Common Assessment Standard Version 6: What Changes in November 2026?

Another Update Is Coming to the Common Assessment Standard

The Common Assessment Standard has become an increasingly important part of construction supply chain pre-qualification.

Developed by Build UK, the Common Assessment Standard, commonly known as CAS, provides an industry-agreed question set and assessment standards that can be used to pre-qualify suppliers.

Rather than suppliers completing multiple different assessments for different organisations, CAS aims to provide a more consistent approach across the industry.

The Standard is regularly reviewed to reflect changes in legislation, industry requirements and emerging risks.

The next significant update is now approaching.

Version 6 of the Common Assessment Standard will be published on 1 November 2026.

So, what do we know about the changes so far and what should construction businesses be doing to prepare?

What Is the Common Assessment Standard?

The Common Assessment Standard provides a recognised approach to construction pre-qualification.

It covers a broad range of areas used to assess supplier capability and compliance.

The current Version 5 question set includes sections covering:

• Identity
• Financial information
• Corporate and Professional Standing
• Health and Safety
• Environmental
• Quality
• Building Safety
• Fairness, Inclusion and Respect
• Information Security
• Information Management

Companies can achieve either desktop or site-based certification through a Recognised Assessment Body depending on factors including their trade, size and client requirements.

Once certified against CAS by a Recognised Assessment Body, companies can also choose to share their assessment data with other Recognised Assessment Bodies, helping reduce the need to repeat equivalent assessments.

What's Happening on 1 November 2026?

Build UK has confirmed that Version 6 of the Common Assessment Standard will be published on 1 November 2026.

The complete Version 6 question set has not yet been published at the time of writing, so businesses should be cautious about treating any advance summary as the final Standard.

However, a number of important changes have already been confirmed.

One of the most significant relates to how competence is assessed.

Competence Questions Are Moving

Under the current Version 5 Standard, several competence-related questions sit within the Building Safety section.

Version 6 will move these competence questions into the Quality section.

This is important because it means they will apply across the wider supplier base rather than being associated only with businesses completing the Building Safety section.

Until Version 6 is published, suppliers going through CAS certification are still required to successfully complete competence-related questions 135, 136 and 138, even where the remaining dutyholder questions in the Building Safety section do not apply to them.

These questions cover areas including training and supervision, ensuring work meets relevant requirements and keeping up to date with changes in legislation, regulations and industry standards.

Moving them into Quality should make the distinction clearer between general organisational competence and specific Building Safety requirements.

Why Is Competence Becoming More Important?

Construction competence isn't simply about whether an individual holds a particular qualification.

Businesses also need to demonstrate that they have appropriate arrangements in place to ensure people carrying out work have the necessary capability for their roles.

That can include how people are trained and supervised, how organisations ensure work meets required standards and how businesses keep themselves informed when legislation or industry requirements change.

This is particularly important in an industry where suppliers can undertake very different types of work with very different levels of risk.

The movement of competence questions into Quality reinforces the principle that competence is relevant across the wider construction supply chain.

It isn't only a Building Safety consideration.

Changes to the Building Safety Section

Version 6 will also clarify which businesses need to complete the Building Safety section.

Companies that do not undertake building work covered by the Building Regulations will be required to opt out of the section rather than completing questions that aren't relevant to their activities.

This follows clarification around scaffolding and temporary works.

Build UK has confirmed that scaffolding and temporary works do not fall within the definition of building work regulated by the Building Regulations unless they form part of the completed structure.

Under Version 6, scaffolding and temporary works contractors will therefore not generally need to complete the Building Safety section unless the work they undertake falls within the relevant definition of building work.

However, the competence questions moving into Quality will still apply across the wider supplier base.

Why the Distinction Matters

The change highlights an important point about supplier assessment.

Not every question is relevant to every supplier.

A specialist subcontractor, professional consultant, product supplier and scaffolding contractor can present very different risks and responsibilities.

A good pre-qualification process needs to recognise those differences.

Asking businesses to complete questions that have little relevance to their work creates unnecessary administration without necessarily improving supply chain assurance.

At the same time, removing irrelevant questions shouldn't mean removing important checks.

The Version 6 approach appears designed to create a clearer distinction between general competence requirements and specific Building Safety responsibilities.

More Guidance on Evidence

Another expected improvement within Version 6 is additional guidance around the evidence suppliers need to provide.

This is an important part of any supplier assessment.

Answering "Yes" to a question is relatively easy.

Demonstrating that the organisation has appropriate processes, records and evidence behind that answer provides much greater assurance.

Clearer guidance should help suppliers understand what assessors expect and support greater consistency when organisations complete the Standard.

For supply chain owners, better evidence can also improve confidence in the information being used to assess suppliers.

Fraud Prevention Is Also Being Updated

Version 6 is also expected to include updates relating to fraud prevention.

This reflects the changing compliance landscape facing businesses.

Fraud risk is increasingly relevant to organisations assessing the governance and controls of businesses within their supply chain.

The final Version 6 question set will provide the detail on exactly how these requirements are incorporated, so suppliers should review the published Standard carefully once it becomes available on 1 November.

Information Security Remains an Important Area

Information security is another area identified for updates within Version 6.

Construction businesses increasingly share commercially sensitive information, project information, personal data and other digital records across complex supply chains.

Understanding how suppliers protect that information has therefore become an important part of wider supplier assurance.

The current CAS already contains a dedicated Information Security section.

Version 6 is expected to reflect further developments in this area, with the final requirements becoming clear when the updated Standard is published.

What Should Suppliers Do Before 1 November?

Suppliers don't need to wait until November to start preparing.

There are several sensible steps businesses can take now.

First, make sure your existing CAS information and supporting evidence are current.

Pay particular attention to competence arrangements including training, supervision and how your organisation keeps up to date with relevant legislation and industry requirements.

It is also worth reviewing the information you currently hold around Quality, Building Safety, fraud prevention and information security.

Businesses applying for or renewing certification before Version 6 is published should continue to follow the existing requirements and speak to their Recognised Assessment Body if they are unsure what currently applies.

Once Version 6 is published, suppliers should review the final question set rather than relying solely on advance summaries of the changes.

What Should Contractors and Supply Chain Owners Do?

The update isn't only relevant to suppliers completing CAS.

Contractors and clients using CAS within their pre-qualification processes should also review what Version 6 means for their own supplier requirements.

If your organisation maintains its own PQQ alongside CAS, consider whether your existing questions remain aligned with current industry requirements.

You should also ask whether you're requesting information elsewhere that is already being assessed through CAS.

One of the reasons the Common Assessment Standard exists is to reduce unnecessary duplication across construction pre-qualification.

Adding additional questions can still be appropriate where your organisation has specific requirements, but each question should have a clear purpose.

A PQQ Should Never Be Static

Version 6 provides a useful reminder of something much broader.

A supplier questionnaire should never be created once and then forgotten.

Legislation changes.

Standards change.

Industry guidance develops.

New risks emerge.

Client expectations evolve.

The questions being asked of suppliers need to evolve too.

At the same time, more questions don't automatically mean better supplier assurance.

The objective should be to collect relevant information that helps an organisation understand whether a supplier is capable, compliant and appropriate for the work being considered.

Regularly reviewing your PQQ helps keep that process meaningful.

Don't Wait Until a Supplier Is Needed

There is another practical consideration for contractors.

If your supply chain assessment requirements change, the worst time to discover a supplier hasn't provided the necessary information is when you're trying to appoint them to a project.

Keeping supplier information current can help identify gaps earlier.

This gives suppliers time to provide updated evidence and gives assessors time to review it before the supplier is urgently required.

Changes such as CAS Version 6 therefore shouldn't only be viewed as questionnaire updates.

They're also an opportunity to review how efficiently supplier information is being managed across the wider supply chain.

How Mobilize Can Help

Liaison's Mobilize platform helps construction organisations manage supplier onboarding, PQQs, assessments and ongoing compliance information within one central environment.

Question sets can evolve as requirements change, allowing supply chain owners to maintain assessments that reflect current expectations rather than relying on questionnaires created several years earlier.

Supplier information, supporting documentation and assessments can then form part of a wider supplier record.

This helps organisations maintain greater visibility of the information supporting supplier approval and identify where further information or reassessment may be required.

As industry standards continue to change, having a flexible approach to supplier assessment becomes increasingly valuable.

What Happens Next?

The key date is 1 November 2026.

That is when Build UK has confirmed Version 6 of the Common Assessment Standard will be published.

Until then, businesses should continue working to the current requirements while preparing for the changes already announced.

Once the final Standard becomes available, suppliers, contractors and clients should review the complete question set and assessment requirements carefully.

Further details may clarify or expand on the changes already announced.

For the latest official information, businesses should refer to Build UK's Common Assessment Standard guidance and their Recognised Assessment Body where appropriate.

Conclusion

The Common Assessment Standard continues to evolve alongside the construction industry.

Version 6 will bring a clearer distinction between general competence and specific Building Safety requirements, while also introducing updates in areas including fraud prevention and information security.

For suppliers, the message is simple.

Make sure your information and evidence are current and be ready to review the new Standard when it is published.

For contractors and clients, the update provides another opportunity to look at the questions you're asking your supply chain and whether they still reflect the risks and requirements that matter today.

Because effective pre-qualification isn't about asking more questions.

It's about asking the right ones.