Looking for a cheap flight? No problem, you might think. All you have to do is compare the prices of the budget airlines. Sadly, however, it’s not always that simple. Many low-cost carriers continue to quote a bargain initial price before bumping up the fare with an array of hidden charges that make it difficult to compare the final cost.

In February the Office of Fair Trading (OFT) gave the airlines three months to include all “fixed nonoptional costs” into the advertised price of their flights – a deadline which has now expired. While many budget airlines have bucked up their ideas, there is still significant room for improvement.

For example, a family of four travelling to Palma for a week before the school holidays with Ryanair would pay an initial price of £319.92. But the additional cost of tax, fees and charges (TFC) of £159.64 – almost half the cost again of the flight itself – brings the total cost to £479.56.

To discover what Ryanair’s extra charges actually are, you must click on the “details” of the TFCs, where the breakdown includes £40 in government tax, £45.60 for the nonrefundable “PSC” (passenger service charge) and £15.20 for “Ins & wchr levy”. Confused? Not surprising, as the latter refers to insurance and a wheelchair levy, which has to be paid by all passengers, whether or not they are disabled.

If you think that the charges you pay will be similar regardless of which airline you use, think again. The fares and charges vary significantly. For example, easyJet’s price for the same family travelling at the same time is £519.92, but only £88 of that relates to tax and no other charges are spelt out.

Samantha Day, of easyJet, says: “We only externalise two costs – air passenger duty and the passenger service charge – so when it says ‘tax and charges’ on our site, it is only those two. For many airlines it is a lot of smoke and mirrors; they bump up the tax and charges to make the lead fare look more attractive.”

However, Ms Day admits that easyJet has yet to change its website to comply entirely with the new OFT regulations, but that this would be completed “this summer”.

But there are things you can do to avoid paying more than you need to. For example, some airlines charge for each item of luggage checked in. Pay this online in advance and you can cut the baggage charges in half.

EasyJet allows you to have one bag weighing up to 20kg in the hold without charge, but extra baggage will cost £5 online or £10 at the airport. Clever packing can also save you cash. If the one bag you pack weighs more than 20kg, you will be forced to pay £6 for every kilogram over the 20kg threshold. But because smaller bags cost only £5 extra each it would often be cheaper to pack several lighter items of luggage.

Ryanair charges £5 for a 15kg bag online or £10 at the airport. If you go over this weight limit, you are charged £5.50 a kilo online or £10 a kilo at the airport. Bmibaby also charges for baggage checked into the hold. The online cost is £2.95 a bag for a one-way flight, compared with £6 at the airport. The limit is 20kg and you pay £5 a kilo, either online or at the airport, for anything above that.

However, very few people know how much luggage they are taking until they have packed, so booking this in advance may not be an option, although checking on the bathroom scales may help you to avoid excess baggage fees on top of the normal charges.

Paying by debit card instead of using your credit card will also cut costs. If you book with a credit card, Ryanair charges £2 each way for each passenger, while bmibaby has a fee of £4.95 per booking and easyJet charges 1.95 per cent of the payable amount, with a minimum of £4.95.

Paying by debit card is cheaper, but not always free. EasyJet charges £1 per person for a debit card transaction, although it is hard to see how else you would pay for an online flight if you did not want to incur the credit card fee. Ryanair charges 70p per person each way for a debit card transaction. But the advantage of paying by credit card is that you are covered under the Consumer Credit Act if something goes wrong.

Many airlines also add travel insurance to the cost of your flight. If you are not vigilant enough to uncheck the box, you can easily end up paying for cover that you may not want or need.

Often the best way to clinch the cheapest deal is to use price comparison websites such as travelsupermarket. com or skyscanner.net. These tot up all the fees and charges to give you a comparable price. Unfortunately, they are not yet able to compare baggage charges. Also, consumers can take some comfort from the OFT’s intention to “bring enforcement action” against airlines that are not including all obligatory fees in their pricing.

John Fingleton, the chief executive of the OFT, says: “The OFT is committed to ensuring that consumers are not misled by advertised prices that bear little relation to actual prices. We will enforce the law enthusiastically to ensure that consumer choice and competition are not distorted, and that both consumers and business have confidence in the market.”

How to cut costs

Booking well in advance will increase your chances of securing the lowest fares. Travelling midweek is often cheaper than flying on Saturdays or Sundays. Use a travel website such as skyscanner.net, cheapflights.co.uk or lastminute.com to save time searching for the best deals.

Check if the website automatically includes insurance. If you have your own travel cover, remember to uncheck the box to save more money. Check out The Times Holiday Handbook, available for £11.50 (free p&p) from The Times BooksFirst. Call 0870 1608080 or visit www.booksfirst.co.uk.

CASE STUDY: Bloated baggage fees

Kate Dobson, a frequent traveller, is an experienced flyer, but even she has been brought down to earth with a bump by the extra fees levied at the airport by the budget airlines.

Although they have “got much better” at displaying their charges, Miss Dobson, who works at Benenden School in Kent, has still found herself out of pocket. The 39-year-old says: “If you use them a lot, then you know that the advertised price is very different to what you will end up paying. But if you don’t use them often, then I think you would be surprised.

“I have had to pay £22.50 per item for luggage for going skiing when I booked online. But I flew back from Austria with slightly more luggage after buying a pair of boots and it cost me a further £15. I had already paid an extra £60.”

Miss Dobson says that budget carriers still offer good value if you can be flexible about when you travel and are often cheaper than rail fares if you are travelling in the UK.

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