Animal Welfare Assistant Theresa scans a GSD for a microchip

Microchipping your dog

What is a microchip?

A pet microchip is a tiny computer chip that’s about the size of a grain of rice. It contains a unique code that matches up to your pet’s details.

Microchipping a dog is a quick and simple procedure. The chip is inserted under a dog’s skin, usually around the scruff of the neck, using a needle. It takes seconds.

Animal Welfare Assistant Theresa scans a GSD for a microchip
We scan all pets for microchips at Blue Cross

Dogs can be checked for a microchip using a handheld electronic device, called a scanner. When this is waved over the dog’s neck, the scanner will recognise the unique information held inside the chip.

Why should I get my dog microchipped?

A microchip is a permanent form of identification. As long as the details are kept up to date, you can always be contacted if your dog goes missing.

When dogs are found straying they are collected by the local authority dog warden and kept for seven days. If your microchipped dog goes missing and is taken in by the dog warden, your contact details will be easily found and you can come and collect them straight away, even if their collar and ID tag have fallen off.

But without identification telling the dog warden who your dog belongs to, they cannot let you know your beloved pet has been found. After seven days your dog can be passed to a rehoming charity, such as Blue Cross, to be found a loving new home, or they can be euthanised by the local authority.

Each year we look after many dogs who we know must have come from loving homes as they are friendly, affectionate and have had training. But sadly, without a microchip, we have no way of reuniting them with their owners so we find them new loving families instead, even though we know that somewhere out there a heartbroken owner is missing them terribly.

It’s really important to keep your dog’s details up to date, too. We have rehomed dogs whose owners we could not get in touch with because the details on the microchip were not current.

Where can I get my dog microchipped and how much will it cost?

It costs about £10 to £15 to get your dog microchipped by a vet or vet nurse, and some dog groomers, dog walkers and pet sitters offer this service too. Make sure the person who microchips your dog is qualified to do so as your dog may suffer if the person is not properly trained.

Photo of a microchip implanter
Microchips are about the size of a grain of rice. They are put under the skin using an implanter, like this.

Blue Cross microchips dogs, as well as cats and rabbits, for free. Contact your nearest Blue Cross rehoming centre or animal hospital to book an appointment.


How old does my dog have to be to be chipped?

Dogs can be microchipped at any age, but it’s more comfortable for puppies if they’re at least seven or eight weeks old before being chipped.

Under the new microchipping law that came into effect on 6 April 2016, all dogs and puppies must be microchipped and registered by the age of eight weeks.


Will microchipping hurt my dog?

Microchipping is a quick procedure but it does involve a needle so is likely to be uncomfortable for your dog for a few seconds. However, many dogs don’t even notice!

If you think your dog or puppy has had a reaction to a microchip, contact your vet straight away.


What’s the law on dog microchipping?

A Parsons Russell Terrier is scanned for a microchip
When you get a new puppy or adult dog, get your vet to scan them as soon as possible to check the chip works and the details are correct

Since 6 April 2016, all dogs in England, Scotland and Wales must be microchipped. 

As of that date, owners of dogs and puppies over the age of eight weeks must also have registered their pet’s microchip details on one of the authorised databases. These databases are run by private companies, and not by the government or the council.

Dog owners are also required to keep their pet’s details up to date with the database under the new law.

As well as being microchipped, it is still a legal requirement for dogs to wear a collar and tag with the owner’s name and address on it when in a public place.

Owners who do not get their dog microchipped and registered with an approved database face a fine of up to £500 if caught.

The only exception to this law for pet dogs are those who a vet believes should not be chipped for health reasons.

If you rehome your dog to someone else, you must give the new owner the correct microchip registration paperwork so that they can contact the database and register as the dog’s new owner.

Dogs in Northern Ireland are already required to be microchipped as part of the conditions of the dog licence.

Will my new puppy be microchipped before I take them home?

Puppies must be microchipped before they go to their new homes under the new law that came into effect on 6 April 2016. 

The breeder should be the first registered keeper of the puppy – they are breaking the law if they do not register the puppy by the time he or she is eight weeks old. Breeders should also pass on correct microchip paperwork to the new owner when the puppy goes home. 

If you are buying a small or toy breed, such as a Chihuahua, a vet may decide it’s better to wait to get the puppy chipped when they are older and bigger. If this is the case, the breeder must give you a certificate signed by a vet to prove this instead of the certificate of registration. However, there is really no reason for small breeds not to be chipped; kittens are frequently chipped from as young as eight weeks, and they are much smaller than small breed dogs.

If a breeder has not microchipped and registered the puppy before you take them home, and cannot give you evidence to show the reason for the delay, walk away.

Whenever you buy or rescue a puppy or adult dog, you should ask your vet to scan them on your first visit to make sure that the chip corresponds with the paperwork you’ve been given.  Errors can and do happen easily, so always make sure the chip and paperwork match.

Is my dog’s microchip proof of ownership?

No. Under the new Microchipping of Dogs (England) Regulations legislation, the person who primarily cares for the dog and keeps them in their home is called a ‘keeper’, not an ‘owner’.

The dog’s microchip must be registered to the ‘keeper’, who may not always be the owner.

Some rescue organisations used to keep chips registered in the name of the rescue instead of the owner, but under the new law this is no longer allowed. If you rehome a rescue dog, their chip details must be registered in your name. Many rescues will do this automatically when you rehome the dog, but always check.

This means this person has legal responsibility for their dog and can be held responsible if the dog falls foul of any law, including straying or causing injury, but it does not prove legal ownership.

How do I check if my dog’s microchip details are up to date?

A Jack Russell terrier is scanned for a microchip
It's really important to keep the details on the chip up to date. If your dog goes missing and your details are incorrect, you significantly decrease the chances of being reunited with your pet.

When you get your dog microchipped you should receive confirmation from the database your dog’s details are registered with. To check if your dog’s details are correct, simply contact the database that holds the details on your dog’s chip. 

If you don’t have a certificate of registration or other type of confirmation from the microchip database, you can check which database the chip is registered to at

How do I change my dog’s microchip details?

If you move and have a change of address or name, don’t forget to update your dog’s details too. 

To do this, get in touch with the database that holds your dog’s details. Depending on which database your dog is registered with, you might be able to do this over the phone or online, or you may have to do so by post.

The cost of actually getting your dog microchipped covers only the implantation of the chip itself; it doesn’t cover the cost of changing your pet’s details in the future.

Pet microchip databases charge an admin fee of between £6 and £20 to change and update dogs’ details. Some will charge you each time you want to change your details, and others charge an upfront fee that covers all changes for the whole of your dog’s life. Check with your database to find out how they are administered.

If you don’t keep your details up to date, the chances of you being reunited with your pet if they go missing significantly decrease. Don’t run the risk of never seeing your dog again.

— Page last updated 12/07/2021