Registration in Bulgaria’s Central Professional Register of Builders (CPRB) — Categories, Groups and Procedure (2026)

Legal Framework

Registration in the CPRB is governed by several interconnected legal acts that together form the regulatory framework for the construction industry in Bulgaria:

• Construction Chamber Act (ZKS) — promulgated in State Gazette No. 108/2006, the ZKS establishes the Bulgarian Construction Chamber (KSB), governs the maintenance of the CPRB and sets out the conditions for registration. Article 3 ZKS explicitly provides that construction of buildings from first to fifth category, or the performance of specific types of construction and assembly works (CMR), may only be carried out by builders registered in the CPRB.
• Regulation on the Procedure for Registration and Maintenance of the CPRB — this secondary legislation details the registration procedure, required documents, standard forms and deadlines. The Regulation also defines the groups of construction works in which builders may apply for registration.
• Spatial Planning Act (ZUT) — Article 137 ZUT introduces the classification of construction works into five categories based on their complexity, significance and risk characteristics. This categorisation is directly linked to the CPRB registration requirements.

The competent authority for registration is the Commission for the Maintenance, Administration and Use of the CPRB within the Bulgarian Construction Chamber. KSB is a professional organisation of builders headquartered in Sofia with regional chapters throughout the country.

Who Must Register in the CPRB

The obligation to register in the CPRB applies to any person intending to carry out construction activities on the territory of Bulgaria. More specifically, registration is mandatory for:

• Builders (legal entities) that carry out construction works classified in categories one through five under ZUT — including new construction, reconstructions, major renovations and conversions.
• Builders performing specific types of construction and assembly works (CMR) — even when not executing an entire construction project but only a specific type of work (formwork, reinforcement, concrete, assembly, finishing works, etc.), registration is mandatory.
• EU/EEA builders — builders established in another EU or EEA member state may carry out activities in Bulgaria under certain conditions (see the section on EU/EEA builders).

Carrying out construction without CPRB registration constitutes an administrative offence punishable by fines, and the construction site may be ordered to stop. Contracting parties (investors) are also obliged to verify the builder's CPRB registration before entering into a contract.

A builder may apply for registration in one or more categories and one or more groups of construction works simultaneously, depending on their capacity, qualifications and experience.

Five Categories of Construction under ZUT

Article 137 of the Spatial Planning Act classifies construction works into five categories, ranked from the most complex and high-risk to the simplest. The category of a construction project determines the level of requirements for the builder:

A builder registered for a higher category may also carry out construction works of any lower category. The reverse is not permitted — a builder registered for the fourth category cannot execute third-category or higher projects.

Groups of Construction Works and Specific Types of CMR

In addition to categories, construction works are classified into groups under the Regulation on Registration and Maintenance of the CPRB. The groups reflect the specialisation of the construction activity:

• Group 1: Building construction — residential, public and industrial buildings, conversions and reconstructions of existing buildings. This is the most common group, covering the bulk of construction activity in the country.
• Group 2: Transport infrastructure — roads, motorways, railway lines, bridges, tunnels, road structures, airport runways and port infrastructure.
• Group 3: Energy infrastructure — hydroelectric power plants, thermal power plants, photovoltaic and wind farms, substations, power lines and gas pipelines.
• Group 4: Water supply and sewerage (WSS) infrastructure — water supply and sewerage networks, wastewater treatment plants, dams, pumping stations and reservoirs.
• Group 5: Public amenities infrastructure — streets, squares, parks, gardens, playgrounds, outdoor sports facilities and street lighting.

Specific Types of Construction and Assembly Works

Builders may also apply for registration to perform specific types of construction and assembly works (CMR) without necessarily executing an entire project. The most common types include:

• Formwork
• Reinforcement
• Concrete works
• Assembly works (steel structures, installations)
• Masonry and plastering
• Finishing works (painting, flooring, cladding)
• Insulation works (waterproofing, thermal, acoustic)
• Road and earthworks

A builder may combine category and group registrations depending on the scope of their business. For example, a company specialising in residential construction would typically apply for Group 1, third or fourth category.

Requirements for CPRB Registration

To be registered in the Central Professional Register of Builders, the applicant must satisfy a comprehensive set of requirements that demonstrate professional competence:

1. Legal Status

• Registration in the Commercial Register with the Registry Agency (or an equivalent register in the country of establishment for EEA builders).
• The company must not be in insolvency or liquidation proceedings.

2. Qualified Personnel

The minimum requirements for the technical site manager depend on the category applied for:

Personnel must be engaged under an employment or civil contract and must be included in the standard-form personnel and qualifications report.

3. Technical Equipment

The builder must have access to the necessary construction machinery and equipment — whether owned or leased. The technical equipment report is prepared using a standard form and includes a description of the available machinery, its condition and the legal basis for use (ownership, leasing, rental).

4. References for Completed Projects

The builder must provide evidence of successfully completed construction projects corresponding to the category and group applied for. References demonstrate the company's practical experience and capacity.

5. Occupational Health and Safety (OHS)

A documented occupational health and safety system is required, including:

• Workplace risk assessment
• Worker briefings (initial, on-the-job, periodic)
• Personal protective equipment
• Designated OHS officer or contract with an Occupational Health Service

6. Qualification Training

The builder must submit a report on qualification training provided to personnel. KSB places emphasis on continuous professional development and upskilling of construction workers.

7. Specialised Licences and Certificates

For construction activities with elevated risk (work with explosives, gas installation, work at height, etc.), additional licences and certificates issued by the competent authorities are required.

Required Documents for Registration

The application for registration in the CPRB is submitted to the CPRB Commission and must be accompanied by the following documents:

1. Application form — a standard form approved by KSB, specifying the requested category/categories and group/groups of construction works.
2. Commercial Register certificate — a current extract confirming the legal status of the company (KSB may verify this ex officio using the company's UIC).
3. Declaration of non-insolvency — a standard-form declaration that the company is not subject to insolvency or liquidation proceedings.
4. Licences and certificates for specialised activities — where applicable for activities involving elevated risk or special requirements.
5. Personnel and qualifications report — using the KSB standard form, containing data on the education, qualifications and professional experience of technical staff.
6. Qualification training report — information on training courses completed by personnel in recent years.
7. Technical equipment report — using the standard form, describing available construction machinery and equipment.
8. References for completed projects — a list of completed construction projects specifying category, group, client and period of execution.
9. Proof of payment of fees — bank transfer receipt for the KSB membership admission fee and the CPRB registration fee.

Standard forms for reports and the application are available on the KSB website. If the submitted documents are incomplete, the Commission notifies the applicant and sets a deadline for rectification.

CPRB Registration Fees

Fees for KSB membership and CPRB registration are determined annually by the General Assembly of the Bulgarian Construction Chamber. Indicative amounts for 2026 are:

Important: Exact amounts are determined by the KSB General Assembly and may vary depending on the categories and groups applied for. The registration fee for first and second categories is higher than for fourth and fifth. Payment is made exclusively by bank transfer. We recommend checking the current fees on the KSB website before submitting your application.

Registration Procedure

The CPRB registration procedure involves several sequential stages:

1. Preparation of documentation — the builder gathers and prepares all required documents, completes the standard-form reports and pays the applicable fees.
2. Submission of the application — the application and accompanying documents are submitted to the CPRB Commission. Registration can now be completed entirely electronically, which significantly streamlines the process.
3. Review by the CPRB Commission — the Commission examines the submitted documents and verifies whether the applicant meets the requirements for the requested category and group. If deficiencies are identified, a deadline for rectification is set.
4. Decision on registration — the Commission issues its decision within 1 to 2 months of submission of the complete document package. Upon approval, the builder receives a certificate of registration.
5. Publication in the register — the registration is publicly accessible on the electronic register at register.ksb.bg. Contracting parties and regulatory authorities can verify the status of any builder in real time.

In case of refusal, the builder may appeal the decision under the Administrative Procedure Code. In practice, refusals most commonly result from incomplete documentation or non-compliance of personnel qualifications with the requirements for the requested category.

Ongoing Obligations after Registration

Registration in the CPRB is not a one-time act — it creates a number of ongoing obligations, failure to comply with which may result in deletion from the register:

• Annual maintenance fee — the builder pays an annual fee to maintain their CPRB registration. Failure to pay within the specified deadline may result in ex officio deletion.
• Annual update of reports — the personnel and technical equipment reports must be updated annually. The builder is required to submit current data on staff numbers and qualifications, as well as available equipment.
• Mandatory qualification training — KSB requires continuous professional development of construction workers. The builder must ensure and document the delivery of training programmes.
• Notification of changes in circumstances — when changes occur in the circumstances subject to registration (change of manager, change of address, changes in personnel, etc.), the builder must notify the CPRB Commission within 14 days.
• Maintenance of the OHS system — the occupational health and safety system must operate continuously, and its documentation must be regularly updated.

EU/EEA Builders

Builders established in another EU or EEA member state may carry out construction activities in Bulgaria in two ways:

Temporary or One-Off Provision of Services

An EU/EEA builder may carry out construction activities in Bulgaria without CPRB registration when providing services on a temporary or one-off basis. In this case, the builder submits a declaration to KSB, accompanied by:

• Certificate of establishment in the home member state
• Evidence of professional qualifications
• Professional liability insurance policy

Permanent Establishment and CPRB Registration

Where an EU/EEA builder intends to carry out construction activities in Bulgaria on a permanent basis, standard CPRB registration is required. Documents issued in another member state are recognised, provided they are legalised or apostilled (where applicable) and translated into Bulgarian.

The Bulgarian Construction Chamber cooperates with the competent authorities of other member states to verify the submitted documents and qualifications through the Internal Market Information System (IMI).

Sanctions for Non-Compliance

The legislation provides for serious consequences for violations of CPRB registration requirements:

• Construction without CPRB registration — carrying out construction activities by an unregistered builder is punishable by administrative fines. Regulatory authorities (DNSK, municipalities) may order the construction site to be stopped until the violation is rectified.
• Provision of false information — if it is established that the builder submitted false data during registration (fabricated personnel reports, non-existent equipment, fictitious references), the Commission may delete the registration from the register.
• Systematic violations — in cases of repeated or systematic violations of construction regulations, OHS rules or ZKS obligations, the Commission may impose temporary or permanent deletion from the CPRB.
• Failure to comply with ongoing obligations — non-payment of the annual fee, failure to submit updated reports or failure to notify changes in circumstances may also result in deletion.

Deletion from the CPRB means an immediate prohibition on carrying out construction activities. Reinstatement requires a new application and completion of the registration procedure from scratch.

Frequently Asked Questions