Aggregation Clauses by Regulator UK
An aggregation clause is the contractual mechanism by which multiple related claims against a professional firm are treated as one claim for the purpose of the limit of indemnity, the deductible, and (where relevant) the aggregate cap. Whether a set of claims aggregates or stays separate can turn a series of nine £100,000 claims into a single £900,000 problem the policy is designed to absorb, or into nine independent triggers each answering to its own limit and excess.
Accountants — ACCA Professional Indemnity Insurance Regulations
Insurance intermediaries and other firms whose PI requirement flows from MIPRU set a minimum limit but do not prescribe aggregation language. MIPRU 3.2.7R currently requires cover of at least €1,300,380 per single claim and, in the aggregate, the higher of €1,924,560 or an amount equivalent to ten per cent of annual income up to a cap of £30 million. IFA and mortgage-adviser policies are usually written on an any-one-claim basis with a separate aggregate cap across the policy year, and the aggregation wording within the policy is negotiated between insurer and firm rather than dictated by the FCA Handbook.
The Supreme Court decision every PI conversation returns to
The aggregation clause sits alongside the limit structure of the policy, and the two need to be read together. The SRA MTC is written on an any-one-claim basis with no aggregate cap on the primary layer: after aggregation, the aggregated claims are treated as one claim, and the policy responds up to the full limit; a second unrelated aggregated claim gets the full limit again. Excess-of-loss layers may add aggregate caps above the primary, but the primary layer is genuinely uncapped by aggregate.
Most non-MTC PI policies are structured differently. The typical wording gives an any-one-claim limit paired with an aggregate cap across the policy year. When a large aggregated claim occurs it drains the aggregate, and any subsequent unrelated claim in the same year must share what remains. A headline number that looks the same on paper can produce very different outcomes depending on which basis it is written on.
How Apex helps
Apex Insurance Brokers is an FCA-authorised specialist broker for professions and small-business PI. Our work is focused on solicitors, accountants, surveyors, architects, IFAs, engineers, IT consultants and management consultants — the sectors where aggregation clauses do the most work in practice. We place across the market for our target sectors, compare wordings side by side (including the operative aggregation language, the excess structure, and the aggregate cap where relevant), and document the sizing exercise so the limit chosen reflects the aggregated exposure the work generates. The firm is authorised and regulated by the Financial Conduct Authority under firm reference number 724952. Matthew Bartlett is Director and holds the SMF3, SMF16 and SMF17 senior manager functions.
Frequently asked questions
What is an aggregation clause in PI insurance?
An aggregation clause is the contractual provision that decides when multiple claims are treated as one for the purposes of the limit of indemnity, the deductible, and the aggregate cap. It matters most where the same act, defect, or pattern of conduct gives rise to claims from many clients — the aggregation wording determines whether they share one limit or trigger the policy repeatedly.
Apex Insurance Brokers Limited is authorised and regulated by the Financial Conduct Authority. Firm reference number 724952.