Choosing the right one for your trip may sound straightforward enough, but it's essential that you check that your destination is actually covered.

If, for example, you are travelling to Egypt or Turkey, there is no guarantee you will be covered by a European policy. While most insurers include these countries as part of Europe, others such as the Post Office don't cover either in their European policies. Other places to be particularly cautious about include Tunisia, Morocco and Israel.

The European Health Insurance Card (EHIC) entitles you to state medical care in all European Economic Area (EEA) countries, under the same conditions as local residents.

The card is free and can be obtained by visiting the NHS website. So don’t get caught out by online companies offering the card for a fee.

It's important to recognise that while the EHIC offers some protection should you fall ill while on holiday the EU, travel insurance is still essential to protect you against other possible eventualities such as cancellation, baggage loss and delay. As repatriation costs are not covered by the EHIC, and some insurers will waive the excess on medical claims if you have a valid EHIC card, travel cover is important for medical reasons too.

Many standard policies won't permit you to stay for more than 31 days in one destination. And that means your cover will no longer be valid if you stay longer than this. Some insurance companies do cover longer holidays as standard, but check the small print so you're not caught out.

If you're going to be doing a lot of travelling, such as a backpacking adventure or gap year, you can get specialist policies to cover this. Gap year insurance typically gives you cover for 12 months, and allows you to visit multiple countries – again generally with a cap on the length of time you can spend in each country.

If 31 days is sufficient for your trip, however, you can choose between a single-trip policy or a multi-trip annual policy. If you are planning on taking two or more holidays in a 12-month period, a multi-trip policy annual policy is likely to prove more cost effective in the long run – even if it costs more than single-trip cover.

Multi-trip policies also give frequent travellers the freedom to book a last-minute holiday without worrying about travel insurance.

While you may be tempted to buy the cheapest policy available, this could prove a false economy and leave you under-insured. That’s because you will lose out if you have to make a claim of which you receive only a small percentage or on which you have to pay a very large excess. Spending a few extra pounds now could save you thousands in the long run!

TravelSupermarket recommends you look for at least the following levels of cover when choosing a policy:

• £2million for medical expenses
• £1million personal liability
• £3,000 cancellation (or enough to cover the total cost of your holiday)
• £1,500 baggage
• £250 for cash
• Policy excesses under £100
• Cover for scheduled airline failure or end supplier failure (as appropriate) if you are not going on an ATOL-protected package holiday
• Delay cover

Have you read the small print?

Finally, it is absolutely essential that you read the small print of your policy. No two are the same, so it always pays to check the terms.

Even if it is something that you consider to be minor or irrelevant, not doing so could invalidate your policy and lead to a claim being refused – even if it involves an unrelated condition. Insurers have the right to request access to your medical files, so make sure you are honest from the start.

Read our guide to travel insurance with pre-existing medical conditions and use our dedicated search tool to help you find a suitable quote.