Saint Bernards are the most expensive breed with bills, including vets and food, costing a total of £25,808.

Another whopper, the Newfoundland, racks up £24,274.

Annual outgoings include £1,058 on food, £276 for vet bills and £420 for grooming.

Beagles were among the cheapest breeds but still set owners back an average of £15,707 over a lifetime. 

The research was compiled by comparethemarket.com in collaboration with star of Vets in Practice, author Emma Milne.

She said: “Having a dog can be one of life's most rewarding things but, as the saying goes, it isn't just for Christmas. The harsh reality is there are hundreds of dogs left abandoned every year.

“We want to highlight what an important decision it is to buy a dog. While it’s right to understand how much a dog can cost, we should always remember that life with a dog is absolutely priceless.”

A Bernese mountain dog will see a lifetime spend of £19,288.

Also appearing among the list of dearest pets was the bulldog, with an annual expense of £1,724, French bulldogs at £1,391 and Great Danes at £2,388.

Whippets join beagles among the least expensive.

Researchers found that six out of 10 Brits would be deterred from buying a dog if they knew it would cost them £25,000.

And 44 per cent would be put off spending £10,000 in a dog's lifetime.

A poll of 2,000 people who do not own a dog estimated a four-legged friend would set them back £880 a year – two thirds the cost of the cheapest breed.

Only two thirds said they would take cost into consideration.

And 14 per cent said they would consider returning a dog if costs became too much.