The market rate for exchanging £1 is €1.117 but the average airport rate in the UK for euros is 12% less, according to research by currency specialist FairFX.

However, some holidaymakers could receive 20% less euros for their pound, meaning they could lose over £100 worth of euros on a £500 exchange at the airport.

FairFX compared the exchange rates for euros at 17 UK airports and the amount of bang you’ll get for your buck varies considerably.

For instance, those heading to Stansted airport exchanging currency at Moneycorp will get a €0.89 euro rate, resulting in a 20.33% loss on the market rate or £101.64 on a £500 exchange.

But at the other end of the scale, those travelling from Heathrow airport (T1, 2, 3) who exchange their pounds at ICE will receive €1.11707, a 0.99% difference resulting in a loss of £4.95.

‘Extortionate differences’

Ian Strafford-Taylor, CEO of FairFX, said airport exchange rates are notoriously worse than the market rate.

“But some of the differences we’re seeing here are extortionate and families heading for Europe as the schools break up can end up paying a hefty price for the ‘convenience’ of getting their travel money at the airport. We’re seeing rates offered by airport providers reach shocking new lows with some of the highest margins we have seen since we began investigating exchange rates at airports.

“Travel money can often be left until the last minute and falls off the priority holiday checklist, especially when people are booking ‘last minute holidays’. But as we’ve found time and time again in our research, leaving it until you get to the airport could leave you out of pocket. This should be your very last resort.”

How to get top dollar for your pounds

Here are FairFX’s top tips to get the best value foreign currency for sterling:

• Follow the pound: If you’re not fixed on where you holiday, consider destinations where the pound is strongest which will help you explore more of the world, for less.
• Plan ahead: It’s never too soon to start thinking about your travel money. Follow your chosen rate so you can buy when the pound moves in your favour.
• Set up a tracker: If you don’t have time, ask an expert. FairFX has a free holiday money tracker which alerts you when rates improve which mean it could be the right time to buy your travel money.
• Lock-in your rate: Using a prepaid card means you can top-up the card when the rates are at their strongest and use it like a credit or debit card overseas – with the difference that your rate is often guaranteed in advance.
• Don’t leave it too late: Waiting until the last minute means you’ll have no choice about what rate you get. And if you leave it right up until you get to the airport, you’re likely to face the worst exchange rates in the country.

Related: See YourMoney.com’s Essential money-saving guide for your 2018 holiday for more ways to save.