Best Age to Microchip a Puppy or Kitten
Chipping your puppy or kitten is usually the breeder's job before sale, but the deadlines differ for dogs and cats, and small or unwell pets can sometimes wait.
A new puppy or kitten brings a short list of first things to sort, and microchipping sits near the top of it. The timing is mostly decided for you, because the law sets the deadlines: in England, Wales and Scotland, dogs must be chipped once they’re older than eight weeks, and in England cats must be chipped once they’re older than 20 weeks. If you’re booking the appointment yourself, our guide to what to expect when microchipping a puppy or kitten walks through the visit itself.
When to microchip a puppy
In England, while a puppy is still with its mother, the law treats the mother’s owner as the keeper. In practice that means the breeder is responsible for chipping and first registration before the puppy changes hands. So when you collect a puppy, you should expect it to be chipped already, and your part is transferring the registration into your name. There’s more in our guide to whether puppies and kittens must be chipped before sale and our breeder’s guide to microchipping a litter.
When to microchip a kitten
The 20-week threshold was chosen to coincide with neutering age, according to the Commons committee that examined the law in April 2023. Many kittens are chipped at the same visit as being neutered, so one trip can cover both. Breeders usually chip kittens before they leave for new homes at around eight weeks.
If your kitten is already home and unchipped, there’s no reason to wait. Book it in whenever suits, and register the chip with your details once it’s done. Our guide to where to get a puppy or kitten microchipped covers vets, charities and costs.
Is there a minimum age for microchipping?
There’s no minimum age for microchipping, and a dog or cat can be chipped at any age. Most vets suggest around seven to eight weeks for puppies. The Royal Kennel Club says chipping very young puppies may be uncomfortable, and the chip is more likely to migrate.
When a vet suggests waiting
Small size is one reason for a delay. The British Small Animal Veterinary Association (BSAVA) says most dogs and cats can be safely chipped before the eight or 20-week deadlines. In toy or miniature breeds, a vet may judge that chipping should wait a few weeks while the puppy or kitten grows.
A vet can also give a very small puppy, or one with certain health problems, a temporary exemption certificate so chipping can wait until the pet is a little older. If you’re buying a puppy or kitten with an exemption, the breeder should give you the certificate signed by the vet. It replaces the usual registration paperwork, so keep it safe — it explains why your pet isn’t chipped yet.
Register the chip in your name once it's in
Once your pet is chipped, the next step is making sure the record holds your details, not the breeder’s or the rescue’s. The chip itself only holds a 15-digit number: the owner’s name, phone number and address sit on a database linked to that number, so a scanned chip only reaches you when the record is in your name. You can register your pet’s microchip with Pet Database once you have the number from the vet or breeder.
Common questions
My puppy or kitten came from abroad. When does it need a chip?
Imported dogs and cats have a shorter deadline than the usual ones. If you import a dog or cat into England, you must have it microchipped within 30 days of its entry, whatever its age. The normal eight-week and 20-week thresholds don’t delay that, so book the chip as part of settling your new pet in, and register it straight after.
What happens if a puppy or kitten misses the microchipping deadline?
In England, an authorised person can serve the owner of an unchipped dog or cat a 21-day notice to have it chipped. Ignoring that notice is the offence, punishable by a fine of up to £500. Scotland and Wales have a similar notice route for dogs, with the same maximum fine if a notice is ignored.
What happens when the exemption certificate expires?
In England, an exemption lasts only for as long as the vet’s certificate runs, and the certificate itself shows how long. When it expires, the pet must be chipped unless a vet issues a further certificate because they still have health concerns.
The age you chip at matters less than what happens next. Once the chip is in, you can register your pet with Pet Databaseso the number points to your name from the start.
