The trade unions Unite and the RMT balloted members working for the Wood Group on eight of Shell’s North Sea oil and gas platforms.
A total of 99.1 per cent of Unite members and 98.5 per cent of RMT members voted for strike action.
Dave Stewart, of the Wood Group, said the firm was “extremely disappointed” with the ballot result and would “continue to engage fully in discussions”.
The pending action follows the breakdown of talks at Acas the dispute resolution service, last week.
John Boland, Unite regional officer, said: “Despite the best efforts of the full-time officials and workforce shop stewards to broker a deal with the company, talks have failed to find an acceptable deal.
“We now find ourselves forced down the route of industrial action and in the coming days the workforce will determine the timing and nature of that action.
“That said, we remain available for talks should the company wish to consider an alternative offer. However, any talks must respect the workers and especially with regards to exercising their democratic rights in a dispute situation.”
Jake Molloy, RMT regional organiser, said the “battered and bruised” workforce had already gone through redundancies, an increased workload and the introduction of a rota that leaves them working three weeks on followed by three weeks off.
He said they were being told “to accept all of this with a reduction in salary of anything from 10 to 30 per cent”.
Mr Stewart, head of Wood Group’s eastern region, said: “We have met with the unions 11 times, and also with shop stewards and communication representatives. In addition, senior management have visited all those platforms involved to engage directly with the workforce.
“At no point did the terms and conditions proposed include a sweeping 30 per cent pay cut across those employees impacted.
“Around a third of those involved will experience no reduction to their base salary. The average reduction to base salary experienced by those employees involved in this consultation will be 3 per cent.”