Every year, pets slip out open doors, squeeze under fences or bolt during storms and fireworks. Collars and tags are the first line of defense, but they can fall off. A microchip is a permanent form of identification that stays with your pet. Understanding how it works, and what it requires from you, helps ensure it does its job.
What a Microchip Is
A pet microchip is a tiny device, roughly the size of a grain of rice, implanted under the skin, usually between the shoulder blades. It is inserted with a needle in a procedure similar to a routine injection, and it does not require surgery.
Most pet microchips use radio frequency identification. They have no battery and do not transmit continuously. When a scanner passes over the chip, it reads a unique identification number.
What a Microchip Does Not Do
A common misunderstanding is that a microchip is a GPS tracker. It is not. A standard microchip cannot show you where your pet is. It only works when a lost pet is found and scanned, typically by a veterinary clinic or animal shelter.
The chip also does not hold your contact details. It holds an ID number. That number is linked to your information through a registry database, which is why registration is essential.
Registration Is the Part People Skip
A chip that is not registered, or that is registered with an old phone number, may not lead anyone back to you. Common problems include:
- The chip was implanted but never registered
- The pet was adopted or rehomed and the registration was never transferred
- The owner moved or changed phone numbers and never updated the record
If you are not sure where your pet’s chip is registered, the American Animal Hospital Association offers a free universal pet microchip lookup tool at aaha.org that searches many participating registries by chip number. Your veterinarian can scan your pet to find the number if you do not have it.
A Simple Annual Check
Make microchip checks part of your routine:
- Ask your veterinarian to scan the chip during the annual exam to confirm it still reads
- Log into the registry and confirm your phone number, email and address
- Add a secondary contact, such as a family member, in case you cannot be reached
- Keep the chip number with your pet’s records and in your phone
Microchips rarely migrate far or fail, but scanning occasionally confirms everything is working.
Chips and Tags Work Best Together
A visible ID tag lets a neighbor call you right away without a scanner. A microchip is the backup if the collar comes off. Using both gives your pet the best chance of a quick reunion. Indoor cats benefit too, since even the most homebound cat can slip out. Talk to your veterinarian about microchipping if your pet does not already have one.
