The Short Answer

A microchip doesn't track your cat like GPS — it's a permanent ID that proves ownership when your cat is scanned. To use a microchip to find your lost cat, you need to: (1) ensure it's registered, (2) notify the registry, (3) alert shelters and vets, and (4) keep searching actively.

How Microchips Work

A microchip is a tiny RFID chip implanted under your cat's skin. It contains a unique 15-digit number. When scanned by a vet or shelter, the number links to a registry with your contact information.

Important: Microchips are NOT GPS trackers. They don't show your cat's location. They only work when your cat is scanned at a vet or shelter.

Step 1: Find Your Microchip Number

If you don't know your cat's microchip number:

  1. Check your adoption or vet paperwork.
  2. Call the vet who implanted the chip.
  3. Take your cat to any vet for a free scan (if your cat is still home).
  4. Check your cat's adoption records from a shelter.

The number is 15 digits (ISO standard) and starts with a country code or manufacturer code.

Step 2: Identify the Registry

Different microchip manufacturers use different registries. Use our microchip lookup tool to identify the registry based on the chip number prefix:

  • 9851xxxx — 24PetWatch (formerly HomeAgain).
  • 9810xxxx — PetLink/Bayer.
  • 9820xxxx — Datamars/PetLink.
  • 956xxxx — Avid ID.
  • 9000xxxx — Various European registries.

Step 3: Check Your Registration

Call the registry and verify your contact information is current:

  • Your name and phone number.
  • Your email address.
  • Your current address.
  • Emergency contact information.

If your info is outdated, update it immediately. An unregistered or outdated chip is useless.

Step 4: Notify the Registry of Your Lost Cat

Most registries have a "lost pet" alert system:

  1. Log into your registry account.
  2. Mark your pet as "Lost."
  3. Upload a current photo.
  4. Add details: last seen location, date, contact info.
  5. The registry will alert local vets and shelters in your area.

Step 5: Alert Local Vets and Shelters

Call every vet and shelter within 5 miles (10 miles for rural areas):

  • Provide your cat's microchip number.
  • Give a description and photo.
  • Ask them to scan any found cat for your chip.
  • Leave your contact info.
  • Follow up weekly.

Most vets and shelters scan every found cat for a microchip — this is how most microchipped cats are returned.

Step 6: Register With Multiple Registries

Don't rely only on the manufacturer's registry. Register your chip with multiple databases:

  • HomeAgain — widely used in the US.
  • PetLink — free for life.
  • Avid ID — established registry.
  • FoundAnimals — free, by Michelson Found Animals.
  • AKC Reunite — covers cats too.

This increases the chance that a finder can reach you.

Step 7: Keep Searching Actively

A microchip is a backup — not a replacement for active searching. Continue:

  • Posting your lost cat alert on Cat Reunite.
  • Distributing flyers within 1 mile.
  • Setting up humane traps.
  • Searching at dawn and dusk.
  • Checking shelters in person weekly.

What Happens When Your Cat Is Scanned

  1. A vet or shelter scans your cat — the chip number appears.
  2. They look up the number in the AAHA Universal Pet Microchip Lookup tool.
  3. The tool identifies the registry.
  4. The vet/shelter calls the registry.
  5. The registry contacts you (using your registered contact info).
  6. You arrange to pick up your cat.

This is why keeping your contact info updated is critical.

Common Microchip Mistakes

  • Not registering the chip — the chip is useless without registration.
  • Not updating contact info when you move or change phone numbers.
  • Not knowing the chip number — keep it in your records.
  • Relying only on the chip — continue active searching.
  • Not registering with multiple registries — increases recovery odds.
  • Not notifying the registry your cat is lost — they can alert local vets.

FAQ

Can a microchip track my lost cat?

No — microchips are not GPS trackers. They're RFID chips that only work when scanned at a vet or shelter. For real-time tracking, use a GPS collar (Tractive, Fi, Air Tag).

How long does a microchip last?

Microchips last the lifetime of your cat. They don't have batteries and don't need replacement.

What if my cat's microchip isn't registered?

Register it immediately. An unregistered chip is useless. Contact the manufacturer or use a universal registry like FoundAnimals (free).

Can a microchip migrate or stop working?

Microchips can migrate slightly but rarely fail. Have your vet scan it annually during checkups to confirm it still reads.

How much does microchipping cost?

Typically $25-75 at a vet. Some shelters and rescue groups offer low-cost microchipping events for $10-25.

Take Action Now

If your cat is microchipped, contact your registry today. If not, schedule microchipping with your vet. Post your lost cat alert and use our microchip lookup tool. Read: Microchipping Guide.