Agents are urging operators to delay balance payments to four weeks before departure to give clients more time to decide if they still wish to travel.
Balance due dates are now coming up for departures in June. Most balances are due at least ten weeks ahead of travel.
Miles Morgan Travel owner Miles Morgan said delaying requests for balances would alleviate the issue.
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He said: “If a client has a holiday booked and they have committed £60 and the operator wants the £5,000 balance, it’s a really difficult decision to make.
“By changing the balance due date it offers the clients more thinking time rather than them having to pay it now and then finding at a later date they can only get their money back in vouchers.”
He called on trade bodies such as Abta to take the lead on the issue.
He said: “No-one expected this situation but it doesn’t mean there cannot be a level of coordination to address it. We cannot talk to suppliers about this, they are fighting fires. Everyone has their back to the wall. We are looking for leadership from the bodies that run our industry.”
Suffolk-based Deben Travel owner Lee Hunt said some customers were refusing to pay full balances due to the ongoing uncertainty.
He said: “Customers are starting to lose trust and now we’re having problems with customers who do not want to pay full balances.
“Today we had a couple cancel an Inghams booking. The balance payment was due yesterday and they didn’t want to pay because of the uncertainty.
“If operators could be flexible with due dates and take it down to the absolute minimum that would not only help but it would save bookings.”