The client is not an idle participant in a CDM 2015 project. The regulations place direct legal obligations on clients — not just on the contractors doing the work. On many projects these obligations are delegated in practice to the principal designer or principal contractor, but the legal responsibility stays with the client.
This matters for commercial clients who commission construction work but are not themselves in the construction industry. A property developer, a retailer, a school, a local authority — all are "clients" under CDM 2015 and all carry these duties on any project involving construction work.
Who counts as a client under CDM 2015?
A client is an organisation or individual for whom a construction project is carried out (Regulation 2(1)). The client does not need to be in the construction industry. If you commission construction work — even indirectly, through a management contractor — you are a client.
CDM 2015 distinguishes between commercial clients (organisations or individuals for whom the project is in connection with a business, whether or not for profit) and domestic clients (those having work carried out on their own home that is not in connection with any business). Commercial client duties are broader than domestic client duties.
Where a project has multiple clients (a developer and a future tenant co-commissioning a fit-out, for example), Regulation 4(8) allows them to designate one of them to carry the client duties, by written agreement.
The core management duty
Regulation 4(1) establishes the foundation of the client's CDM obligation:
"A client must make suitable arrangements for managing a project, including the allocation of sufficient time and other resources."
"Suitable arrangements" must ensure:
- The construction work can be carried out, so far as is reasonably practicable, without risks to health or safety
- Welfare facilities are provided as required by Schedule 2 of CDM 2015
This duty continues throughout the project. A client who makes the appointments and then disengages has not fulfilled the management duty — the regulations require ongoing oversight to ensure arrangements remain suitable as the project develops (Regulation 4(3)).
Appointment duties
Appointing a principal designer
On any project involving more than one contractor, the client must appoint a principal designer in writing (Regulation 5(1)(a)). The principal designer must have "the skills, knowledge and experience, and, if they are an organisation, the organisational capability, necessary to fulfil the role" (Regulation 8(1)).
The appointment must be made as soon as is practicable, and in any event before the construction phase begins (Regulation 5(2)). In practice it should be made before design work begins in earnest, not at tender stage — a late appointment means the principal designer missed most of the design risk coordination opportunity.
If the client does not make the appointment, or if the appointment lapses and is not replaced, the client assumes the principal designer duties themselves (Regulation 5(3)). Very few clients are positioned to fulfil those duties — which is why the appointment obligation matters.
For a full explanation of what the principal designer does, see the principal designer's duties under CDM 2015.
Appointing a principal contractor
On any project involving more than one contractor, the client must also appoint a principal contractor in writing (Regulation 5(1)(b)). Again, the appointee must have the skills, knowledge, experience, and (for an organisation) organisational capability required for the role (Regulation 8(1)).
The principal contractor appointment must be made before the construction phase begins (Regulation 5(2)). If the client fails to make this appointment, the client assumes the principal contractor duties (Regulation 5(4)).
Both appointments must be reviewed and updated by the client if the arrangement changes — if a principal contractor is replaced, for example, the client must appoint the replacement formally, not simply accept a novation between contractors.
Pre-construction information
Regulation 4(4) requires the client to provide pre-construction information to every designer and contractor appointed — or being considered for appointment — as soon as is practicable.
Pre-construction information is the information the client holds or can reasonably obtain about the site: ground conditions, existing services, the presence of asbestos, previous site uses, the location of underground utilities, structural drawings of existing buildings, and any other information relevant to the health and safety of those who will design or build the project.
The purpose is to ensure designers and contractors can make informed decisions about risk. A structural engineer designing a foundation without knowing the ground conditions is working blind. A demolition contractor who discovers asbestos that should have been declared in pre-construction information is in a dangerous and avoidable position.
The client does not need to commission surveys it did not have before — but must use reasonable endeavours to gather relevant information and provide it. In practice this means commissioning a ground investigation if none exists and the project warrants it, obtaining existing utility drawings from network operators, and making available any existing structural records or surveys of the site or existing buildings.
See our guide to pre-construction information under CDM 2015 for a full breakdown of what this package should contain.
Notification duty (notifiable projects)
On notifiable projects — those expected to last more than 30 working days with more than 20 simultaneous workers, OR to exceed 500 person-days — the client must notify HSE before the construction phase begins (Regulation 6).
This notification is the F10. The client is responsible for ensuring the F10 is submitted, though the principal designer or principal contractor typically prepares it on the client's behalf. The client must sign the declaration in the F10 confirming they are aware of their CDM duties.
For everything you need to know about F10 notification — thresholds, what to include, and how to submit — see our guide to CDM F10 notifications.
Construction phase plan and health and safety file
The client must ensure that:
- A construction phase plan is prepared by the principal contractor before the construction phase begins (Regulation 4(5)(a)) — and that the plan complies with the requirements of Regulation 12
- The principal designer prepares a health and safety file for the project (Regulation 4(5)(b))
The client does not write either document. But the client is responsible for ensuring they exist and that they are adequate before the relevant phase begins. On a project where the construction phase begins with no construction phase plan in place, the client has failed this duty.
At project completion, the health and safety file must be passed to the client (Regulation 12(10)). The client must then:
- Keep the file and make it available for inspection by anyone who needs it for future maintenance or construction work on the structure (Regulation 4(6))
- Update the file as necessary when further construction work is carried out on the structure
- If the client disposes of their interest in the structure, provide the file to the person who acquires that interest and ensure they are aware of its nature and purpose (Regulation 4(7))
The health and safety file is a long-term asset, not end-of-project paperwork to file away. It informs everyone who carries out future work on the building — surveyors, future contractors, fit-out teams — about residual risks from the original construction. For more detail, see our guide to the CDM health and safety file.
Ongoing oversight
The client's CDM obligations do not end with appointments and information provision. Regulation 4(3) requires the client to "maintain and review the management arrangements" throughout the project. In practice this means:
- Confirming the principal designer and principal contractor are carrying out their roles
- Receiving and reviewing the construction phase plan before work starts (or ensuring a competent person reviews it on the client's behalf)
- Taking reasonable steps to ensure the principal designer and principal contractor are cooperating with each other
- Acting promptly if problems are identified — if the principal designer is not attending design meetings, or the construction phase plan is inadequate, the client cannot simply assume someone else will fix it
Can the client take on duty holder roles?
Where the client fails to appoint a principal contractor, Regulation 5(4) provides that the client must fulfil the duties of the principal contractor. In practice, a client who is also a contractor may choose not to appoint a separate principal contractor — meaning they take on those duties directly. This is rare for commercial clients but does arise on complex procurement arrangements where a developer is also acting as principal contractor on their own project.
It is also possible on a single-contractor project for the contractor to take on both contractor and (limited) coordinating functions without a separate principal designer appointment — because a separate principal designer is only required when more than one contractor is involved.
What happens if the client does not fulfil these duties?
Failure to comply with CDM 2015 client duties is a breach of statutory duty, enforceable by HSE. HSE can issue improvement notices, prohibition notices, and prosecute. Unlimited fines and, for serious breaches, imprisonment are possible outcomes.
On larger projects, a client who fails to appoint a principal designer or principal contractor, fails to provide pre-construction information, or fails to notify an F10 on a notifiable project is carrying a significant compliance risk — and may be contributing to site conditions that lead to accidents for which the client bears partial liability.
Sources
- The Construction (Design and Management) Regulations 2015 (SI 2015/51), Regulations 2, 4, 5, 6
- HSE — CDM 2015 guidance
- HSE L153 — Managing health and safety in construction
This guide is for informational purposes and does not constitute legal advice. For project-specific CDM compliance questions, consult a qualified health and safety professional.
Last reviewed: 22 July 2026