Explainer

What is CHAS accreditation?

CHAS is one of the UK's best known contractor assessment schemes. Most subcontractors meet it because a main contractor asked for it, then spend the next year hunting for the paperwork that proves it is still true.

7 min read Updated 2 August 2026Recently updated

What CHAS actually is

CHAS (the Contractors Health and Safety Assessment Scheme) is a third-party assessment body. You submit a set of documents about how your business manages health, safety and related risks, an assessor reviews them against a published standard and you receive accreditation for twelve months. It began as a local authority initiative and is now one of several schemes recognised under the Common Assessment Standard, which means a single assessment can satisfy multiple buyers.

What assessors look for

The exact list varies by level, but the shape is consistent. Assessors want to see policies that exist, are current and are signed, plus evidence they are used in practice.

  • Health and safety policy, signed and dated within the last twelve months.
  • Risk assessment and method statement (RAMS) examples for real work you have carried out.
  • Employers' liability and public liability insurance certificates, in date.
  • Competence evidence for operatives, such as CSCS cards and trade tickets.
  • Training records, toolbox talk records and accident or near-miss records.
  • Named competent health and safety advice, in-house or retained.

The levels, and which one you need

Most confusion is about level rather than content. Pick the level your clients actually ask for, not the highest one available.

LevelWho it suitsTypical trigger
Foundation / ElementarySole traders and small trades doing low-risk workA single client asked for CHAS as a tick box
AdvancedSubcontractors on larger sites with staff and plantMain contractor framework or tier 1 supply chain
Elite / Common Assessment StandardContractors bidding for public sector and large frameworksProcurement portals recognising the Common Assessment Standard

What CHAS does not do

This is where teams get caught out. Accreditation proves you passed an assessment on a date. It does not prove your insurance is in date today, that the RAMS for next week's job exist or that the operative arriving on site holds a valid card. Clients know this, which is why a CHAS certificate almost never ends the document conversation. Expect to supply live certificates alongside it.

Getting through the assessment first time

Rejections are nearly always administrative rather than substantive. The work was fine, the evidence was stale.

  1. Collect every document into one place before you start the application.
  2. Check each expiry date and renew anything inside 60 days of lapsing.
  3. Re-sign and re-date your health and safety policy if the signature is over a year old.
  4. Pick RAMS examples that match the work types you are claiming competence for.
  5. Redact personal data you do not need to share, such as full dates of birth on training records.
  6. Keep the submitted set as your baseline so next year's renewal is a diff, not a rebuild.

Keeping it true for the other 51 weeks

Accreditation is an annual event. The evidence behind it expires on its own schedule. The teams that renew painlessly are the ones that track each document against its own expiry date with a named owner and a reminder, so the renewal pack is already assembled when the reminder lands. That is exactly the job Credbase does: one record per document, an owner, an expiry date and a share link you can send to a client or an assessor without rebuilding anything.

Frequently asked questions

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