Nearly half a million globetrotting doggies, moggies and ferrets have travelled to and from the UK since the introduction of the Pet Travel Scheme (PETS) in February 2000 - and the numbers are rising.

In the first month of the scheme - which allows pet owners to take their animals on holiday without lengthy stays in quarantine - 619 cats and dogs entered the UK, but in May this year the total was 10,117 (1,714 cats, 8,455 dogs and 8 ferrets).

But despite the growing popularity of pet travel, the process is neither easy nor cheap. To take your pet abroad and return to the UK, you must have a pet passport. To qualify your cat or dog must be at least three months old, microchipped and vaccinated against rabies. A vet needs to take a blood test 28 days later to check the vaccine is working- if it is, your pet is considered fit to travel; if not, it must have another vaccine. It also needs a booster every three years.

Pet passports need to be planned in advance if you are determined to take Fido on your two-week European break. While he will be allowed to leave the UK after a clear blood test, you cannot bring him back in until six calendar months have passed from the date that the sample was taken. The Department for Environment, Food and Rural Affairs (Defra) oversees the scheme - check its website for up-to-date information on vaccination and any rule changes.

The total cost of getting your pet microchipped and vaccinated, and then later flea and tick-treated abroad before you come home again (not less than 24 hours and not more than 48 hours before your return journey) is up to £200. But shop around for the best deal. For instance, you may be able to save money on microchipping by going to your local authority's dog warden, rather than a vet.

The next hurdle is pet transport as few carriers will take them. Brittany Ferries charges £15 per animal from the UK to France, and £22.50 for the trip back; to Spain it costs £25 out, and £35 back. P&O Ferries, which last year carried 20,000 pets, charges £15 each way from Dover to Calais.

With Eurotunnel you pay £30 to take your pet to and from France, but your pet must stay inside your car for the journey, something that most ferry companies also insist on.

Eurostar will not accept pets, and many airlines balk at the prospect of four-legged cargo. Those airlines which do accommodate pets charge high prices. Thomsonfly and Monarch give rough estimates of £745 to fly a small dog to Spain and back, and £775 to Italy and back.

British Airways World Cargo says its prices depend on the height and weight of your dog. It also requires you to have an approved container and, to get a quote, you must give its dimensions and its combined weight with the dog. Thomas Cook also says that it needs to know the height, weight and breed of dog first.

If your pet falls ill or is injured while you are away, some insurers will allow you to claim for veterinary care abroad, but check the small print. For example, Pinnacle Pet Insurance will cover your pet for up to £750 for a maximum of 90 days a year in countries governed by PETS. Crufts Pet Insurance will pay up to £250 for treatment per trip - with a maximum of three trips a year of up to 30 days.

Melanie Matthews, of Halifax Pet Insurance, says that you should take your policy documents with you in case you need to claim. If you are in the UK, Isle of Man or the Channel Islands, she says that her company will locate the nearest vet “so have our telephone number handy”.

But the most important consideration is whether your pet will enjoy being abroad. Give particular thought to the climate. After all, it won't be you wearing a fur coat in the sun.

Useful websites: www.defra.gov.uk , petsawayuk.co.uk , jets4pets.com

Paws for thought

Before you take your pet abroad you need to think about:

Limitations Will your pet limit the activities you can take part in while you are away? For example, having a pet may restrict your eating out as many restaurants are unlikely to welcome Fido or Felix.

Overall cost How expensive are vaccinations? Will you have to transport large quantities of its food, its bed or any other essential comforts? Does your hotel charge extra for a pet?

Accommodation Are pets welcome at your hotel? Perhaps you should consider a break in the UK where there are plenty of pet-friendly hotels.

Research How are pets regarded in your holiday destination? The UK is a nation of animal-lovers but not all cultures see pets in the same light.

Alternatives/stress How long are you going for? Is it worth the fuss and expense? And will the pet find the experience stressful? If you think that it will, consider putting it in a cattery/kennels in the UK.

Can you save on their treatment abroad?

You can now travel overseas to get cheaper medical treatment, but can you also cut costs on Fido's care while you are away?

Some items for your pet may be worth getting overseas. Mark Hurst, of the Barrow Hill Veterinary Practice, in Ashford, Kent, says that Frontline, the flea treatment, is significantly cheaper in Europe: “We have lots of clients who buy it abroad. Buying standard drugs on the Continent is certainly going to save you money too.”

However, treatment is a different matter, as you may be cutting costs at the expense of care. “Even if I wasn't a vet, I still would not advocate taking pets abroad for treatment,” says Mr Hurst. “Medical practices in Greece, for example, can make the most basic UK practices look like palaces. Having said that, some of the vets in Holland are fantastic - the Utrecht Veterinary School is amazing.”

You could make some savings, once you're happy with the standard of care. For example, at a practice in Brussels you could pay €35 for an X-ray, €25 for an anaesthetic, which many pets need first, and a €25 consultation fee - that's a total of €85, or just over £67. You would pay almost as much for an X-ray, alone, in many British practices.

One last thing: be careful that travel costs don't outweigh any savings.

Case Study: Chica prepares for take-off

Jeni Russell, 56, and her husband Michael, 57, the proud new owners of Chica, a 14-week-old Jack Russell-chihuahua cross, are about to start the process of getting a pet passport so that he can join Boswell, the family's Jack Russell, jetting around the world between the family's bases in Antigua, Portugal and Cornwall.

Mrs Russell, left, who formerly worked for British Airways, says that getting the passport is not a problem, just “quite long-winded”. The requirement for a recent flea and tick treatment - not less than 24 hours and not more than 48 hours before departure - can make coming back difficult.

Passports for Chica and Boswell cost about £165 initially; visits to a vet in Portugal for the flea and tick treatment costs between £20 and £40.

Travel can be complicated. Although Portugal is easy as they go by car, it is the flights to Antigua that dent the budget the most. The bill for Boswell is £1,600 return with British Airways. Mrs Russell says: “It would be cheaper with Air France - about €70 from Paris - and the dog can be in the cabin with me. But I would have to take about four different flights.”