Heathrow has insisted no flights will be cancelled due to the next strike by security staff coinciding with the start of the late May school half term.
The London hub urged the Unite union to accept a 10% pay rise and condemned the industrial action on May 25-27 as “completely unnecessary”.
Chief executive John Holland-Kaye said: “Passengers should not be concerned about strike action by Unite over the half term getaway.
“The 15 days of strike action over the Easter peak and coronation weekends have had no impact on the smooth running of the airport, and passengers have not noticed any difference from the normal great service they expect at Heathrow.
“These strikes are completely unnecessary. When I speak to colleagues the overwhelming message is that they just want to vote on our pay offer, but Unite won’t let them.
“We made a generous 10% offer early on, to make sure colleagues got a substantial increase when they needed it most.
“Unite’s delays mean non-union colleagues as well as the majority of colleagues who are union members, who voted to accept our previous offer are losing out.”
The 10% pay increase has been on the table since January and has subsequently been improved with a £1,150 lump sum and a guarantee of an inflation-linked increase in 2024.
However, Unite countered that its research has revealed that the average pay for Heathrow workers has fallen in real terms by 24% since 2017 and that security officers are paid less than workers at other major airports in London and the south east.
Unite regional co-ordinating officer Wayne King said: “There is absolutely no justification for security officers at Heathrow being paid far less than comparable officers at other London airports.
“Heathrow regularly trumpets how successful it is as the UK’s premium airport so there is no defence in it paying bargain basement wages. Heathrow can clearly meet a cost of living increase for our members; they’re deliberately choosing not to, pushing our members deeper into financial difficulties.”