A dog’s microchip is implanted just under the skin between the shoulder blades, slightly to the right of the spine, in the loose skin at the base of the neck. That is the standard site in North America and the first place any vet or shelter will scan.
It goes in subcutaneously — under the skin, not into muscle and not near any organ. The chip itself is a passive RFID transponder about the size of a grain of rice, roughly 12mm long, with no battery and no moving parts.
Why that spot
Three reasons, and they are all practical:
Loose skin
There is enough slack there to lift a fold and place the chip cleanly with minimal discomfort.
It stays put reasonably well
Away from joints and high-movement areas, the chip is less likely to travel.
Everyone knows to look there
A standard site means a vet in another state scans the right place first. That consistency is the whole point.
Cats are chipped in the same place. Horses are different — the chip goes into the nuchal ligament on the left side of the neck — and other species have their own conventions.
How it is implanted
With a needle, in a few seconds, during a normal appointment. No anaesthetic and no surgery. The needle is wider than a vaccination needle, so most dogs react roughly the way they react to a shot — a flinch, then it is over.
It can be done at any age from a few weeks old, and is often combined with a vaccination visit or with spay and neuter surgery, when the dog is already under anaesthetic for something else.
Does a microchip move?
Yes, sometimes. It is called migration and it is common enough to matter.
A chip can drift from the implant site — down a shoulder, along the chest wall, occasionally as far as an elbow or the base of the neck. It is not painful and it does not harm the dog. What it does is make the chip harder to find.
This is why a proper scan covers the whole body in an S-pattern rather than a single pass between the shoulders, and why it is worth asking your vet to scan at routine visits. A chip that has migrated and a chip that has failed look identical to a rushed scan.
Can you see or feel where the chip is?
Sometimes you can feel it; you will almost never see it. In a thin, short-coated dog you may find a tiny firm grain by rolling the loose skin gently between finger and thumb. In most dogs you will feel nothing at all.
There is no visible mark after the first few days, no bump in most animals, and no tattoo. Not being able to feel one tells you nothing — only a scanner can confirm a chip is there.
What about a lump at the site?
A small firm swelling in the first days after implanting is usually normal healing. A lump that grows, stays hot, or appears long afterwards is worth a veterinary look. More on lumps at the microchip site.
Does it ever need replacing?
No. A microchip has no battery, so there is nothing to run down. It draws its power from the scanner’s radio signal for the fraction of a second it is being read, and is designed to last the animal’s lifetime.
Chips do occasionally fail or become unreadable, which is another argument for having your dog scanned at routine appointments rather than assuming.
The part that happens after the chip goes in
Knowing where the chip is matters far less than whether the number leads anywhere. The chip stores one thing: a unique identification number. No name, no address, no phone number, no location. Everything useful lives in a registry — and only if somebody put it there.
An unregistered chip returns a number with no owner attached. The scan works perfectly, the number appears on the screen, and the trail stops.
Register with the registry your pet’s microchip actually belongs to. Every chip carries a manufacturer prefix, and each manufacturer has an associated registry. A nominal fee is required. Registering there means that when a vet or shelter looks the number up through the standard tools, it resolves to you.
And keep it current. A record with a phone number from two moves ago is the same as no record at all.
- Look up a microchip number
- What a microchip does, and what it cannot do
- Transfer a chip registered to a breeder or shelter
- Side effects of microchipping
Register your dog’s microchip with Peeva
Common questions
Where exactly is a dog’s microchip placed?
How deep does the microchip go?
Does microchipping hurt a dog?
Can a microchip move after it is implanted?
Does a dog microchip need to be replaced?
Where are cats microchipped?
Microchip resources
Find the registry by microchip prefix · Look up a microchip number · Universal microchip scanners · Register your pet’s microchip · More microchip questions, answered
