Contractor compliance requirements in the UK come down to a stack of numbers, cards and badges that clients check before they let you on their books: your CIS status, your UTR, your insurance, your trade registrations and, for bigger buyers, a health and safety accreditation. You do not need all of them. You need the ones your clients ask for, in the right order.
People waste money on badges nobody asked for, then miss the free number that would have got them through the door.
This page is the index. One short entry per term, how many work sources ask for it, and a link to the full guide where one exists. We add links as new guides go live.
How many UK work sources actually ask for each one
We went through what 557 UK work sources ask for at registration. Housing associations, councils, tier-1 contractors, insurance repair networks, FM companies, commercial landlords, utilities, agencies and trade platforms.
Every number below is a floor, phrased as "at least N of the 557 UK work sources we tracked as of July 2026". Floor, because plenty of portals only show their full list once you're inside.
The shape is simple. The free numbers (CIS, UTR, VAT) and the insurance show up everywhere. Trade registrations like Gas Safe cluster around repairs and maintenance buyers. Accreditations like CHAS and Constructionline get heavier the bigger the client.
Which ones do you actually need
Here's how I'd sort it by the business you run today.
| Item | Sole trader, no staff | Ltd or anyone with employees | When you do NOT need it |
|---|---|---|---|
| CIS registration and UTR | Yes, if you do construction work for contractors | Yes | You only work direct for homeowners |
| Public liability | Yes, nearly every client asks | Yes | Rarely skippable once you work for businesses |
| Employers' liability | Usually not, unless you take on labour-only help | Yes, it's a legal requirement with employees | Genuine sole trader, no staff, no labour-only subbies |
| Gas Safe, NICEIC or NAPIT | Only for gas or notifiable electrical work | Same, per trade | Any other trade |
| CSCS card | When you work on managed sites | Same, per operative | Domestic repairs and most reactive maintenance |
| SSIP scheme (CHAS and others) | Only when a target client demands one | Usually, once you chase HAs and tier-1s | Homeowners, small landlords, letting agents |
| ISO 9001, modern slavery statement | Rarely | When bidding for bigger contracts | Most small trade work |
Notice the last column. Nobody selling accreditation writes that one.
The A-Z of contractor compliance
CIS (Construction Industry Scheme)
HMRC's scheme for payments between contractors and subcontractors. Registered subbies have 20% deducted, unregistered 30%, gross payment status 0%. Registration is free. At least 77 of the 557 capture your CIS status at sign-up. Full guide: What Is CIS?
CSCS card
The site card that proves you passed the CITB health, safety and environment test and hold the right qualification for your role. Not a legal requirement, but managed sites will turn you away without one. At least 13 of the 557 state it as a requirement. Full guide: CSCS cards, types and costs
Constructionline
A pre-qualification database big buyers use to filter suppliers, with tiers from Bronze up. At least 101 of the 557 name it somewhere, often as a form field rather than a hard gate.
DBS check
A criminal record check. Anyone can get a basic one. Standard and enhanced checks are only for roles the law makes eligible, so think schools and care settings. At least 18 of the 557 ask about it.
Employers' liability insurance
Legally required once you employ people, with a minimum of £5 million cover. Labour-only subbies can count as employees for this. At least 57 of the 557 name it in onboarding. Full guide: Employers' liability, when you legally need it
Gas Safe registration
The legal register for anyone doing gas work for payment. At least 102 of the 557 capture it, the highest count on this page. Full guide: What Is Gas Safe Registration?
Gross payment status
The CIS status that stops deductions entirely. HMRC wants £30,000 of construction turnover a year per sole trader, partner or director, or £100,000 for a partnership or company as a whole, plus a clean compliance record. Figures checked on GOV.UK on 10 October 2026. Where it pays off: CIS work and getting paid gross
ISO 9001
A certified quality management system. It matters for larger contracts and frameworks, far less for reactive repairs. At least 60 of the 557 mention an ISO standard.
MCS certification
The standard for installers of heat pumps, solar and other small-scale renewables. Customers usually need an MCS installer to claim government incentives. At least 25 of the 557 ask for it.
Modern slavery statement
A published annual statement is a legal duty only at £36 million turnover and above. Below that, some buyers still ask what your policy is. At least 33 of the 557 raise it. Have a one-page policy ready.
NICEIC and NAPIT
Competent person schemes that let electricians self-certify notifiable electrical work. If you do electrical installation, clients expect one of them. At least 33 of the 557 name them.
PAS 2030 and PAS 2035
The standards behind government-funded retrofit work, run through TrustMark. Check the current edition, the 2023 versions are replacing 2019. At least 19 of the 557 ask for it.
Public liability insurance
Covers injury or damage you cause to third parties. Not a legal requirement, but usually the first document clients ask for. At least 25 of the 557 explicitly ask for it in what they publish, and far more capture it on the form. Full guide: Public liability for contractors, explained
RAMS
Risk assessment and method statement. Risk assessment is a legal duty for employers; the method statement is what sites and clients expect alongside it, job by job. At least 23 of the 557 ask for them.
SSIP schemes (CHAS, SafeContractor, SMAS, Acclaim)
SSIP is the umbrella that lets one health and safety assessment be recognised by other member schemes, so you should only need one. At least 123 of the 557 name an SSIP scheme or Constructionline. CHAS lists Standard from £429 a year, Advanced from £659 and Elite from £949, rising with headcount (CHAS pricing, checked 10 October 2026). Buy one, not three.
TrustMark
The government-endorsed quality scheme for work in and around the home, and the route into funded retrofit. At least 28 of the 557 ask for it.
UTR number
Your Unique Taxpayer Reference from HMRC. Free, and you need it to register for CIS. At least 32 of the 557 ask for it by name. Full guide: UTR number and CIS
VAT registration
Compulsory once your taxable turnover passes the current HMRC threshold. Between VAT-registered businesses in the CIS chain, the domestic reverse charge usually applies. At least 71 of the 557 ask for your VAT number.
The order I'd do it in
When I ran my maintenance company in London, working for housing associations and letting agents through a network of subbies, the rule was simple. Never buy a badge before you can name the client who asked for it.
- Get the free numbers sorted. UTR, CIS registration, VAT if you're over the threshold.
- Get public liability, and employers' liability the day you take anyone on.
- Hold the trade registration your work legally needs. Gas Safe, NICEIC or NAPIT, MCS.
- Only then buy one SSIP scheme, when a client you actually want demands it.
Here's the part people hate hearing: the badge doesn't win the work. It just stops you getting filtered out. You still have to earn the client.
Where Plan@Job fits
Plan@Job is AI-powered project and operations management for construction and property businesses. If you're the Operator, meaning the contractor business managing clients, subcontractors and your own operatives, you run jobs, quotes and your subbies in one place. Daniel Reed, our AI Operations Manager, supports sharing eligible work with the existing vetted network and chasing quotes and proposed dates, with you approving what matters.
If you're the subcontractor, the badges on this page are what checks look at. In supported workflows you can price before you're fully vetted, and checks and approval happen at the stage the job needs them. Nothing gets awarded automatically.
You'll probably want Plan@Job if you're juggling clients and subbies across WhatsApp and spreadsheets and you'd rather spend your time winning work than chasing paperwork. See how it works for contractors, then create your contractor account.
FAQ
What compliance do I need to start as a self-employed contractor in the UK?
Start with the free numbers: a UTR and CIS registration if you work for contractors. Add public liability insurance, then whatever trade registration your work legally needs, like Gas Safe for gas. Accreditations can wait until a client asks.
Is CHAS a legal requirement?
No. CHAS and the other SSIP schemes are commercial accreditations that buyers use to filter suppliers. You need one when a client you want demands it, and because of mutual recognition you rarely need more than one.
Do I need employers' liability insurance if I use subcontractors?
Bona fide subbies running their own business generally don't count. Labour-only subcontractors you direct like staff can count as employees, and then the legal minimum of £5 million applies. If in doubt, speak to your broker.