Workers on an Auckland vehicle and freight ferry have voted to strike from next week because of pay disparity.
SeaLink operates ferries carrying vehicles, passengers and freight between Auckland, Waiheke Island and Great Barrier Island.
First Union organiser Justin Wallace said about 50 workers would stage rolling strikes from 24 September until 1 October.
"There's a big wage disparity growing on the harbour, and SeaLink First Union members are looking for parity," he said.
Workers wanted wages and conditions to match those employed by Auckland Transport ferry providers, who had been helped by a cash injection to increase pay for crew.
"SeaLink's workers are struggling with the absurd cost of living in Auckland while going to work every day knowing that they are being underpaid compared to colleagues who do the same work as them on a different ferry provider," Wallace said.
Members did not want to let customers down, but they now saw strike action as the only option, he said.
SeaLink ferries has been approached for comment.