An inquest at Oxford Coroner's Court heard that Baltazar Da Costa, 14, drowned after going to the aid of two friends in a tributary of the River Thames. The incident occurred near Donnington Bridge in Oxford on 27 May.
Baltazar, who could not swim, was with a group of friends playing with a ball when it landed in deeper water. Two girls who tried to retrieve it got into difficulty, and when Baltazar went to help, he slipped beneath the river.
Thames Valley Police were called to the scene at about 17:30 BST. Baltazar was found under the water shortly after 18:00 and was pronounced dead at the scene despite paramedics working for over an hour to resuscitate him. Coroner Darren Salter recorded a finding of accidental death.