Microchips and Identification

Most pets that go missing are found by an ordinary member of the public within a mile or two of home. Whether they get back to you depends on one thing: how quickly the finder can identify who they belong to. That is the whole job of identification, and it is worth ten minutes of admin a year.

How a microchip works

The chip is an inert glass capsule about the size of a grain of rice, implanted under the skin — between the shoulder blades in dogs and cats, and in different sites in other species. It carries no battery and no tracking function. When a scanner passes over it, it returns a unique 15-digit number, which is looked up on a database that holds your contact details.

Implanting takes seconds and needs no anaesthetic. Vets, rescue centres, dog wardens and many councils scan routinely, so a chipped animal handed in anywhere in the country can usually be traced within minutes.

The part owners forget

A chip with out-of-date details is a dead end, and stale records are the single most common reason a found pet is not reunited. Update the database when you:

• move house or change your mobile number or email address
• rehome or take on a pet from somebody else, so the record is transferred rather than just amended
• take over care of an animal from a family member

Add a second contact — a relative or a friend at a different address — so there is a fallback if you cannot be reached. And keep the chip number itself somewhere you can find it, along with the name of the database, in the same folder as vaccination records.

The legal side in the UK

Dog microchipping has been compulsory across the UK for years, and cat microchipping became a legal requirement in England in June 2024. Rules differ between England, Scotland, Wales and Northern Ireland and are updated from time to time, so check the current official guidance for the nation you live in rather than relying on what a breeder or a website says.

Separately, a dog in a public place must wear a collar with the owner’s name and address on it or on a tag. A phone number is sensible too. Leave the dog’s own name off — it makes it easier for a stranger to call the animal away.

A sensible second layer

Visible ID works before a scanner is involved: an engraved tag on a dog, a quick-release collar and tag on a cat that tolerates one. For rabbits, small furries, birds and reptiles, keep clear photographs showing markings, plus any ring or chip number, so an ownership claim can be supported.

Ask for the chip to be scanned at the annual check. Chips occasionally migrate or, rarely, fail, and it is better to discover that now than on the day your pet goes missing.