Missing NSW man's body found in river

The body of a missing 18-year-old who went for a swim in the Hawkesbury River during a party on a house boat has been found.

Westpac Life Saver helicopter confirmed the body was recovered on Saturday morning after the teenager was reported missing on Friday night.

He had been enjoying a party with family and colleagues on the house boat before jumping in to the river for a swim, police said.

Worried family members alerted the emergency services when he failed to return around 8.30pm.

A search involving police helicopters and NSW Marine Rescue was launched, with specialist police divers joining the hunt at first light on Saturday.