PI requirements · ARB and RIBA · As at September 2026

Architects’ PI insurance requirements: ARB and RIBA

The Architects Registration Board requires ‘adequate and appropriate’ cover and expects a minimum of £250,000; RIBA Chartered Practice status requires ‘appropriate’ cover with no fixed figure. Here is the current position, the run-off rule, and how to judge whether the minimum is enough.

Part of: PI insurance requirements by professional body

In short

Architects need professional indemnity insurance of at least £250,000 for each and every claim. That minimum is set by ARB’s PII guidance, published on 19 June 2025 to support the new Architects Code, which came into force on 1 September 2025 and replaced the 2017 Code. Under the Code’s Standard 4 (Professional practice), architects should ensure their liabilities are covered by ‘adequate and appropriate’ professional indemnity insurance. Fire-safety and cladding cover may be held on an aggregate basis. ARB expects at least six years’ run-off cover on cessation, or five years in Scotland. RIBA Chartered Practice status requires cover ‘appropriate for the work undertaken’ but sets no fixed figure. These are the positions as at September 2026; verify the current requirement with ARB and RIBA, as they change. Apex is an independent, director-owned broker that checks your limit and run-off against the work you actually do, and returns competing quotes.

What ARB and RIBA requires

Architects in the UK are regulated by the Architects Registration Board (ARB). The Architects Code, which replaced the 2017 Code on 1 September 2025, has six Standards. Under Standard 4 (‘Professional practice’), architects meet the Standard when they ‘ensure their liabilities are covered by adequate and appropriate professional indemnity insurance’ (example 4.7). ARB’s PII guidance adds that you should make sure your employees’ work is covered too.

The Code does not name a single statutory figure, but ARB’s PII guidance states that ARB ‘would expect a minimum level of indemnity to be £250,000’, acquired on an each-and-every-claim basis (with exceptions noted for fire-safety and cladding claims). There is no banding by fee income — it is a stated minimum expectation of £250,000.

RIBA is a membership body, not the regulator. A RIBA Chartered Practice must declare that it holds ‘professional indemnity insurance cover appropriate for the work undertaken by the practice’, but RIBA sets no fixed monetary minimum — adequacy is left to the practice, aligned with ARB’s expectation.

Rule and date. ARB Architects Code in force from 1 September 2025, Standard 4, example 4.7 (‘adequate and appropriate’), and ARB’s PII Guidance published on 19 June 2025 (the £250,000 minimum expectation, each-and-every-claim basis, and six-year run-off, five in Scotland); RIBA Chartered Practice criterion (‘appropriate’ cover, no fixed figure). As at September 2026 — verify the current requirement with ARB (and, for Chartered Practice, RIBA) (ARB PII Guidance), as these requirements change.

Each claim vs aggregate: why the basis matters

Two policies can both say ‘£2 million’ and protect you very differently. The difference is the basis of the limit.

Each and every claim (or ‘any one claim’). The full limit is available for every separate claim, however many you face in a policy year. A firm on a £1 million each-and-every policy is covered for three £1 million claims in the same year.
In the aggregate. The limit is the most the insurer will pay in total across the whole year, added together. On a £1 million aggregate policy, those same three claims exhaust the cover after the first.

ARB expects the £250,000 to be an each-and-every-claim figure, so the full limit is available for each separate claim rather than shared across a year.

This is why a firm holding £1 million in the aggregate can still fail a requirement written as ‘£1 million for any one claim’ — the number matches but the basis does not. Read the basis of your requirement, not just the figure, and check whether defence costs sit outside the limit or erode it.

Run-off: cover after you stop

Professional indemnity is written on a claims-made basis: the policy that answers a claim is the one in force when the claim is made or notified, not the one you held when you did the work. So when you stop trading, the cover does not follow your old work automatically — a claim can still arrive years later, and there is no live policy to meet it unless you have bought run-off cover.

ARB expects architects to maintain a minimum of six years’ run-off cover on ceasing to practise — five years if practising in Scotland — at the level of the final year of practice. It also warns architects to be aware of longer liabilities: twelve years for a contract executed as a deed, and claims under the Defective Premises Act.

Run-off matters most on retirement, closure, a merger or a change of legal structure. A retroactive date that reaches back over all your past work is what keeps that earlier work covered; if you change insurer or broker, protecting that date is the point to watch.

Is the minimum enough?

A regulatory minimum is a floor, not a recommendation. ARB sets the least cover you may hold and still practise; it does not promise the figure is enough for your work. A single claim on a large contract, a valuation, a set of accounts or a piece of advice can run well past the minimum once the loss and the other side’s legal costs are added.

Building work carries long-tail liability, and the sums at stake in a defect or fire-safety claim can be many times £250,000. ARB stresses cover must be ‘appropriate’ to the work, so the expected minimum is rarely the right answer for anything but the smallest practice.

Judge the limit against your own exposure: the size of the contracts you sign, the value of the work you touch, what your clients and their lenders require in writing, and your claims history. Our minimum-limit calculator and our guide to how much professional indemnity insurance you need walk through that. A broker’s job is to place the right limit, not just the lowest one you are allowed to buy.

How Apex helps you meet it

Apex Insurance Brokers is an independent insurance broker established in 2009 and based in Bristol, owned entirely by its directors and directly authorised by the FCA since 2016, placing professional indemnity insurance for architects across the UK. It is one of the longest-established independently owned professional indemnity specialists in the UK, and it is not for sale: we have declined approaches to buy the firm. We are not tied to any single insurer or professional-body scheme, we do not run our own policy or underwriting, and we have no placement quotas. We have access to over 30 markets, including Lloyd’s syndicates via wholesale, and we usually return three or four competing quotes set out so you can compare them like for like. Every client has a named broker — the same person from first quote to renewal — and every claim notification gets director-level attention rather than a call-centre queue.

Owned by its directors, not for sale. No consolidator, no private-equity owner, no external shareholders — and we have declined approaches to buy the firm. Read the Apex Independence Charter.
Independent, not tied. No single-insurer scheme, no in-house policy, no placement quotas — the recommendation is the one that fits, not the one we are paid to push.
Over 30 markets, including Lloyd’s. Specialist UK PI insurers and Lloyd’s syndicates via wholesale, so a risk that one underwriter dislikes can still be placed properly with another.
Usually three or four competing quotes, laid out side by side — limit, excess, retroactive date, exclusions and premium — with a plain-language note on the trade-offs.
The stay-put letter. If your existing cover is right, we say so in writing, free and without obligation. How the stay-put letter works.
A named broker all year. The person who places your cover is the person who picks up the phone at renewal, on a mid-term change, or when a letter of claim lands.
Director-level attention on claims. We help you notify circumstances early and in the right form, stay involved once the insurer’s panel solicitors are appointed, and tell you plainly where you stand.
Directly authorised by the FCA since 2016, not an appointed representative trading under someone else’s permissions.

Frequently asked

What is the minimum PI insurance for an architect?

£250,000 for each and every claim. That is the minimum in ARB’s PII guidance, with an exception for fire-safety and cladding claims, which may be covered on an aggregate basis. There is no banding by fee income. The Architects Code in force from 1 September 2025 also requires cover to be ‘adequate and appropriate’ for your work. This is the position as at September 2026; confirm the current expectation with ARB.

Does ARB set a fixed legal minimum, or is it an expectation?

The Architects Code (Standard 4, in force from 1 September 2025) requires ‘adequate and appropriate’ insurance rather than a fixed statutory figure. ARB’s PII guidance then states it would expect a minimum of £250,000. So the £250,000 is a stated expectation backed by the Code’s ‘adequate and appropriate’ duty, which ARB can enforce through its conduct process.

Does RIBA require a different amount?

No fixed amount. RIBA is a membership body, not the regulator. A RIBA Chartered Practice must declare it holds cover ‘appropriate for the work undertaken by the practice’, but RIBA sets no monetary minimum, leaving adequacy to the practice in line with ARB’s expectation. Meeting ARB’s £250,000 expectation is the practical baseline.

Do architects need run-off cover, and for how long?

Yes. ARB expects a minimum of six years’ run-off cover on ceasing to practise, at the level of your final year, and five years if you practise in Scotland. It also warns of longer liabilities — twelve years for work under a deed, and claims under the Defective Premises Act — so the six years is a minimum, not a safe stopping point.

What if my practice does more than architecture?

Your cover must be appropriate to everything the practice does, and the wording must not exclude a service you provide — principal designer duties, project management or expert witness work, for example. If you carry on separately regulated activities, you may face another body’s requirement too. A broker checks the wording matches your actual work.

Is the £250,000 minimum enough?

For most practices, no. It is an expected floor, not a measure of exposure. A single defect, fire-safety or design claim can run to many times £250,000 once remediation and legal costs are added, and ARB stresses cover must be ‘appropriate’ to the work. Our calculator and how-much guide help you size the right limit.

Who checks that I comply?

ARB, through the Architects Code. Failing to hold adequate and appropriate insurance can be referred to ARB’s Professional Conduct Committee. RIBA separately checks the Chartered Practice declaration at membership. In practice you confirm your cover and must be able to evidence it if asked.

Check your cover meets the minimum

Send your current schedule and renewal terms. A named Apex broker checks the limit, basis and run-off against your body’s requirement and returns competing quotes set out so you can compare them like for like. Or call 0117 325 0027.

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Apex Insurance Brokers Limited is authorised and regulated by the Financial Conduct Authority. Registered in England and Wales, company number 07014570. This page is general information about professional indemnity insurance requirements, not advice on your individual circumstances, and it does not set, guarantee or replace the rules of any professional body or regulator. Every requirement shown is the position as at September 2026 against the source linked beside it; these requirements change, so confirm the current rule with the body itself before you rely on it. Apex does not set or enforce any professional body’s minimum.