Unite said it will ballot its members over claims that Prestwick airport’s management has refused to pay shift pay and meet the Real Living Wage rate (£9.90) for the lowest paid and new starters.
The union said members are also angry about having to take a pay cut amid record inflation.
It said with the Retail Prices Index (RPI) standing at 11.7 per cent, the offer on the table for the workforce of between 4% and 6.5% is “a significant real terms pay cut”.
Leading Unite members, who said they use RPI as the real inflation figure rather than Consumer Price Inflation (CPI), said the offer is “completely unacceptable”.
The ballot, which opened on Tuesday and closes on July 19, will include airport security, firefighters, airfield operators, ground crew, ground handling, cargo, customer services, and cleaners.
Unite general secretary Sharon Graham said: “Prestwick Airport and the Scottish Government need to urgently improve their pay proposals for these workers.
“While directors’ pay is protected, workers are being told to take a substantial real terms pay cut.
“And disgracefully, they want to keep new starters on a rock bottom rate that is lower than the real living wage.
“Prestwick Airport and the Scottish Government need to put an improved offer on the table because Unite will resolutely support our members in their fight for better jobs, pay and conditions.”
The airport was taken into public ownership in November 2013 after it was bought by the Scottish Government for £1.
Unite said Government officials need to “practise what they preach” after a Fair Work plan was introduced for Scotland to promote fair working practices.
Siobhan McCready, Unite industrial officer, said: “Prestwick Airport is proposing to pay less than the Real Living Wage for some of our members, which makes a mockery of the Scottish Government’s Fair Work agenda.
“Both the Airport and the Scottish Government should be setting a lead and practising what they preach. It’s double standards of the highest order.
“The offer on the table is completely unacceptable and our members are not prepared to tolerate lousy pay. Simply put, they have had enough.”