Bureaux de change at UK airports have been accused of "profiteering" after handing travellers less than one euro to the pound.
The continued fall in sterling's value means that the average rate available at 16 airport bureaux de change is now just €0.99 to the pound, according to a survey by foreign exchange business FairFX.
The worst rate is currently ¢88 at Moneycorp at Southampton Airport and the best is €1.06 from the Change Group at Glasgow Prestwick.
Since the country's Brexit vote in June the pound has fallen by as much as 15% and has traded at 31-year lows.
But FairFX said some foreign exchange firms are charging as much as 26% commission for changing cash at the last minute, adding that this rate was "downright scandalous".
FairFX chief executive Ian Strafford-Taylor, said: "It's no secret that airport exchange rates aren't the best. They've got a captive audience and once you're there, you usually have no alternative. However, we're seeing rates offered by airport providers reach shocking new lows in what can only be described as downright scandalous."
Consumer champion Martin Lewis, of MoneySavingExpert.com in a tweet over the weekend, called Moneycorp's rate at Gatwick Airport of €0.9741 to the pound "disgraceful" and accused the firm of "profiteering".
Moneycorp retail director Tracy Bownes said: "The reason for our higher airport rates is the significant cost associated with operating there – from ground rent and additional security, to the cost of staffing the bureaux for customers on early and late flights. An easy and more cost-effective way for customers to buy travel money is to pre-order online and collect at the airport. We always encourage our customers to do this."
FairFX added that setting up alerts to buy when the rates are at their strongest and locking in rates by using a prepaid currency card, were also cheaper ways to buy foreign currency.