Holidaymakers planning to leave their car at a UK airport this summer face a bewildering choice of options – and some crazy charges. However, you can bring down the cost by up to 30% simply by spending 10 minutes online before you go.

In the past, the airports closely controlled the cost of parking to the extent that it was rarely worth shopping around. But a host of websites – and even the airports’ own official parking websites – will cut the final price substantially, provided you pre-book.

This week, the Stansted airport official parking website quoted us £84 to leave our car for a week at its mid-stay car park – or £81 long stay. However, signing up to the official airport parking’s own email database would have given us a promotion code offering up to 25% off.

Instead, we opted for the Looking4.com website and, using the promotion code AWMSEPLUS, we were able to book the same week at the official mid stay car park for £66. This is still arguably an absurd price but much less that the £140 it would cost for our family of four to get the train to and from the airport.

For a two-week stay at Heathrow in July, the official airport site quoted us £79.40 to park in the official long-stay car park. Looking4.com quoted us £54, with a variety of parking firms.

If the parking firm is not an official one, it is certainly worth reading the reviews prior to booking. We would opt for a site where you park your car yourself, and we would avoid the cheapest companies that drive your car off-site as there have been too many horror stories to recommend using these.

The MoneySavingExpert.com site has a dedicated page listing four parking websites that it has negotiated deals with – and in some cases you need to book through its linked pages to get the discount.

This is one area where it pays to pre-book. If you just turn up and head into the car park, you will pay a significant price premium.