Patong police sent the body of Stephan Henricus Maria Buczynski, 26, to Bangkok to confirm the finding of a local doctor at Patong Hospital.
Mr Buczynski carried a large sum of money in a watertight bag around his neck and had a four-centimetre cut on the back of his head.
He was one of four expat men to die in Patong on January 13. A total of 10 expats died in Patong in the 10 days between January 11 and January 20.
Mr Buczynski parents, already on Phuket, are expected to accompany their son's body home.
Two Australians involved in an unrelated argument with Mr Buczynski and a friend days before the drowning have already flown home.