More than 3,000 workers at Stanlow, Fawley, Valero, Grangemouth and Mossmorran Oil Refineries, as well as at Sellafield Nuclear Facility had voted in favour of industrial action.
But they accepted a pay deal today worth more than 17 per cent over two years.
The workers, who are covered by the National Agreement for the Engineering Construction Industry (NAECI), will now earn an extra 11.3 per cent for 2024 and an additional 5.5 per cent for 2025, along with improvements to sick pay and other allowances.
Charlotte Brumpton-Childs, GMB National Officer, said: “These skilled workers have fought for the pay rise they so richly deserve.
“After watching their pay erode due to rampant inflation, they stood together and forced this whopping deal.
“They should be rightly proud of themselves.”
Unite national officer Jason Poulter said:“This excellent result is a prime example of the benefits to be gained by being part of Unite. Unite will continue to build on our industrial strength in the construction sector so we can continue winning for workers.”