When someone imports a car, it is common to hear two different requests: provide the vehicle registration certificate and provide its Certificate of Conformity (COC). Because both documents contain technical details and identify the same vehicle, they are often confused.
They serve different purposes. Understanding the distinction is important when buying a vehicle abroad, preparing a registration application or asking for a missing document to be replaced.
What is the registration certificate?
A vehicle registration certificate is the official document issued by the authority that registered the vehicle. Depending on the country, it may be known as a registration document, Zulassungsbescheinigung, carte grise or permiso de circulación.
It records information used for the vehicle’s administrative registration, such as its registration number, identifying details, registration dates and the registered keeper. Some countries issue the certificate in two parts. When re-registering a vehicle in another EU country, you may need to present both original parts.
The registration certificate is not always conclusive proof of legal ownership. A purchase invoice or signed sales agreement may also be needed.
What is a Certificate of Conformity?
A COC is issued by the vehicle manufacturer under the relevant type-approval framework. Rather than documenting where the car is registered, it describes how an individual vehicle corresponds to an approved type and records approved technical characteristics.
The information can include the manufacturer’s designation, variant and version, engine or propulsion data, dimensions, masses, emissions values, tyres and an EU type-approval reference.
A COC is particularly useful when registration authorities need to establish technical details that may not appear, or may not appear in sufficient detail, on the existing national registration document.
Key differences at a glance
| Question | Registration certificate | Certificate of Conformity |
|---|---|---|
| Who issues it? | National registration authority | Vehicle manufacturer |
| Main purpose | Records official vehicle registration | Declares conformity with the approved vehicle type |
| What does it focus on? | Administrative registration and keeper data | Approved technical and type-approval data |
| Does it replace the other? | Generally no | Generally no |
| Can another country request it? | Yes, often the original | Yes, depending on the procedure |
Why can you be asked for both documents?
Imagine a used car purchased in Germany for registration in Spain. Its German registration documents tell the Spanish authorities about its previous registration. A European COC can provide the technical approval information needed to prepare the Spanish ITV documentation.
The receiving authority may also require the sale contract, evidence of taxes and a roadworthiness check. Supplying one correct certificate does not eliminate these unrelated obligations.
What if the registration document is missing?
A missing registration certificate must normally be addressed through the relevant registration authority and its established replacement or export process. Buying a COC will not recreate a missing registration record.
If the registration certificate is present but the COC is missing, the next step may be to request an official manufacturer-issued duplicate, provided the vehicle is eligible. In some countries, specific alternative technical reports may also be acceptable.
The two problems have different solutions, so identify exactly which document the authority is requesting before spending money.
Do digital versions change this distinction?
No. Digital formats do not make the documents equivalent. EU legislation now provides for structured electronic conformity data under defined conditions, while national registration systems continue to have their own procedures for receiving and checking documents.
A registration authority may accept a digital COC in certain situations, but that does not mean it will accept a photograph of a registration card or an unauthorised copy of an official document.
Order the right document for your vehicle
If your registration office specifically requests a manufacturer Certificate of Conformity, first check that the vehicle qualifies and confirm the accepted format. COC Market’s online catalogue lets you explore available manufacturer options.
Remember: registration documents tell authorities about the vehicle’s registration history; a COC tells them about its approved technical configuration. They often work together during a cross-border registration.
Official sources and further reading
Information reviewed October 2026. Regulations, authority procedures and document acceptance can change; confirm the latest local requirements before applying.
