Aviation workers - predominantly low paid women - who are members of the GMB and Unite unions were set to walk out after a ten per cent pay cut imposed on them by BA during the pandemic was not reinstated.
Check-in crew and ground handling agents had been due to take part in the walkout, adding to fears BA would cancel yet more flights following months of travel disruption caused by a shortage of staff to cope with surging demand.
Workers will now receive an 8% consolidated pay rise, a one-off bonus and the reinstatement of shift pay, the union said.
Nadine Houghton, GMB National Officer, said: “No one wanted a summer strike at Heathrow, but our members had to fight for what was right.
“This improved pay deal came because of their efforts.
“Now these mainly women workers have won pay improvements for themselves – as well as forcing BA to make this offer to the rest of their staff too.
“Our members stood up for themselves and fought for what they were owed.
“These are frontline workers facing harassment and abuse from customers daily.
“The least they deserved is fair pay.”
Unite general secretary Sharon Graham said: “This is a great result for our check-in members at British Airways.
“By standing together, they have forced a corporate giant like BA to do the right thing and restore levels of pay slashed in the pandemic.”
Unite said the offer, which will be paid in several stages, is worth 13%.
The announcement will be welcomed by holidaymakers and other travellers who are facing serious disruption at airports, on roads and at ferry terminals as the great summer getaway gets into full swing.
Travellers have said waits at Dover are the worst they have experienced, with one lorry driver waiting more than 15 hours.
Muhammet Turker, a Turkish lorry driver, told the PA news agency he had been queuing in his HGV in Dover since 6pm on Thursday, and was still waiting to cross the Channel after 10am on Friday morning.
“I’ve been in something like this before, but this is the worst,” he said.
John Till, a railway manager from west Dorset, and his mother, Edna Johnson, 87, were due to travel to the Port of Dover on Friday but reports of the disruption prompted him to spend £400 changing his plans.
“I saw that people had already been queuing for four hours,” the 45-year-old told PA.
“I'm taking my elderly mother over to see some friends in (Bavaria in) Germany, so I have a really long drive on the other side when we arrive.
“I couldn't run the risk of being stuck in a queue for four hours with no toilets and the horrendous drive the other side, so at half four this morning I made the snap decision to rebook travel with Brittany Ferries and travel from the Port of Poole, which is a lot more expensive.”
The Port of Dover said in a statement: “On behalf of passengers trying to get on their way for a well-earned summer holiday, HGV drivers performing their critical role of delivering goods, our community who are severely impacted, our ferry operators awaiting their customers, our own port staff who have worked so hard in good faith and all of our Kent and Government partners with whom we have prepared together over several months for the busy summer:
“We are deeply frustrated that the resource at the French border overnight and early this morning has been woefully inadequate to meet our predicted demand and even more deeply regret the consequences that will now be felt by so many.”