The flight ban is said to have cost London £100m
UK airlines are continuing in their efforts to bring back passengers stranded after volcanic ash disruption.
British Airways (BA) said it was continuing to put on extra flights and that its operation was ongoing.
Virgin said it hoped to have all passengers back from areas such as the Caribbean by the end of the week.
Both airlines said their schemes asking people already booked on long haul flights to give up their seats to stranded passengers were going well.
British airspace reopened on Tuesday following almost a week of grounded flights.
A BA spokesperson said: "This is a fast moving situation, and we need to make sure get them home as quickly as we can."
She said the operation to repatriate passengers would continue on a "rolling basis".
Easyjet said it was setting up stand-by desks in airports to process waiting passengers, while Ryanair said it had cleared its backlog.
Travel journalist Simon Calder said holiday firm Thomson aimed to bring all its stranded customers back by Monday.
Emirates said it was putting on extra flights, and that it had repatriated 6,000 passengers so far. The airline said the vast majority would be back home in the next week or so.
American Airlines said it was "very close to finishing the repatriation".
Teacher Marc Davis said he spent an extra £1,000 as he battled to get home to Devon from Kuala Lumpur in Malaysia.
He said he had to pay for an unexpected hotel stay and then had to sleep overnight at the airport to secure a place on one of the few extra flights out.
"As well as the expense in Malaysia, I had to pay for the extra days my car was parked at Heathrow Airport, the additional time my dog was in the kennel and essential calls on my mobile phone," he said.
Meanwhile, the closure of UK airspace is estimated to have cost London more than £100m in lost tourist spending.
According to London's mayor and Visit London, hotel occupancy was down as much as 25%, and theatre, restaurants and shops have all seen a fall in visitors.
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