Uncovered: the skiers who end up skating on thin ice

One of the warmest winters on record - a telling effect of climate change - has meant little or no snowfall for some of Europe's top ski resorts, and left frustrated skiers and snowboarders desperately seeking fresh powder.

But after a slow start to the season, fresh snow is now falling in some areas, and this will prompt many of us to dig out our sunglasses and salopettes, and head for the slopes before the season ends in April.

Thanks to low-cost airlines and great exchange rates, more of us are opting for newer and cheaper destinations such as Bulgaria and Slovenia - although France and Switzerland remain firm favourites.

But wherever you choose to ski or snowboard, the golden rule is always the same: buy insurance. While a few tumbles are par for the course, you could end up out of pocket in the event of a serious injury - unless you have adequate cover.

It's a warning many of us ignore. According to the financial comparison service Moneysupermarket.com, every fourth skier or snowboarder is underinsured for injury to themselves or others. This makes little sense when common problems such as torn ligaments, sprains and breaks could set you back several thousand pounds in medical bills. And the costs can soar into tens of thousands if you need to be flown home in the event of a serious accident.

Ambulance transport to a hospital in Europe, the US and Canada could cost from £300 to £500, says the Post Office, while evacuation from the slopes via helicopter will lead to a bill of between £1,000 and £2,000.

Repatriation could set you back up to £4,000 in Europe, rising to £8,000 in the US and Canada, and medical bills are also much higher in the States.

The first step for anyone travelling to a resort in the EU is to get hold of a European Health Insurance Card (EHIC) - the replacement for the E11 form. This entitles you to free - or cut-price - basic medical treatment on the same terms as the nationals in all EU states.

However, the EHIC won't cover you for costly extras such as an air ambulance, personal liability, trip cancellation or loss of baggage - so it should not be viewed as a substitute for insurance.

Neither should you assume a standard travel policy is enough; you will usually need to buy winter sports cover as an add-on.

Moneysupermarket recommends skiers take out a policy offering at least £2m in medical expenses, £1m for personal liability, £3,000 cancellation, £1,500 baggage and £250 cash.

Check the small print, though, as ski insurance can be riddled with exclusions. For example, many policies won't provide cover you if you fancy trying your hand at other winter sports - such as bobsleighing, luge, toboganning, snow-mobiling and even ice-skating.

"Contents vary between providers," says Robin Amlot from comparison service Moneyextra. "Norwich Union covers seven sporting activities including off-piste skiing and snowboarding, while AIG also covers certain 'extreme' sports such as heli-skiing."

If your preferred activity isn't specified, find out if you can add it to the policy.

Speak to a number of insurers before you buy, as the cost of premiums can vary considerably. Also remember that you will almost always pay over the odds if you buy from a high-street travel agent.

A one-week single-trip policy with winter sports cover for a 28-year-old man travelling to France could cost as little as £15.88 with Primary Insurance, says Moneysupermarket.com.

For a family of four doing the same trip, one of the most competitive policies is from Flexicover Direct, costing £31.60.

This season, many skiers and snowboarders have tried to claim on their cover for "piste closure" due to the lack of snow. But some have been rejected.

"Many policies specify that all pistes have to be shut for at least 12 hours, if not 24, before a customer can make a claim," says Keith McAdam, spokesman for the Post Office. He adds that most insurers insist policyholders get written confirmation from the resort that the piste was closed for the specified period.

Post Office winter sports insurance will pay compensation up to a maximum of £300 - £20 per day. This rises to £50 a day with insurers such as Marks & Spencer, Greenbee and Argos.

The patchy snow of the past few months has lured many skiers into straying from the relative safety of the piste. However, they may also be taking a chance with their finances.

"Travellers should be aware they run the risk of being uninsured if not accompanied by a qualified instructor," says Prudential's Phil Southgate.

Also be careful about having a glass or two of "vin chaud". "Nearly every policy includes a clause that if you were under the influence of alcohol or drugs at the time an accident occurred, you may not be able to claim," says Peter Gerrard at Moneysupermarket.

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