RYANAIR has been 'ripping off' customers with 'misleading' currency conversions.

Research conducted by Which? found the budget airline is continuing to automatically switch currencies at the time of payment, meaning UK flyers are unknowingly paying more.

Researchers said that, in one instance, a family of four faced being charged an extra £30 by paying for their flight using Ryanair’s “dynamic currency conversion”.

Which? called this finding “shocking,” adding that passengers would be better off sticking to payment in euros and letting their card provider do the currency exchange instead.

This bumped up rate been going unnoticed by many flyers as the change is automatic.

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Which? is now calling on the aviation regulator to take action to clamp down on the practice.

Caroline Normand, Which? director of advocacy said: “This cynical and misleading pricing trick is one of the clearest examples of a rip-off we have seen – but Ryanair has been allowed to get away with it due to a lack of action from the Civil Aviation Authority.

“If the regulator is committed to helping improve the experience of passengers, it must clamp down on this practice before thousands more holidaymakers are caught out this summer.”

This week’s findings are set to infuriate passengers after the airline faced criticism for changing its hand luggage policy twice last year, resulting in charges for passengers flying with small wheelie suitcases.

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Ryanair was named the worst airline serving UK airports for the sixth year in a row at the start of the year by Which?

Defending its currency conversion rates, a Ryanair spokeswoman told the Evening Times: “Ryanair’s currency conversion presentation is fully transparent and complies with all applicable EU and national laws on consumer protection.

“Customers have the option of paying in the currency of their payment card which gives absolute certainty of the final payment amount.”