Portugal competed at the 2015 World Aquatics Championships in Kazan, Russia from 24 July to 9 August 2015.

Portugal fielded a full team of three swimmers to compete in the open water marathon.

[1] Portuguese swimmers have achieved qualifying standards in the following events (up to a maximum of 2 swimmers in each event at the A-standard entry time, and 1 at the B-standard):[2][3][4]