| 1935-36 | Founder members of Eastern Counties League |
| 1936-37 | Joined Southern League |
|
| Southern League Champions |
| 1938-39 | Elected to Football League Division Three South |
| 1939-40 | Football League programme abandoned due to outbreak of war |
| 1953-54 | Football League Division Three South Champions |
|
| Promoted to Division Two |
| 1955 | Relegated to Division Three South |
| 1956-57 | Football League Division Three South Champions (on goal average) |
|
| Promoted to Division Two |
| 1960-61 | Football League Division Two Champions |
|
| Promoted to Division One |
| 1961-62 | Football League Champions |
| 1964 | Relegated to Division Two |
| 1967-68 | Football League Division Two Champions |
|
| Promoted to Division One |
| 1973-74 | UEFA Cup Quarter Finalists |
| 1974-75 | Missed runner-up spot on goal average |
|
| F.A. Cup semi-finalists |
| 1977-78 | F.A. Cup Winners |
| 1978-79 | European Cup Winners Cup Quarter Finalists |
| 1980-81 | Football League runner-up |
|
| UEFA Cup Winners |
|
| F.A. Cup semi-finalists |
| 1981-82 | Football League runner-up |
|
| Football League Cup semi-finalists |
| 1984-85 | Football League Cup semi-finalists |
| 1986 | Relegated to Division Two |
| 1986-87 | Missed promotion through play-offs (SF Ipswich Town 0 Charlton |
|
| Athletic 0, Charlton Athletic 2 Ipswich Town 1, Agg 1-2) |
| 1991-92 | Football League Division Two Champions |
|
| Promoted to Division One. Division One clubs then formed F.A. |
|
| Premiership |
| 1992-93 | Founder members of F.A. Premiership |
| 1995 | Relegated to Football League Division One |
| 1996-97 | Not promoted after play-offs (SF Sheffield United 1 Ipswich Town 1, |
|
| Ipswich Town 2 Sheffield United 2 - Agg 3-3, Ipswich Town lost on |
|
| away goals) |
| 1997-98 | Not promoted after play-offs (SF Ipswich Town 0 Charlton Athletic |
|
| 1, Charlton Athletic 1 Ipswich Town 0 - Agg 0-2) |
| 1998-99 | Not promoted after play-offs (SF Bolton Wanderers 1 Ipswich Town 0, |
|
| Ipswich Town 4 Bolton Wanderers 3, Agg 4-4, Ipswich Town lost on |
|
| away goals) |
| 1999-00 | Promoted to F.A. Premiership after play-offs (SF Bolton Wanderers |
|
| 2 Ipswich Town 2, Ipswich Town 5 Bolton Wanderers 3, Agg 7-5, F |
|
| Barnsley 2 Ipswich Town 4 @ Wembley) |
| 2000-01 | Football League Cup semi-finalists |
| 2002 | Relegated to Football League Division One |
| 2003-04 | Not promoted after play-offs (SF Ipswich Town 1 West Ham United 0, |
|
| West Ham United 2 Ipswich Town 0, Agg 1-2) |
| 2004-05 | Division One renamed "Football League Championship" |
|
| Not promoted after play-offs (SF West Ham United 2 Ipswich Town 2, |
|
| Ipswich Town 0 West Ham United 2 - Agg 2-4) |
