Builder's Profile vs Constructionline: which does your buyer require?

Builder's Profile and Constructionline appear together in a supplier's prequalification journey, but they are separate schemes with different assessment roles. Builder's Profile says its service lets main contractors ask their own questions of subcontractors. Constructionline offers a preset, independently assessed membership route; its Gold and Platinum products appear on Build UK's current list of recognised Common Assessment Standard (CAS) assessments.

The useful question is therefore not “which logo is better?” It is what evidence the buyer will accept for this opportunity, and whether the supplier needs a buyer-specific Builder's Profile response, a Constructionline assessment, both, or a different recognised CAS assessment. Neither membership is a general legal permission to work.

The practical difference

This comparison follows Builder's Profile's provider FAQ, Constructionline's current Gold membership page and Build UK's recognised-body list. Product names, features and pricing can change. Request current terms from the providers before purchasing anything.

Shared login is not shared approval

Builder's Profile says the services operate alongside each other on a common Once For All platform. Its FAQ says the question sets and approval processes remain separate. That distinction matters when a buyer asks for “Constructionline Gold”, “CAS” or a completed Builder's Profile questionnaire: an account login or an uploaded document on one side should not be presented as proof that the other assessment has been passed.

If you already have a CAS assessment from a different Build UK recognised assessment body, ask whether the buyer accepts it directly or can see your verified data through Build UK's data-sharing route. Do not buy a second assessment solely because a portal lists a preferred provider without checking the buyer's actual requirement.

Work backwards from the invitation

Before renewing or buying either membership, collect four pieces of information from the contracting team:

1. Required outcome: does the buyer require an assessed CAS level, a specific membership product, an SSIP health and safety assessment, a Builder's Profile questionnaire, or a combination?
2. Accepted evidence: will it accept an equivalent assessment from another recognised body, and how should the evidence be supplied?
3. Timing: what must be current at the bid deadline, at award and before mobilisation?
4. Work-specific checks: what extra evidence is required for the trade, site, role or package that a standard prequalification assessment does not establish?

Record the answer against the tender, ideally with the buyer's written clarification. If the wording is ambiguous, ask before assuming. A supplier may meet a general prequalification standard yet still have to show named worker competence, an insurance extension, a safe system of work or site-specific coordination.

Do not confuse CAS, SSIP and buyer-specific approval

CAS is Build UK's broader supplier prequalification question set. An SSIP assessment concerns the health and safety core criteria and assessment category. A buyer-specific questionnaire may address its own commercial or project requirements. SSIP's client guidance explains why buyers should still check experience, trained people and resources for the particular work after an organisational assessment.

For the details of Constructionline's membership products, use our Constructionline guide. For the CAS standard rather than this provider comparison, use our CAS explainer. Keep each page's search task separate: this one helps a supplier decide which provider-specific evidence a buyer is requesting.

Keep one buyer-requirement record

For each opportunity, note the buyer, package, requested scheme and level, accepted equivalent, portal, deadline, responsible person and confirmation source. Store the actual certificate or questionnaire response separately from the decision note. Recheck the requirement if the tender is amended or the appointed legal entity changes.

If you manage several contractors rather than only your own membership, review the existing contractor prequalification software page and ask for a demonstration of how buyer requirements and supplier evidence are recorded. Complys is not Builder's Profile, Constructionline, a CAS recognised assessment body or an SSIP certification scheme, and it does not grant their approvals.

Sources and claim boundaries

• Builder's Profile — new platform FAQs: separate question sets and approval, buyer-specific questions and shared platform. Its migration dates and listed fees are historic, so no dated price claim is used here.
• Constructionline — Gold membership: current Gold positioning and CAS relationship.
• Build UK — Common Assessment Standard: current recognised bodies and assessment products.
• SSIP — Clients: organisational health and safety assessment versus work-specific buyer checks.

Publication gate: Recheck the live buyer/provider instructions and the whole existing Constructionline owner before integration. If that owner already answers the named two-provider choice in sufficient depth, merge this comparison into it rather than publishing a competing URL.