Few things bring a smile to your face as reliably as a dog poking its head out of the window of a moving car.

Alas it's not only dangerous for your canine pal, it's also illegal and could lose you your licence and invalidate your insurance.

In the event of a crash not only could Bonzo be killed or seriously hurt but you could end up forking out a five-figure sum to repair any damage or injury caused to a third party's property.

Sometimes you can't help travelling with your four-legged chum. This is why a variety of dog harnesses, designed for the car, are readily available.

You wouldn't dream of setting off without strapping in your children so it makes sense to have Rover and Shep secured.

The law

There is no specific law on carrying pets in a vehicle.

But Rule 58 of the Highway Code states:

"When in a vehicle make sure dogs or other animals are suitably restrained so they cannot distract you while you are driving or injure you, or themselves, if you stop quickly. A seat belt harness, pet carrier, dog cage or dog guard are ways of restraining animals in cars."

You could be prosecuted for driving 'without due care and attention' if your driving falls 'below that expected of a competent driver' as a result of being distracted by an animal in the car.

Your insurance

Gocompare.com warns that drivers who don’t restrain dogs and cats while on the move are not just breaking the law, they could also be invalidating their car insurance.

That means if you're in an accident, you could be made to pay for any damage to your car AND any other cars involved, not to mention any medical or other costs resulting - something that could easily add up to a five-figure bill.

Gocompare.com spokesperson Matt Oliver said in the Mirror: "The law is clear – you must secure your animal while in a car – therefore if you don’t do this and an animal roaming freely around the vehicle is said to have contributed to causing an accident, then an insurance company could be well within their rights not to pay out on a claim."

How to protect your pet and ensure you're covered

Fortunately, this is an easy problem to fix. You can pick up a pet seat belt (that clips on to their collar like a lead, then into a seatbelt socket) for less than £4 or a car harness for less than £10.

If you'd rather let them roam free in the boot, pet-barrier safety nets can be found for less than £5.

Gocompare also has the following tips to staying safe travelling with your pets:

  • If you are travelling with a dog, try and take it for a long walk before you set off so it doesn’t have any pent up energy for the journey ahead.

  • Don’t feed your pet for two hours before you travel as many suffer from motion sickness.

  • Restrain your animal properly with a harness, crate or guard. There are many on the market so shop around and see which one is best for your car and your pet.

  • Keep the car cool when driving. Cars can get very hot and cats and dogs are already wearing their coats, so use sun blinds or open a window to make sure they don’t get overheated.

  • Plan your journey for regular breaks. This will allow your animal to go to the toilet as well as have some fresh air.

  • Ensure that your animal has plenty to drink so they don’t become dehydrated.

  • Take a supply of their normal food, in case of a breakdown, or if you are travelling a long way.

  • Never leave an animal alone in a car, especially on hot days, as this could lead to dehydration.