How to check your pet's microchip registration (and update it)

Updated October 13, 2026 · LostPet.com

Short answer

To check your pet's microchip, find the 9-, 10- or 15-digit chip number on your vet or adoption paperwork, or ask your vet to scan it. Enter it in the AAHA Universal Pet Microchip Lookup at petmicrochiplookup.org to see which registry holds it. Then contact that registry to confirm or update your phone and address.

A microchip can bring a lost pet home, but only if the number leads back to you. The AVMA says only about 6 in 10 pet microchips are registered (AVMA, 2024). And in a large shelter study, the usual reason a chipped pet didn't get home was wrong or missing owner information (AVMA).

Checking takes a few minutes. Here's how.

Step 1: Find your pet's microchip number

The number is usually 9, 10 or 15 digits long (AVMA). Look for it on:

vet records or invoices,
adoption papers from a shelter or rescue,
the sticker or card you got when the chip was implanted.

Can't find it? Ask your veterinarian to scan your pet. Most clinics have scanners (AVMA). Find one near you in our vet directory. If you adopted your pet, the shelter may also have the number on file.

Tip: once you have it, save the number in your phone and in your free LostPet.com record.

Step 2: Look it up with the AAHA tool

Go to the AAHA Universal Pet Microchip Lookup and enter the number with no spaces or dashes. The tool checks the participating registries and lists the ones that have information for that chip, with the most recently updated first (AAHA).

Good to know (AAHA):

The tool does not show owner information, and you can't update your details there.
It only searches registries that take part, so a chip registered elsewhere may not appear.
If the chip was never registered, the result may show the company that made or sold it.

Step 3: Contact the registry

Start with the first registry on the list. Ask them two things:

Is this chip registered to me?
What phone, email and address do you have?

If you get no match, work down the list (AAHA).

Step 4: Update your details

Fix anything that's out of date, especially your phone number. The AVMA says to make sure your phone numbers, email and address are all correct (AVMA). If the registry lets you add a second contact, add a family member or friend.

Step 5: Register the chip if it isn't registered

If no registry has your details, register the chip now. Registries are listed on the AAHA lookup site. Some charge fees and some don't, so check before you pay.

Had a "Save This Life" chip? AAHA reports that Save This Life has stopped operating and was disconnected from the lookup tool. If your pet's chip number starts with 991 or 900164, you may need to re-register it with another registry. You don't need a new chip (AAHA).

Step 6: Have the chip scanned once a year

Chips are built to last a pet's lifetime, but the AVMA recommends asking your vet to scan the chip at least once a year to make sure it can still be detected (AVMA).

Step 7: Save a backup record on LostPet.com

Register your pet free on LostPet.com with a clear photo, breed, color, ZIP code, the chip number and your phone. It doesn't replace your chip registry, which is what shelters and vets use. It means that if your pet ever goes missing, everything is ready: you can report your pet lost in minutes, and My Pets can print a flyer with a QR code on the spot.

When to check again

You moved or changed your phone number.
You adopted a pet or took over a pet from someone else.
Before July 4 and New Year's Eve (see our fireworks guide) and before Halloween (see our Halloween guide).
On Check the Chip Day, August 15 (AVMA).

Two chips? It happens. The AVMA says two chips won't interfere with each other, but keep both registered so you can be reached whichever one is scanned (AVMA).

A chip works best alongside a collar and ID tag. Read microchip vs. ID tag and what to put on a pet ID tag. Found a pet with a chip? A vet or local shelter can scan it.

Quick checklist: how to check and update your pet's microchip registration

Find the microchip number. Look on your vet records, adoption papers or the chip paperwork. If you can't find it, ask your veterinarian to scan your pet. If you adopted from a shelter, ask the shelter for the number.
Look up the number. Enter the number, with no spaces or punctuation, at the AAHA Universal Pet Microchip Lookup (petmicrochiplookup.org). It lists the registries that have information on that chip, with the most recently updated first.
Contact the registry. Start with the first registry listed. Ask whether the chip is registered to you and what contact details they have.
Update your details. Correct your phone numbers, email and address, and add a backup contact if the registry allows it.
Register the chip if it isn't registered. If no registry has your details, register the chip with a registry. Check what it charges before you pay.
Have the chip scanned at checkups. Ask your vet to scan the chip at least once a year to make sure it can still be detected.
Save a backup record. Register your pet free on LostPet.com with a photo, description, the chip number and your phone, so everything is ready if your pet goes missing.

Frequently asked questions

Can I look up a pet owner's information with a microchip number?

No. The AAHA lookup tool doesn't show owner information. It only tells you which registry to contact. The registry then contacts the owner or helps connect you, which protects owners' privacy.

Is there one national pet microchip database?

No. The AVMA says the US has no single, central database. Chips can be registered with one or more registries, and each keeps its own records. That's why the AAHA lookup tool checks many participating registries at once.

How do I find my pet's microchip number?

Check vet records, adoption papers or the paperwork you got when the chip was implanted. If you can't find it, ask your veterinarian to scan your pet. Most vet clinics have scanners. If you adopted from a shelter, the shelter may have the number on file.

Is microchip registration free?

It depends on the registry. Some charge for registration or updates and some don't, so read the terms before you pay. Registering your pet on LostPet.com is free, but it isn't a microchip registry, so keep your chip registered with a registry too.

How often should I check my pet's microchip?

Check the registration any time you move or change your phone number, and once a year. The AVMA suggests having your vet scan the chip at least yearly, and marks August 15 as Check the Chip Day. Before July 4 and New Year's Eve is a good time too.

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Sources

This guide is general information, not veterinary advice. If your pet is hurt or unwell, contact your veterinarian.