British Airways says all scheduled flights have left Heathrow as planned on Monday, with only 200 passengers still waiting for flights.
Hundreds of passengers are waiting for their flights
"We're returning to normal," said BA spokesman Tony Crane.
Talks between union leaders and the caterer at the heart of the dispute failed to find agreement on Monday, but will resume again on Tuesday morning.
The Transport and General Workers' Union wants the reinstatement of 670 sacked Gate Gourmet staff.
Their dismissal led to a sympathy strike by BA baggage handlers which disrupted many BA flights from Thursday to Sunday, bringing chaos to 70,000 Heathrow passengers.
T&G general secretary Tony Woodley dismissed the catering firm's offer to reinstate half the sacked staff, saying it was "not acceptable".
"If you want to cut costs there's no quicker way to do it, really, is there, than to sack decent hard-working men and women for no justifiable reason other than you want to bring in cheaper labour on the cheap," he claimed.
Gate Gourmet has maintained that it has to change "outdated working practices" and cut costs at its UK operations in the face of huge losses.
Weekend talks between Gate Gourmet and the T&G failed to find a solution to the original dispute.
The BBC's industrial correspondent Stephen Cape said the catering firm does not want to re-employ all the sacked staff as it believes some are "troublemakers who would obstruct change".
Mr Woodley has met "top people" from BA after calling for the airline's help to end the dispute, according to a union spokesman.
"The stakes remain very high," the spokesman added.
Gate Gourmet has denied a report that the sackings followed a blueprint drawn up months beforehand.
According to a report in the Daily Mirror, a team from the firm's US owners Texas Pacific Group drew up a plan to provoke workers into striking so that they could be dismissed and cost savings made.
Gate Gourmet has denied the strike was deliberately provoked.
"The document was fielded as a proposal by former management... current management discarded the plan and its recommendations as entirely inappropriate and undesirable," a Gate Gourmet spokesman said.
A spokesman for Gate Gourmet said it was currently providing a basic catering service on all BA flights.
Some 200 people still stranded by the strike were still waiting at hotels near Heathrow on Monday night, but BA said all 200 passengers now had confirmed bookings on flights scheduled to depart by Thursday.
The cost of the strikes to BA in loss of revenues, refunds and the expense of accommodating passengers in hotels is estimated at up to £40m by airline industry analysts.
A spokesman said: "Everybody who was on a cancelled flight now has a reconfirmed ticket."
But some delayed travellers said they were angry they had not been given priority over customers with seats for current travel.
Heba Osman, waiting since Thursday with her family of six for a flight to Egypt, said: "They should be organised for things happening like this, so that people like us, the small people, don't have to suffer."
Baggage handlers are also working to return pieces of luggage which have become "stuck in the system" to their owners.
About 5,000 bags were due to be forwarded on Monday.