Manufacturing union MSF has won recognition at Bristow Helicopters after beating off a challenge from engineering union AEEU.
In a secret ballot, just over seven out of 10 employees at the company voted in favour of recognition.
The agreement will cover nearly 1,000 staff at 10 sites, including the company’s Aberdeen headquarters.
The deal covers wages, working hours, holiday entitlement, pensions, training and union representation.
A spokesman for MSF said the company had been opposed to union recognition under its previous owners, but had since changed its stance.
He added that MSF had a number of members at the plant which helped it win the vote ahead of the AEEU. Compulsory union recognition laws, passed by Parliament in July, are set to come into force in Spring 2000.
Delays in introducing the regulations are thought to be an attempt by the Government to encourage such voluntary deals.