The 4 × 400 metres relay at the World Championships in Athletics has been contested by both men and women since the inaugural edition in 1983.

The competition features three formats in relation to gender: men, women, and mixed.

The format utilizes one set of heats qualifying the top 8 into a final.

Note: * Indicates athletes who ran only in the preliminary round and also received medals.

Note: * Indicates athletes who ran only in the preliminary round and also received medals.