This is the progression of world record improvements of the 400 metres W45 division of Masters athletics.
| Hand | Auto | Athlete | Nationality | Birthdate | Location | Date | |
|---|---|---|---|---|---|---|---|
| 56.14 | Angee Henry-Nott | 21 December 1975 | Ames | 23 July 2021 | |||
| 56.15 | Marie Lande Mathieu | 26 November 1956 | Carolina | 12 July 2003 | |||
| 56.82 | Mary Libal | 28 June 1950 | Buffalo | 22 July 1995 | |||
| 57.8 | Jan Hynes | 3 April 1944 | Brisbane | 1 March 1989 | |||
| 59.68 | Colleen Mills | 23 November 1933 | Christchurch | 10 January 1981 |