Size guide
The best dog car restraint by size and breed
Last updated: 2026-09-22
The right restraint depends on your dog's size and strength, not the exact breed. Small breeds need a snug harness and a short strap; large, powerful breeds need heavy-duty gear or a crate. One adjustable seat belt (45–78cm) plus the right harness covers most dogs.
The quickest way to keep your dog restrained and legal is an adjustable 3-in-1 dog car seat belt that clips into any standard seatbelt socket.
Small and toy breeds
Chihuahuas, Frenchies, Yorkies and similar: a snug small-breed harness and a short strap so they can't slip into the footwell. Our belt shortens to 45cm. See our guide to securing a small dog or puppy.
Medium and large breeds
Spaniels, Border Collies, Labradors, Retrievers and similar: a heavy-duty harness and a strong restraint on a back seat. Our belt extends to 78cm with heavy-duty webbing and a steel clip.
Giant and very strong breeds
German Shepherds, Rottweilers, Great Danes and similar: consider a crash-tested crate or the boot behind a sturdy dog guard for maximum protection, or a heavy-duty harness and restraint if travelling on a seat.
Frequently asked questions
Which car restraint is best for a French Bulldog?
A snug small-breed harness and a short seat belt restraint. Our belt adjusts down to 45cm, which suits Frenchies and similar small breeds.
What about a Labrador or German Shepherd?
A heavy-duty harness with a strong restraint suits most large dogs on a back seat. For the very largest or strongest, also consider a crash-tested crate or a boot with a dog guard.
Does one seat belt really fit all sizes?
The restraint adjusts from 45cm to 78cm, covering most dogs. The key is pairing it with a correctly sized harness for your dog.
Sources: UK Highway Code, Rule 57. Guidance only — not veterinary or legal advice.