Almost 1,000 workers at Gatwick Airport, including baggage handlers and check-in staff, are to strike in a dispute over pay.
Members of Unite employed by four private contractors will walk out for four days from July 28th and again for four days from August 4th.
The union said the action will “inevitably” cause disruption to flights at the height of the summer holiday season.
Those involved in the dispute are employed by ASC, Menzies Aviation, GGS and DHL Services, which conduct outsourced operations for airlines including ground handling, baggage handling, ramp agent, dispatchers, and check-in.
Unite said it has been in negotiations with the four companies since January but claimed they have failed to make offers that meets the workers’ expectations.
The union’s general secretary Sharon Graham said: “Our members at Gatwick Airport undertake incredibly demanding roles and are essential to keeping the airport and airlines working, yet their employers somehow think it is acceptable to pay them a pittance.
“As part of Unite’s unyielding focus on the jobs, pay and condition of its members, the union has drawn a line in the sand and is committed to eradicating the scourge of low pay at the airport.”
A total of 4,410 flights are scheduled to depart Gatwick across all the strike days, equating to more than 840,000 seats, aviation data company Cirium said.
The airport is already suffering major disruption due to air traffic control (ATC) restrictions.
Strikes, staff shortages and air space closures related to the war in Ukraine mean ATC providers are limiting flight numbers across Europe.
Gatwick is the busiest single-runway airport in the world, but its flight numbers are currently capped at peak times due to the ATC issue.
The problem recently forced easyJet to cancel 1,700 summer flights, mostly from Gatwick.
A Gatwick spokesperson said: “We are aware of the recent ballot result and will support our airlines with their contingency plans to ensure that flights operate as scheduled.”