Last updated: April 27, 2026

Microchipping Your Pet: Why It Matters

Every year, millions of pets go missing. They slip through open gates, bolt during thunderstorms, escape during moves, or wander off during outdoor adventures. The difference between a lost pet who comes home and one who does not often comes down to a single thing: permanent identification. Collars and tags are important, but they can fall off, be removed, or become illegible. A microchip cannot be lost, removed, or damaged — it stays with your pet for life.

Despite being available for decades and recommended by virtually every veterinary and animal welfare organization, microchipping remains underutilized. Many pet owners are unsure about how microchips work, whether the procedure hurts, or what happens after the chip is implanted. This guide addresses every question and concern so you can make an informed decision about this simple, affordable step that dramatically increases the chances of being reunited with your pet if they ever go missing.

How Microchips Work

A pet microchip is a tiny electronic device — roughly the size of a grain of rice — enclosed in a biocompatible glass capsule. It does not have a battery, does not emit a signal, and does not track your pet’s location. A microchip is a passive transponder that stores a unique identification number and transmits it only when activated by a microchip scanner held within a few inches of the chip.

When a scanner sends a low-frequency radio signal to the chip, the chip uses the energy from that signal to power itself momentarily and transmit its identification number back to the scanner. This number — typically fifteen digits — is unique to your pet’s chip and is linked to your contact information in a microchip registry database.

The process works like this in practice: a lost pet arrives at a shelter, veterinary clinic, or animal control facility. A staff member scans the pet with a universal microchip scanner. If a chip is detected, the scanner displays the chip’s identification number. The staff member then contacts the microchip registry associated with that number, which provides the owner’s name, phone number, and address. The shelter contacts the owner, and the pet goes home.

It is a simple system, but it is remarkably effective. Studies have shown that microchipped dogs are returned to their owners at more than twice the rate of non-microchipped dogs, and microchipped cats are returned at more than twenty times the rate of non-microchipped cats. The disparity is even more striking for cats because cats are less likely to wear collars and tags than dogs, making microchips their only form of identification in many cases.

The Implantation Procedure

Microchip implantation is one of the quickest, simplest procedures in veterinary medicine. It requires no anesthesia, no surgery, and no recovery time. The entire process takes less than a minute.

How it is done. The microchip comes pre-loaded in a sterile, disposable syringe with a slightly larger-than-normal needle. The veterinarian or veterinary technician inserts the needle under the skin between the pet’s shoulder blades — a standard injection site with loose skin and minimal nerve endings — and depresses the plunger to deposit the chip. The needle is withdrawn, and the procedure is complete.

Does it hurt? The injection is comparable to a routine vaccination — there is a brief pinch as the needle enters the skin, followed by mild pressure as the chip is deposited. Most pets react no more than they would to a standard vaccine. Some do not react at all. The momentary discomfort is equivalent to what your pet experiences during any routine injection, and no pain medication or aftercare is needed.

When to microchip. Pets can be microchipped at any age, but the most common timing is during a puppy or kitten’s early veterinary visits or at the time of spaying or neutering. If your pet is being anesthetized for surgery, the chip can be implanted while they are under anesthesia, eliminating even the brief discomfort of the injection. However, there is no reason to wait for surgery — microchipping can and should be done at the earliest opportunity. If you are adopting a rescue pet, many shelters and rescue organizations microchip animals before they leave the facility. Confirm whether your new pet is already chipped and ensure the registration information is updated to your details.

Cost. Microchipping typically costs between $25 and $75 at a veterinary clinic, and many shelters and animal welfare organizations offer the service for less during special events or as part of adoption packages. This one-time cost provides permanent identification for the life of the pet — there are no batteries to replace, no maintenance required, and no expiration date.

Registration: The Step Most People Miss

Here is the critical point that cannot be emphasized enough: a microchip is only useful if it is registered with your current contact information. An unregistered chip is nothing more than a number with no owner attached to it. A registered chip with outdated information is nearly as useless.

When your pet is microchipped, you will receive paperwork or an online registration prompt with the chip’s identification number and the registry it is associated with. You must complete the registration process by entering your name, address, phone number, email address, and an emergency contact. Some registries charge a one-time or annual fee; others offer free basic registration.

Keep your information current. This is where the system breaks down most often. Pet owners move, change phone numbers, or update email addresses without updating their microchip registration. When a shelter scans a lost pet and pulls up a disconnected phone number, the chip cannot do its job. Update your registration whenever you move, change your phone number, or transfer ownership of the pet. Set a calendar reminder to verify your registration annually.

Register with a universal database. Several microchip registries exist, and not all of them communicate with each other. Registering with a universal lookup service — such as the AAHA Universal Pet Microchip Lookup Tool at petmicrochiplookup.org — ensures that your chip can be found regardless of which scanner or registry a shelter uses. Register with both the chip manufacturer’s database and a universal service for maximum coverage.

Verify the chip after implantation. Ask your veterinarian to scan the chip immediately after implantation to confirm it is reading correctly and displaying the right number. Rare instances of chip migration (the chip moving from the original injection site to a nearby area) or chip failure have been documented. An annual scan during your pet’s regular veterinary checkup takes seconds and confirms the chip is still functional and in an easily scannable location.

Microchips Versus GPS Trackers

A common misconception is that microchips track your pet’s location in real time, like a GPS device. They do not. Understanding the difference between these two technologies helps you decide what combination of identification tools is right for your pet.

Microchips are passive identification devices. They do not emit a signal, require no battery, and cannot be tracked remotely. Their sole function is to provide a permanent identification number that links to your contact information. They work only when a scanner is held within range — typically a few inches. Their advantage is permanence: once implanted, a microchip lasts the life of the pet with no maintenance.

GPS trackers are active devices that attach to your pet’s collar and transmit location data to your smartphone via cellular or satellite networks. They allow you to track your pet’s location in real time, set up geofencing alerts (notification when your pet leaves a designated area), and view movement history. Their limitations are that they require batteries (which need regular charging), they are attached to a collar (which can fall off or be removed), and they rely on cellular coverage (which may be unavailable in rural areas).

The ideal approach is to use both: a microchip as permanent, fail-safe identification that cannot be lost or disabled, and a GPS tracker for real-time monitoring and immediate response if your pet escapes. A collar with an ID tag provides an additional layer — visible identification that any person can read without needing a scanner.

What to Do If Your Pet Goes Missing

If your pet escapes, a microchip gives you the best chance of being reunited, but it works best as part of a broader response plan. Here is what to do immediately.

Confirm your microchip registration is current. If you have not updated your information recently, do so immediately. Contact your microchip registry by phone or online to verify that your current phone number and address are on file.

Contact local shelters and animal control. Call every shelter, animal control office, and veterinary clinic within a reasonable radius of where your pet went missing. Provide your pet’s description and microchip number. Visit shelters in person if possible — visual identification by the owner is more reliable than descriptions relayed over the phone.

Post on social media and lost-pet databases. Share clear photos and your pet’s microchip number on local community groups, neighborhood apps, and dedicated lost-pet websites. Include the microchip number in your posts so that anyone who finds your pet and has them scanned can match the number.

Search the immediate area. Lost dogs often travel farther than lost cats. Dogs may cover several miles in a panic, while cats typically hide close to home — often within a three-to-five-house radius. Search during quiet hours (early morning, late evening) when ambient noise is low and your pet is more likely to respond to your voice. Leave familiar-smelling items — a worn shirt, the pet’s bed — outside your home to help guide them back.

Do not give up. Pets have been reunited with their owners weeks, months, and even years after going missing, often thanks to a microchip that was scanned during a routine veterinary visit or a shelter intake far from home. As long as the chip is registered and your information is current, there is always a chance.

Frequently Asked Questions

Can a microchip cause cancer or other health problems?

The risk is extremely low. Rare cases of tumor formation at microchip implantation sites have been reported, primarily in rodents and a very small number of cats and dogs. The incidence is estimated at fewer than one in a million. Major veterinary organizations — including the AVMA, the World Small Animal Veterinary Association, and the British Small Animal Veterinary Association — have reviewed the data and concluded that the benefits of microchipping far outweigh the minuscule risk of adverse effects. The biocompatible glass casing is designed to be inert and is the same material used in many human medical implants.

Can a microchip be removed?

Surgical removal is theoretically possible but almost never performed. Once implanted, the body forms a thin layer of connective tissue around the chip, anchoring it in place. There is no medical reason to remove a functioning chip, and the surgery required to do so would be more invasive than the original implantation. If a chip malfunctions, a new chip can simply be implanted alongside the old one.

Does my pet need a microchip if they already wear a collar and tags?

Yes. Collars and tags are the first line of identification and are valuable because any person can read them. However, collars can break, slip off, or be removed. Tags can become illegible from wear. A microchip is a permanent backup that remains with your pet even if every external form of identification is lost. The two systems complement each other — neither replaces the other.

Will a microchip work for both dogs and cats?

Yes. The same microchip technology is used for dogs, cats, horses, rabbits, ferrets, and other animals. The implantation procedure is identical for dogs and cats. The only difference is that some cats may be microchipped during their spay or neuter surgery as a matter of convenience, while dogs may be chipped during a routine puppy visit. The chip itself is species-universal.

How do I check if my pet is already microchipped?

Any veterinary clinic, animal shelter, or animal control office can scan your pet for a microchip in seconds at no charge. If a chip is detected, the scanner will display the chip’s identification number, which you can then look up on a universal database like petmicrochiplookup.org to find the associated registry. If you recently adopted a pet, check your adoption paperwork for a microchip number and contact the registry to transfer ownership to your name and contact information.