Prior to Official Recognition
| Time | Team | Country | Venue | Date | Participants | Ref |
|---|---|---|---|---|---|---|
| 3:13.20 | United States |  | Eugene | 29 July 2016 | Kyle Clemons Claudia Francis James Harris Phyllis Francis | [1] |
The following table shows the world record progression in the mixed 4 x 400 metres relay . The first world record in the event was recognised by the International Association of Athletics Federations in 2019.
| Time | Team | Country | Venue | Date | Participants | Ref |
|---|---|---|---|---|---|---|
| 3:13.20 | United States | | Eugene | 29 July 2016 | Kyle Clemons Claudia Francis James Harris Phyllis Francis | [1] |
Awaiting ratification
| Time | Team | Country | Venue | Date | Participants | Ref |
|---|---|---|---|---|---|---|
| 3:12.42 | United States | | Doha | 28 September 2019 | Tyrell Richard Jessica Beard Jasmine Blocker Obi Igbokwe | [2] |
| 3:09.34 | United States | | Doha | 29 September 2019 | Wilbert London Allyson Felix Courtney Okolo Michael Cherry | [3] |
The 4 × 400 metres relay or long relay is an athletics track event in which teams consist of four runners who each complete 400 metres or one lap. It is traditionally the final event of a track meet. At top class events, the first 500 metres is run in lanes. Start lines are thus staggered over a greater distance than in an individual 400 metres race; the runners then typically move to the inside of the track. The slightly longer 4 × 440 yards relay was a formerly run British and American event, until metrication was completed in the 1970s.