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Part of our CDM 2015 series. See CDM Regulations 2015 explained for every duty holder and key document in one place.
Under CDM 2015, a contractor is anyone who carries out, manages or controls construction work as part of a business. That covers main contractors, subcontractors, specialist trades and self-employed tradespeople. If you employ or manage people doing construction work, or do it yourself for a business, you are a contractor.
Every contractor duty at a glance
| Duty | What it means in practice |
|---|---|
| Check the client knows their duties | Do not carry out work unless satisfied the client is aware of its CDM duties. |
| Plan, manage and monitor your work | Make sure your work is carried out without risks to health and safety, so far as is reasonably practicable, usually through RAMS. |
| Follow the principal contractor’s directions | Where there is more than one contractor, comply with the principal contractor’s directions and the construction phase plan. |
| Employ competent people | Only employ or appoint people who have, or are gaining, the skills, knowledge, training and experience for the work. |
| Provide supervision, instruction and information | Give every worker appropriate supervision and the information they need, including a site induction, emergency procedures and information on the risks. |
| Prevent unauthorised access | Take reasonable steps to stop unauthorised people entering the site. |
| Provide welfare for your workers | Make sure welfare facilities are available, as set out in Schedule 2. |
| Comply with Part 4 | Meet the general site requirements in Part 4, such as safe places of work, excavations, traffic routes and fire precautions, for work under your control. |
| Cooperate and report | Cooperate with others and report anything likely to endanger anyone. |
Single contractor projects
Where you are the only contractor, there is no principal contractor, so you take on extra responsibility. You must draw up a construction phase plan before setting up the site, proportionate to the job. On a domestic project, the client’s duties also pass to you.
Self-employed contractors
Self-employed people who carry out construction work are contractors under CDM. They have the same duties for the work under their control, and must also cooperate with the principal contractor and follow the site rules.
What a contractor should have ready
- RAMS for each task, specific to the site
- Training and competence records, including cards and certificates
- Inspection records for plant, tools, scaffolds and excavations under your control
- Induction and toolbox talk records
- A plan for supervision, including who is in charge each day
Training that helps
Contractors usually need site managers with SMSTS and supervisors with SSSTS. For a broader management qualification, the NEBOSH Health and Safety Management for Construction certificate covers CDM in depth. Our CDM awareness eLearning and managing contractors eLearning are quick online options for wider teams.
Where this fits in SMSTS and SSSTS
Contractor duties and supervising work safely are central to both courses. Our free SMSTS mock test and SSSTS mock test let you check your knowledge before the course or a refresher, and you can email yourself the results sheet at the end.
When you are ready, the five day SMSTS course is for site managers and the two day SSSTS course is for supervisors. If your certificate is due, the SMSTS refresher and SSSTS refresher keep it current.
Frequently asked questions
Is a subcontractor a contractor under CDM?
Yes. Any business that carries out, manages or controls construction work is a contractor, including subcontractors and the self-employed.
Does a single contractor need a construction phase plan?
Yes. Where there is only one contractor, that contractor must draw up a proportionate construction phase plan before setting up the site.
Who provides welfare on a site with several contractors?
The principal contractor must make sure welfare is provided, and each contractor must make sure facilities are available to its own workers.
Do contractors have to induct their workers?
Yes. Every worker must have a suitable site induction, provided by the principal contractor or, on single contractor jobs, by the contractor.
Read the source
The Construction (Design and Management) Regulations 2015, regulations 7, 8 and 15, Part 4 and Schedule 2; and HSE guidance L153, Managing health and safety in construction. Facts checked on 6 October 2026.
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