Qualified 8th from heats. Finished 7th at 2021 World Relays. Placed 15th at 2019 European Games. Ireland qualified for 2020 OG through their performance at the 2021 World Relays, where they progressed from their heat courtesy of the fourth-fastest time. That time would have won them a medal in the final, but they ran just under three-and-a-half seconds slower in the final.
Qualified 5th from heats. Finished 4th at 2019 WCh. Placed 5th at 2021 World Relays, 12th in 2019. GBR narrowly missed out on a medal when the event made its first appearance at the world championships in 2019. They finished in fourth place, 0.45s behind bronze medallists Bahrain. GBR did not qualify for the final at the 2019 World Relays in Yokohama, but finished fifth in the 2021 final.
Qualified 9th from heats by jury of appeal. Finished 14th at 2019 WCh. Placed 13th at 2021 World Relays, 7th in 2019. Finished 8th at 2018 European Games. Placed 8th at 2017 Youth WCh, 4th in 2015. Germany qualified for the 4x400m mixed relay via the world rankings, at an event on home soil in Regensburg, Germany, in June 2021. Failed to make the final at the 2021 World Relays.
Qualified 3rd from heats. Gold at 2019 WCh. Gold at 2019 World Relays, silver in 2017. Gold at 2015 Youth WCh. USA won gold in a world-record time when the event first appeared at 2019 WCh in Doha, Qatar, beating Jamaica by 2.44 secs. USA also won at the 2019 World Relays in Yokohama, Japan, beating Canada by 1.72 seconds. At the 2017 World Relays, USA took silver behind the Bahamas.
Qualified 1st from heats. Finished 5th at 2019 WCh. Placed 10th at 2021 World Relays, 5th in 2019, 4th in 2017. Placed 23rd at 2019 European Games. Finished 5th at 2015 Youth WCh. At 2019 WCh in Doha, Qatar, Poland finished 0.05s behind Great Britain in fourth place. Have contested all three World Relays to feature the event.
Qualified 6th from heats. Bronze at 2021 World Relays. DSQ at 2015 Youth WCh. The Dominican Republic mixed 4x400m relay team qualified for Tokyo by making the final at the 2021 World Relays in Poland. They qualified third-fastest in the heats, and repeated the performance in the final to claim bronze. They finished 0.04s behind runners-up Brazil, and just under a second behind winners Italy.
Qualified 2nd from heats. Finished 8th at 2021 World Relays Championship, their first competitive appearance in this event. NED qualified for Tokyo through their performance at the 2021 World Relays in Poland. Despite running the ninth-fastest time in the heats overall, they qualified for the final having finished first in their heat, with the top two places automatically progressing.
Qualified 7th from heats. Finished 6th at 2019 WCh. Placed 4th at 2021 World Relays, 8th in 2019. Belgium placed sixth when the event was first contested at WCh in 2019 in Doha, Qatar. They finished last in the final of the first edition of the World Relays in 2019. BEL improved to fourth place in the final at the 2021 World Relays, 0.34s behind bronze medallists the Dominican Republic.
Qualified 4th from heats. Silver at 2019 WCh. Bronze at 2017 World Relays, 9th in 2019. Silver at 2017 Youth WCh, 10th in 2015. Beat bronze medallists Bahrain by just 0.04s at 2019 WCh in Doha, Qatar, but finished nearly two-and-a-half seconds behind USA. At the 2019 World Relays in Yokohama, the Jamaican team missed out on qualifying for the final by 0.21s behind Brazil.
USA
POL
IRL
GBR
GER
DOM
NED
BEL
JAM
