Portland Coastguard, police and ambulance swung into action about 3.15pm when a man was reported to be in difficulties about 500 metres off Wally's Ramp.

Because of the north to north-westerly winds of about 20 knots the man was being blown out to sea.

Portland Coastguard flotilla commander Stephen Brown said his service was dispatched to provide assistance, but a passing vessel was able to help just before the coastguard arrived.

"The person was unable get back into his kayak and we were dispatched," he said.

"A passing boat was able to help and the situation resolved enroute. He was treated and taken by ambulance to hospital and police were in attendance."

Mr Brown said it was a good result for everyone involved in the rescue.