The Women's 400 metre freestyle competition of the 2024 European Aquatics Championships was held on 23 June 2024.

[1][2] Prior to the competition, the existing world, European and championship records were as follows.

The heats were started at 09:30.Qualification Rules: The 8 fastest from the heats qualify to the final.

[3] The final was held at 19:14.

[4]