Cartest is an accredited testing laboratory (PCA accreditation certificate: AB 1607) and a technical service authorised by the Director of the Transport Technical Supervision. We test category M, N and special-purpose vehicles in which design changes have been made that alter the vehicle type or purpose or the number of seating positions, and we issue confirmation that the technical requirements needed for registration are met.
Are you planning to rebuild a car, change the number of seats or adapt a vehicle to carry persons with disabilities in wheelchairs? Contact us.
Want to commission confirmation of design changes?
What are vehicle design changes?
Design changes are modifications to the construction of a registered vehicle that affect its technical parameters and require the data in the registration certificate to be updated. Depending on the scope of the conversion they may change the vehicle type (e.g. from goods to passenger), its purpose or the number of seating positions.
Changes of a smaller scope are confirmed by an additional technical inspection at a vehicle inspection station. Where the changes alter the vehicle type or the number of seats, the correct fitting of the new elements must be confirmed by a technical service designated by the Director of TDT. That is where Cartest testing services come in. On the basis of that confirmation a diagnostician carries out a technical inspection of the vehicle at a vehicle inspection station (SKP).
Which design changes require confirmation by a technical service?
Confirmation by a technical service is required for design changes that alter the vehicle type, its purpose or the number of seating positions. These are the changes listed in §§ 9a-9j of the Regulation of the Minister of Infrastructure on the technical conditions of vehicles and the scope of their necessary equipment.
| Provision | Kind of design change |
|---|---|
| § 9a | Increase in the number of seating positions or conversion of a passenger or special car (body type AB, AC, AF) into a goods vehicle |
| § 9b | Increase in the number of seating positions in a goods vehicle (N1, N2) |
| § 9c | Reduction in the number of seating positions in a goods vehicle (N1) |
| § 9d | Conversion of a goods vehicle (N1, N2) into a bus by increasing the number of seating positions |
| § 9f | Conversion of a goods vehicle (N1) into a passenger or special car where the number of seats is increased |
| § 9g | Increase in the number of seating positions in a bus |
| § 9h | Adaptation of a vehicle (M1, N1, N2) to carry persons with disabilities in wheelchairs |
| § 9j | Increase in the number of seating positions in a passenger or special car (body type BB, up to 7.5 t) |
The technical service verifies that the system fitted in the vehicle matches the design of the solution and the tests carried out by the manufacturer. Under § 9i, confirmation issued by the technical service (for §§ 9a, 9b, 9d, 9f, 9g and 9j) may be replaced by a statement of the base vehicle manufacturer or its authorised representative confirming that the design changes do not affect the conditions checked in the production process of that vehicle.
Legal basis for design changes
Confirmation that the relevant technical conditions or requirements are met for vehicles in which design changes have been made is based on the Road Traffic Act, Article 66(4b). The kinds of changes and the requirements are set out in the regulation of the Minister of Infrastructure on the technical conditions of vehicles.
Who may carry out design changes to a vehicle?
Design changes that alter the vehicle type are in principle prohibited — that is what Article 66(4)(6) of the Road Traffic Act says. There are two exceptions: a vehicle of a type for which a type-approval certificate has been issued (lit. a), and a vehicle in which the design changes were made by an entrepreneur conducting business in that field (lit. b). In practice this means one thing: a conversion that changes the vehicle type may legally be carried out only by an authorised entrepreneur, not by the owner in their own garage.
The conversion itself — fitting, removal, adaptation — is therefore done by a company conducting vehicle repair and maintenance (PKD code 45.20.Z), entered in the register of economic activity (CEIDG). After the work it issues the owner a statement of the scope of the changes.
Where to obtain confirmation of vehicle design changes?
Confirmation that the relevant technical conditions or requirements under §§ 9a–9j are met can be obtained from an authorised technical service or from the Director of TDT. After confirmation, an authorised diagnostician at a vehicle inspection station carries out a technical inspection, which is the basis for changes in the registration certificate.
How does confirmation of design changes work at Cartest?
The process is divided into several stages — from conversion, through tests at the technical service, to notification at the vehicle registration office.
- Conversion. An authorised entrepreneur carries it out and issues a statement confirming that design changes have been made and describing their scope.
- Application. You contact Cartest; we agree the scope of tests and accept the application for confirmation.
- Tests. We check whether the vehicle after the changes meets the requirements of the relevant UNECE regulations — including seat mounting and safety-belt anchorages.
- Confirmation. After a positive result we issue a document confirming that the requirements are met.
- Technical inspection. The vehicle inspection station carries out a technical inspection on the basis of the confirmation we issued.
- Registration. After obtaining the certificate from the inspection station you report the changes at the vehicle registration office, where the data are updated and a new registration certificate is issued.
What documents are needed for design changes?
The set depends on the kind of change and the stage. Below we set out information on documents needed at the vehicle registration office. When design changes have been made, registration of them usually requires the following documents:
- the vehicle registration certificate,
- a statement or certificate of the entrepreneur who carried out the design change (sometimes also a current extract from the National Court Register or an entry in the register of economic activity of that company),
- invoices or receipts for parts and labour,
- confirmation that technical requirements are met from an authorised technical service (for changes under §§ 9a-9j) and a certificate from an additional technical inspection at a vehicle inspection station confirming that the changes comply with the rules; a valid, current periodic vehicle inspection also helps,
- an application for a replacement registration certificate and the owner’s identity document.
The change must be reported at the vehicle registration office within 30 days. Before the visit, check the list at your district office — it can differ in the details, and other documents apply for example when data are changed after the registration certificate is lost.
How much does confirmation of design changes cost?
The total cost comprises several items: tests at the technical service or an inspection at a vehicle inspection station, and official fees for updating the data. We set the cost of tests at Cartest individually — it depends on the kind of change, the vehicle category and the scope of trials.
| Item | Cost |
|---|---|
| Tests and confirmation that technical requirements are met at Cartest (changes under §§ 9a-9j) | individual quote |
| Additional technical inspection at an SKP after design changes | PLN 125 |
| Additional inspection together with a periodic technical inspection (when the vehicle has no valid inspection) | PLN 274 |
| Issue of a new registration certificate | approx. PLN 54 |
| Stamp duty for a power of attorney | PLN 17 |
The inspection-station fees follow from the regulation and apply from the September 2025 update — a periodic technical inspection of a passenger car now costs PLN 149. The inspection after a design change costs PLN 125, so the total inspection cost if there is no current periodic inspection is PLN 274. We will prepare an individual quote for tests at Cartest after agreeing the details.
Want to confirm design changes? Contact Cartest
Do you have a question about vehicle design changes, the scope of tests or the required documents?
Write to cartest@cartest.pl or call +48 605 335 804.
We will help you choose the scope of tests and complete the formalities. We will make sure that after conversion your vehicle is safe and compliant.