Guide · UK procurement policy
PAS 91 is retired. What the Common Assessment Standard means for your tenders
Published 14 July 2026 · Sources linked throughout · This is a plain-English guide to published government and industry information, not legal or procurement advice.
1The short version
If you've bid for construction or works contracts before, you'll know PAS 91 — the standard pre-qualification questionnaire (PQQ) format many buyers used to vet suppliers before letting them tender. PAS 91 was formally withdrawn by the British Standards Institution in April 2023 and is no longer maintained. Its replacement, the Common Assessment Standard (CAS), built by Build UK with Constructionline, is now the industry-agreed question set — and central government guidance PPN 03/24 (March 2024) recommends contracting authorities use it for construction procurement.
2Does this actually apply to your contracts?
Mostly, not directly — and that's the detail people miss. PPN 03/24 is a recommendation, not a mandate, and it's primarily aimed at higher-value works: authorities are advised to use CAS above the works threshold (around £5.337m), with proportionate use below that. Most SME trade contracts — the £90k–£640k range this site's own analysis of 882 live UK tender notices found typical for trade sectors — sit well under that line. In practice this means: don't assume every ITT will demand full CAS pre-qualification, but do expect more buyers to reference it or ask CAS-style questions even on smaller lots, because it's becoming the shared vocabulary of PQQs. Check the specific SQ/PQQ section of each ITT rather than assuming either way.
3What CAS actually is (and isn't)
CAS is a single, standardised set of pre-qualification questions covering the kind of ground a construction/works buyer needs answered before it'll let you tender at all — company and financial details, health & safety management, environmental management, quality management, equality and modern slavery policies, and more. The point of standardising it is that a supplier can complete the assessment once and reuse it across multiple buyers, rather than filling in a differently-worded PQQ for every authority.
What CAS is not a replacement for: your SSIP health & safety accreditation (CHAS, SafeContractor, Constructionline Gold, SMAS and similar) is a separate, narrower assessment focused specifically on health & safety competence. CAS is broader — it covers PQQ ground beyond H&S — but many buyers still expect SSIP accreditation as one input into (or alongside) it. The two aren't interchangeable, and a tender can ask for both.
4What to actually do about it
| If you bid for… | Practical takeaway |
|---|---|
| Sub-£1m works/trade contracts (the SME norm) | Read the SQ/PQQ section of each ITT individually — full CAS pre-qualification is unlikely to be required, but the underlying question categories (financial standing, H&S, environmental, quality, policies) are near-universal regardless of format. |
| Larger works contracts (multi-£m) | Expect CAS or CAS-equivalent pre-qualification. If you don't already hold an up-to-date CAS assessment via an accreditation body, budget time to complete one before bidding at this scale. |
| Any contract where you already hold SSIP accreditation | Keep it current regardless — it remains a distinct, commonly-required credential, not something CAS quietly absorbs. |
5Where this fits with your own readiness
Every category CAS and PAS 91 both trace back to — financial standing, insurance, SSIP/health & safety accreditation, quality and environmental management, core policies — is exactly what our free readiness scan checks in ten minutes, because it's drawn from the same selection-stage ground buyers actually test on. If you're not sure where your business stands against any of this, that's the fastest way to find out.
Check your readiness in 10 minutes
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Sources: Constructionline, "Demystifying PPN 03/24"; Constructionline on PAS 91's withdrawal; Constructionline on the Common Assessment Standard; CHAS, "PAS 91 vs SSIP vs CAS". This guide is general information based on public industry sources, not legal or procurement advice — always check the specific SQ/PQQ wording of your own ITT, since individual buyers set their own requirements.