If you fall ill on holiday, or require treatment or an air ambulance back to the UK, costs could easily run into thousands of pounds. An air ambulance from the east coast of America, for example, could cost between £35,000 and £45,000, according to the Foreign and Commonwealth Office (FCO). TravelSupermarket recommends ensuring that you are covered for medical expenses of at least £2million – and checking if your policy will pay for an air ambulance back to the UK should you need one.

If you are travelling to Europe, you must also ensure that you take your free EHIC (European Health Insurance Card) with you. This will give you the same rights as local residents to medical care, although it doesn't include things like emergency repatriation.

And if you can’t go, you will generally stand to lose the money paid out for your trip.

Cancellation cover will protect you against this, as long as you have it when the event occurs. That’s why it’s vital to buy your travel insurance when you book your holiday. This way, you will be covered for anything that happens in the run up to your trip as well as during it.

Always ensure that cancellation cover is equal to or greater than the value of your booked travel arrangements.

Abandonment cover: With every travel insurance policy, there are certain things that are included as standard and others for which you must pay more.

Buying a policy with abandonment cover means you would be financially protected if you turned up to the airport and then suffered a delay that resulted in you having to abandon your trip. The minimum length of delay you would have to experience to make a claim will be stated in your policy terms and conditions.

Baggage cover: Arriving in your destination to find that your baggage has been lost or delayed isn't the best start to your holiday. And if you are unfortunate enough to have your bag stolen, it could cost a small fortune to replace everything.

Baggage cover will protect you against this. But be aware that there will be a maximum amount you can claim, as well as a single-item limit for individual items. TravelSupermarket recommends baggage cover of at least £1,500.

Catastrophe cover: Remember the Icelandic ash cloud? This type of cover will protect you against catastrophes such as that prevent you getting home. Events that are likely to be covered include earthquakes, volcanoes and tsunamis. Always double check for any exclusions, though.

Delayed departure: It's frustrating arriving at the airport to find that your flight has been delayed.

Cover for this eventuality will reimburse you based on the length of time you are delayed – as long as that is greater than the minimum delay stipulated in the policy terms.

Enforced stay abroad: This cover will protect you financially if you are unable to return home on your scheduled flight due to problems such as airport closure.

Hijack: While this kind of eventuality may sound far-fetched, hijack cover means you would be financially protected if your transport was hijacked and your holiday delayed.

Legal expenses and advice: If you suffer injury while abroad, legal expenses and advice cover could prove invaluable – especially in countries where legal aid isn't an option.

Missed international departure: Even if you do everything in your power to catch your scheduled flight, circumstances beyond your control may mean that you miss it. To put in a claim for missed international departure, you would need to provide written support of what happened and prove that you did everything in your power to catch your flight.

Mugging: This will compensate you if you are mugged while abroad and need hospital treatment.

New-for-old: If your policy includes new-for-old cover, the insurer will replace stolen or destroyed items with brand new ones.

Personal liability: This covers you (up to a certain amount) if you accidently injure a third party or damage their property and end up getting sued.

Personal money: If money is stolen from you while on holiday, your insurer will compensate you for a specified amount – typically between £200 and £500. This doesn't mean you can be careless, though. Insurers expect you to look after your money, and many won't compensate you for money stolen from your hotel room unless it was locked away in a safe.

Pet care: Cover for your pet protects you financially if your furry friend needs in-patient treatment from a vet while you are on holiday due to accidental injury.

Sports cover/adventure cover/specialist sports activities: Many travel insurance policies won't cover you for sports and adventure activities due to the level of risk involved. So if there are specific activities you are planning on doing while away, it’s worth reading the small print of your policy to find out if they are covered. If not, you will need to take out a specialist policy or pay a small additional cost to add it to your existing one. Read the guidance in your documents, and remember to shop around – different insurers have different rules.

Temporary or emergency passport expenses: This type of protection covers you if you have to get a temporary or emergency passport while away due to your passport being lost or stolen. It may include paying out for extra travel and accommodation while you are organising the replacement.

Valuables cover: Remember to check the single-item limit on your policy for valuables such as a tablet, jewellery or smartphone. The policy will only allow you to claim back the amount stated, even if your item is worth more.

Single-trip/multi-trip: As you might expect, a single-trip policy does provides you with cover for one, specific trip. However, if you are taking two or more trips over the course of a year, it may be more economical to buy a multi-trip annual policy. This means that you can take a number of trips over the course of 12 months without needing to take out separate policies each time.

Exclusions: Every policy has exclusions and it's important that you are aware of exactly what they are before purchasing.

Common exclusions include risky winter sports and claims for drink- or drugs-related incidents. If you want to take part in excluded activities, you therefore need to look into taking out a specialist policy or adding extra cover to your existing one.

Excess levels: All policies will have some form of excess, which is the amount an insurance company will deduct from any claim you make. Excesses can be as high as £250 and as low as zero, but will vary from policy to policy and across the areas of cover. That’s why it’s essential to check them! Generally speaking, the cheaper the policy the higher the level of excess you will have to pay.