| 2022–23 | League Two | 58 | 18 | 18 | 22 | 49 | 63 | ||
| 2023–24 | League Two | 54 | 22 | 10 | 22 | 58 | 72 | ||
| 2024–25 | League Two | 51 | 14 | 17 | 20 | 45 | 57 | ||
| 2025–26 | League Two | 51 | 14 | 16 | 21 | 61 | 81 | Bradley Dack (7) | |
| 2026–27 | 3 | 0 | 1 | 2 | 0 | 6 |