Members of the 17th Dáil Changes Changes

| Date_ | Constituency | Gain | Loss | Note_ |
|---|---|---|---|---|
| 19 February 1964 | Cork Borough | Fianna Fáil | Fianna Fáil | Sheila Galvin (FF) wins the seat vacated by the death of her husband John Galvin (FF) |
| 19 February 1964 | Kildare | Fianna Fáil | Labour Party | Terence Boylan (FF) wins the seat vacated by the death of William Norton (Lab) |
| 8 July 1964 | Roscommon | Fine Gael | Fine Gael | Joan Burke (FG) holds the seat vacated by the death of her husband James Burke (FG) |
| 3 December 1964 | Galway East | Fine Gael | Clann na Talmhan | John Donnellan (FG) wins the seat vacated by the death of his father Michael Donnellan (CnaT) |
| 10 March 1965 | Cork Mid | Labour Party | Labour Party | Eileen Desmond (Lab) holds the seat vacated by the death of her husband Dan Desmond (Lab) |