Which? Travel has targeted the car hire sector in its latest investigation, claiming hidden fuel charges are bumping up the cost of overseas car rental by up to three times.
It sent undercover researchers to Spain to investigate car hire companies after receiving complaints from Which? members about being hit by large charges for fuel that were not made clear at the time of booking.
According to the consumer magazine, a researcher in Malaga was told the cheapest initial car-hire price including basic insurance was from Goldcar at €30.25. But when fuel was added on arrival, the price rose to €94.25.
In Alicante the researcher rented from UK broker Holiday Autos, locally-based company Centauro and direct from Hertz.
"At the time of the booking, Holiday Autos was the cheapest at €28, compared to €52.70 for Centauro and €65.58 for Hertz. However, once we picked up the car and fuel was added on, the Holiday Autos price rose to a huge €144.77 including enhanced insurance and fuel," said Which?.
"Companies used a ‘full-empty’ policy, in which consumers are charged for a full tank of petrol when they pick up the car and given no refunds for any fuel they do not use. The impact of these charges on the total price is not made clear when customers made the booking."
Which? Travel expert Rochelle Turner said: "All charges should be shown up-front at the time the booking is made so consumers can make the right choice and compare prices easily."
