Travel websites were accused last week of misleading the public by advertising low package-holiday prices that did not include compulsory hidden extras.

The Trading Standards Institute, which published the report, said “budget holiday companies” were to blame. The Association of British Travel Agents (Abta) agreed, adding that some “no-frills” companies had refused to sign up to its code of practice calling for inclusive pricing.

However, a survey last week by the Travel section revealed that the use of hidden must-have supplements is widespread, with all of Britain’s “big four” tour operators guilty.

At Thomson.co.uk, we found a week’s self-catering in Mallorca reduced from £140 to £54. But the final cost, with occupancy and fuel supplements included, was £93.

Thomascook.com had a week’s B&B in Agadir “from £144”. Even by opting out of resort transfers, in-flight meals and an increased luggage allowance, we only managed to get the price down to £196.

Firstchoice.co.uk advertised a week’s skiing in Andorra “from £142”, based on four adults sharing a room. However, the real price was £223, including some extras not even explained on the website.

MyTravel.com showed greater transparency at the booking stage, but still advertised prices that did not exist. It claimed it had a week in the Algarve, departing on December 10, from £84 but, once we clicked through, the first available departure was on December 17, priced £251.

Not all companies use the same tactics. Trailfinders has a policy of “no hidden extras”, and does not use 0870 numbers or levy credit-card fees. Last week, its chairman, Mike Gooley, called for more transparency in the industry.

The Trading Standards Institute wants the Office of Fair Trading to use existing legislation to crack down on misleading pricing. It also accused tour operators of including hefty fuel surcharges in 2007 brochures, even though prices have stabilised.

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