League Record as Swaythling
| Season | Position Finished | Played | Won | Drawn | Lost | For | Against | Points | League & Division |
| 1978/79 | 5th | 30 | 13 | 9 | 8 | 42 | 35 | 35 | Hampshire League Division 1 |
| 1979/80 | 9th | 30 | 11 | 5 | 14 | 39 | 41 | 27 | Hampshire League Division 1 |
League Record as Eastleigh
| Season | Position Finished | Played | Won | Drawn | Lost | For | Against | Points | League & Division |
| 1980/81 | 5th | 38 | 16 | 9 | 13 | 47 | 42 | 41 | Hampshire League Division 1 |
| 1981/82 | 4th | 38 | 19 | 8 | 11 | 63 | 29 | 46 | Hampshire League Division 1 |
| 1982/83 | 8th | 38 | 14 | 14 | 10 | 51 | 38 | 41 | Hampshire League Division 1 |
| 1983/84 | 4th | 38 | 16 | 14 | 8 | 51 | 33 | 46 | Hampshire League Division 1 |
| 1984/85 | 4th | 38 | 18 | 11 | 9 | 52 | 36 | 47 | Hampshire League Division 1 |
| 1985/86 | ▲5th | 38 | 20 | 9 | 9 | 69 | 45 | 49 | Hampshire League Division 1 |
| ▲Eastleigh left the Hampshire League to become a founder member of the Wessex League | |||||||||
| 1986/87 | 8th | 32 | 14 | 6 | 12 | 40 | 42 | 48 | Wessex League |
| 1987/88 | 12th | 36 | 13 | 8 | 15 | 36 | 39 | 47 | Wessex League |
| 1988/89 | 9th | 32 | 10 | 10 | 12 | 39 | 34 | 40 | Wessex League |
| 1989/90 | 14th | 36 | 10 | 11 | 15 | 60 | 66 | 41 | Wessex League |
| 1990/91 | 12th | 38 | 13 | 8 | 17 | 40 | 62 | 47 | Wessex League |
| 1991/92 | 10th | 36 | 18 | 4 | 14 | 61 | 53 | 58 | Wessex League |
| 1992/93 | 9th | 40 | 17 | 9 | 14 | 68 | 54 | 60 | Wessex League |
| 1993/94 | 15th | 42 | 12 | 12 | 18 | 47 | 54 | 48 | Wessex League |
| 1994/95 | 14th | 42 | 14 | 9 | 19 | 66 | 73 | 51 | Wessex League |
| 1995/96 | 4th | 40 | 21 | 13 | 6 | 83 | 50 | 76 | Wessex League |
| 1996/97 | 7th | 40 | 19 | 8 | 13 | 71 | 56 | 65 | Wessex League |
| 1997/98 | 4th | 38 | 20 | 11 | 7 | 74 | 31 | 71 | Wessex League |
| 1998/99 | 4th | 38 | 22 | 8 | 8 | 69 | 43 | 74 | Wessex League |
| 1999/00 | 7th | 40 | 20 | 8 | 12 | 67 | 46 | 68 | Wessex League |
| 2000/01 | 7th | 44 | 23 | 10 | 11 | 87 | 48 | 79 | Wessex League |
| 2001/02 | 13th | 44 | 18 | 9 | 17 | 91 | 71 | 63 | Wessex League |
| 2002/03 | ▲1st | 42 | 32 | 7 | 3 | 115 | 32 | 103 | Wessex League |
| 2003/04 | ▲4th | 42 | 27 | 4 | 11 | 88 | 40 | 82* | Southern League Division 1 East |
| ▲Due to the formation of the Football Conference North & South Divisions, Eastleigh were placed in the Isthmian League | |||||||||
| 2004/05 | ♦▲3rd | 42 | 22 | 13 | 7 | 84 | 49 | 79 | Isthmian League Premier Division |
| 2005/06 | 8th | 42 | 21 | 3 | 18 | 65 | 58 | 66 | Football Conference South |
| 2006/07 | 15th | 42 | 11 | 15 | 16 | 48 | 53 | 48 | Football Conference South |
| 2007/08 | 6th | 42 | 19 | 10 | 13 | 76 | 62 | 67 | Football Conference South |
| 2008/09 | ♦►3rd | 42 | 25 | 8 | 9 | 69 | 49 | 83 | Football Conference South |
| 2009/10 | 11th | 42 | 17 | 9 | 16 | 71 | 66 | 60 | Football Conference South |
| 2010/11 | 8th | 42 | 22 | 6 | 14 | 74 | 53 | 72 | Football Conference South |
| 2011/12 | 12th | 42 | 15 | 9 | 18 | 57 | 63 | 54 | Football Conference South |
| 2012/13 | ♦►4th | 42 | 22 | 6 | 14 | 79 | 61 | 72 | Football Conference South |
| 2013/14 | ▲1st | 42 | 26 | 8 | 8 | 71 | 40 | 86 | Football Conference South |
| 2014/15 | ♦►4th | 46 | 24 | 10 | 12 | 87 | 61 | 82 | Football Conference Premier |
| The Football Conference was renamed and became the National League | |||||||||
| 2015/16 | 7th | 46 | 21 | 12 | 13 | 64 | 53 | 75 | National League |
| 2016/17 | 15th | 46 | 14 | 15 | 17 | 56 | 63 | 57 | National League |
| 2017/18 | 14th | 46 | 13 | 17 | 16 | 65 | 72 | 56 | National League |
| 2018/19 | ♦►7th | 46 | 22 | 8 | 16 | 62 | 63 | 74 | National League |
| 2019/20 | 16th | 37 | 11 | 13 | 13 | 43 | 55 | 46 | National League |
| 2020/21 | 9th | 42 | 18 | 12 | 12 | 49 | 40 | 66 | National League |
| 2021/22 | 19th | 44 | 12 | 10 | 22 | 52 | 74 | 46 | National League |
| 2022/23 | 9th | 46 | 19 | 10 | 17 | 56 | 57 | 67 | National League |
| 2023/24 | 13th | 46 | 16 | 11 | 19 | 73 | 87 | 59 | National League |
| 2024/25 | 13th | 46 | 14 | 17 | 15 | 58 | 61 | 59 | National League |
| 2025/26 | - | - | - | - | - | - | - | - | National League |
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Footnotes |
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| * | 2003/04 - Deducted 3 points |