This is an urgent wake-up call for anyone travelling to Europe this summer - there is a way to get totally free medical cover for you and your family in 27 European countries.

It is called the EHIC, or European Health Insurance Card, and there's more to it than meets the eye. If you've already got one, beware - many older ones are no longer valid.

The totally free card is valid for three to five years and entitles you to free or discounted medical treatment in state-run hospitals in EU countries, plus Iceland, Liechtenstein, Norway and Switzerland.

Does it make all treatments free?

No. You get identical treatment to the locals, so if they pay, you pay the same; if they get it free, you get it free. It is also worth noting the EHIC doesn't cover you if you're going abroad specifically to get treatment.

Who needs one?

Everyone who is going to Europe should pocket one. My own was a godsend at an Italian friend's wedding, when I was due to make a speech and lost my voice, so I nipped to the local GP at no cost.

Some card tips

● Ensure your card is valid.

If you already have an EHIC, check the date at the bottom right to see if it's still valid - up to three million people are carrying expired cards. You can apply for a new one up to six months ahead. If you are still carrying the EHIC's predecessor, the E111, this was phased out in 2005, so yours is definitely out of date.

● Children must have their own cards.

Every family member needs their own. List all under-16s as "dependents" on your application form.

● Keep it with you at all times.

Absurdly, the terms stipulate you are only covered if you show the card. You may think your chances of getting ill on holiday are slimmer than Kate Moss on a diet, but be prepared - do not leave it behind at the hotel if you're out and about.

● You may need to pay and claim later.

Though the EHIC covers instant free treatment in some countries, in others you'll need to pay and reclaim while you're there, or back in the UK. Call the NHS Overseas Healthcare Team on 0191 218 1999 if you need to make a claim.

Is it a substitute for travel insurance?

Absolutely not. It is only about medical cover and should never be seen as a substitute for travel insurance. In fact, it's best to have both as there are areas in which they don't overlap. For example:

● Using the EHIC doesn't always mean free treatment.

You may still have to pay a fair whack even for state treatment in some countries - travel insurance should cover this extra (using the EHIC may mean you needn't pay an excess).

● State hospitals might not be available.

While in the UK emergency treatment tends to be on the NHS, don't assume this type of coverage will always be available everywhere - you may be taken to a private hospital.

● Cancellation, delay, repatriation, baggage loss and theft aren't covered.

The EHIC is purely a medical policy, yet travel insurance covers many other areas. So get both - after all, these days you can get a policy covering a year's European travel for just £14. Visit my site, www.moneysavingexpert.com/travelinsurance, to discover the best buys.

Country-by-country guide

Here's a quick run-down of the typical situation in the main holiday destinations:

● Spain. State healthcare is free, but check they accept your EHIC first as some hospitals and health centres also offer private healthcare.

● Greece. See an IKA-ETAM doctor or dentist to get reduced or free treatment. Consult a private doctor and you'll need to pay charges up front, although you should then be able to claim from the Greek authorities.

● France. Make sure the doctor's registered with France's state healthcare provider before making an appointment. You should be able to claim about 70 per cent of the treatment fees.

● Portugal. There's no charge for state doctors, dentists or hospitals. If you need a pharmacy, you'll find them across Portugal, open Monday to Friday.

See the full guide at www.moneysavingexpert.com/ehic for info on all the countries covered.

How do I get one?

Either apply at www.ehic.org.uk, ask for an application at the Post Office or call 0845 606 2030. If your card's lost or stolen call 0845 605 0707, or 0044 191 212 7500 from overseas.

Yet one final word of warning. Don't search for "ehic" online to apply, as nasty reviewing services charge you a tenner to process your application, and all they do is forward your information to the official site.