Does correcting a microchip detail cost anything?

It depends on the type of correction and the region. Updating your own contact details is almost always free, while a change of ownership may carry a small administrative fee. Typos and corrections to the animal's own details are usually free, but rules vary by area: ask your local veterinary service before you turn up, so there are no surprises at the desk.

Can I correct the details online or do I have to go in person?

More and more regions let you update at least the owner's contact details online, often with a digital identity. Corrections that need documentary proof, such as a change of owner, usually still go through the desk or an authorised vet, because someone has to verify the document. Check your region's portal: if the feature exists, it saves you a queue.

The number on the record book does not match what the scanner reads. What do I do?

This is the trickiest case, because you do not know which number the registry holds. Have the vet reread the chip with a reliable scanner, compare the digits read against the registry extract and the record book, and correct whichever document carries the wrong number. If the error is in the registry itself, you need a correction backed by the scanner reading of the chip.

How long before the correction shows up?

For simple contact updates the change is often immediate or takes a few days. Corrections that go through a documentary check can take a few weeks. Either way, do not treat it as done until you have checked a fresh extract: a request submitted and a correction recorded are two different things.

Documents and paperwork40 minLevel: IntermediateUpdated on August 20, 2026

Correcting wrong microchip details in the pet registry

Wrong owner, misspelled name, mixed up species or birth date: how to spot the error, which documents prove the correction and how to confirm it actually went through.

Audience: Pet owners, Breeders
Species: Dog, Cat
Scope: Valid everywhere, Italy, European Union

What you need before you start

Il numero del microchip a 15 cifre, che trovi sul libretto sanitario o sul passaporto europeo
Un documento di identità valido dell'intestatario corretto e il codice fiscale
La documentazione che prova il dato giusto, ad esempio il certificato di cessione o la fattura di adozione
Il recapito del servizio veterinario dell'azienda sanitaria della tua zona

A microchip is not a licence plate that works on its own: it only helps if the number the scanner reads points to an accurate record in the registry. When that record holds an error, an old name, an owner who is no longer the owner, the wrong species, or a birth date invented at first registration, the animal looks protected but is not. The problem stays invisible for years and surfaces at the worst moment: when the animal goes missing, when a shelter reads the chip and calls the wrong person, or when a travel passport is needed and the details do not match. This guide explains how to work out exactly which detail is wrong, how to gather the proof needed to fix it, and how to confirm the correction really went through instead of assuming one phone call was enough.

Recognising that there is an error, and which one

The first step is not to correct, it is to pin down exactly what is wrong. Many owners discover the error by chance, at the vet's desk or as a trip approaches, and in that rush they risk fixing the wrong thing. Before you move, get the extract of the details linked to the chip and compare it line by line against the animal's real documents.

Registered owner: the recorded owner is still the breeder, the shop or the person who handed the animal over, not you.
Name and species: a cat can end up recorded as a dog, or the name can carry a typo.
Sex and birth date: often estimated at the first visit and never corrected, which then affects travel documents.
Contact details: a phone number or address that no longer exists, the most common and most dangerous case.
Chip number itself: rarely, but it happens, the digits written in the record book do not match the implanted chip.

Which document proves which detail

The registry does not change a detail on your word: every correction has to be backed by a document showing what the right information is. Knowing in advance what is needed saves you a second trip. The table pairs the most common error with the proof that usually unlocks it.

Indicative match between type of error and the document that proves the correction. Exact requirements vary by region: confirm them with your local veterinary service before you turn up.
Wrong detail	Document that proves it	Where you get it
Wrong registered owner	Transfer form signed by the previous owner	Whoever handed the animal over, breeder or private
Name or typo	Record book or passport with the correct name	Your vet
Species or sex mixed up	Vet certificate describing the animal	A visit or a written statement from the vet
Mis-estimated birth date	Vet certificate with an updated age estimate	Your vet
Outdated contact details	Photo identity document and proof of address	You, at the desk or online

The procedure step by step

Almost everywhere the correction follows the same shape, whether you do it at the veterinary service desk or through a vet authorised to enter data into the registry. The forms and timelines change, the substance does not.

Get the official extract of the linked details
Ask the veterinary service or your vet for a printout of what the registry currently holds for that chip number. It is the starting point: without seeing the wrong detail in writing you risk correcting an impression rather than a fact.
Identify the authority responsible for that correction
A change of owner almost always goes through the veterinary service, while typos and the animal's own details are often fixed by the vet with registry access. One phone call ahead tells you which door to knock on.
Prepare the proof and your identity document
Bring together the document that shows the right detail, your identity document and your tax code. A change of ownership also needs the signature of whoever handed the animal over.
Submit the correction request
Fill in the indicated form and attach the copies. If the process is online, upload the files in the accepted formats and note the reference number or receipt the system issues.
Record the date and keep the receipt
Note when you submitted the request and to whom. If the detail is still wrong a few weeks later, the receipt is what lets you chase it up without starting over.
Confirm the correction actually went through
After the stated waiting time, ask for a fresh extract and check the detail has changed. A request submitted is not a request completed: until you see it corrected, treat the error as still open.

The special case of a transfer never done

The most common error is not a typo, it is an owner never updated: the animal is still recorded to the breeder, the shop or the person you got it from. This is not a detail, because in many countries the registered owner is also legally responsible for the animal. If the previous owner is reachable, the fix is simple; if not, you need a different route.

Contact whoever handed the animal over and ask for their signature on the transfer form: the fastest and cleanest way.
If they are unreachable, bring the veterinary service every proof of current ownership, such as invoices, vet bills in your name and messages documenting the handover.
If the animal came from a shelter or rescue, ask them for the adoption or fostering document, which is normally enough.
If the previous owner has died, ask about the procedure for animals passing to heirs, which differs from an ordinary transfer.

After the fix: line up everything else

Correcting the registry record is the central step, not the last one. The same wrong detail usually lives in several places, and until you line them all up the error can come back. After the correction, spend ten minutes closing the loop.

Update the record book and passport if they carried the wrong detail, so they match the registry.
Fix the ID tag with the right contact, since it is the first thing a finder reads.
Line up the animal's profile in the app or health diary you use, so all your documents say the same thing.
If you hold an insurance policy, tell the insurer about the change too, as they often require details consistent with the registry.
Keep the correction receipt with the animal's documents as proof of the date the error was fixed.

An identifier is only worth something if it points to whoever truly cares for the animal today, not whoever did yesterday.
Basic principle of pet registration

Frequently asked questions

Does correcting a microchip detail cost anything?: It depends on the type of correction and the region. Updating your own contact details is almost always free, while a change of ownership may carry a small administrative fee. Typos and corrections to the animal's own details are usually free, but rules vary by area: ask your local veterinary service before you turn up, so there are no surprises at the desk.
Can I correct the details online or do I have to go in person?: More and more regions let you update at least the owner's contact details online, often with a digital identity. Corrections that need documentary proof, such as a change of owner, usually still go through the desk or an authorised vet, because someone has to verify the document. Check your region's portal: if the feature exists, it saves you a queue.
The number on the record book does not match what the scanner reads. What do I do?: This is the trickiest case, because you do not know which number the registry holds. Have the vet reread the chip with a reliable scanner, compare the digits read against the registry extract and the record book, and correct whichever document carries the wrong number. If the error is in the registry itself, you need a correction backed by the scanner reading of the chip.
How long before the correction shows up?: For simple contact updates the change is often immediate or takes a few days. Corrections that go through a documentary check can take a few weeks. Either way, do not treat it as done until you have checked a fresh extract: a request submitted and a correction recorded are two different things.

What to do next

Start from an official data extract to see exactly which detail is wrong, then pair each error with the document that proves it and submit the correction to the right authority, in person or online. Note the receipt, confirm on a fresh extract that the change really went through, and line up the record book, tag, app and insurance, so the same error does not reappear when you need the chip most.