Professional indemnity

Aggregation clauses by regulator: SRA, RICS and ICAEW side by side

In short: Aggregation decides whether a set of related mistakes is one claim against one limit or many claims against many limits. The three regimes compared here approach it very differently: the SRA prescribes an aggregation clause in its minimum terms, RICS prescribes a minimum policy wording that aggregates claims arising from the same originating cause, and ICAEW prescribes limits but no aggregation wording at all, leaving that to the insurer’s own policy. This comparison is deliberately partial — it covers only what can be confirmed from each regulator’s own published rules.

Category: Professional indemnity
Also known as: aggregation by regulator, one claim or many, series of claims, minimum terms aggregation
Related concepts: aggregation clause, SRA minimum terms, professional indemnity insurance

Why aggregation decides your real limit

A limit of indemnity written on an any-one-claim basis looks generous until you ask how many claims a bad year produces. If fifty clients were advised wrongly in the same way on the same scheme, the aggregation clause decides whether the firm has fifty limits or one. That single question routinely matters more than the headline limit, and it is the part of a professional indemnity programme buyers understand least. The general mechanics are covered in our entry on the aggregation clause; this page compares what different regulators actually prescribe.

SRA: an aggregation clause written into the minimum terms

The SRA is unusual in prescribing the aggregation wording itself. Under the minimum terms and conditions, claims may be regarded as one claim where they arise from one act or omission; one series of related acts or omissions; the same act or omission in a series of related matters or transactions; or similar acts or omissions in a series of related matters or transactions. The minimum terms also provide that all claims against one or more insured arising from one matter or transaction will be regarded as one claim.

The third and fourth limbs have produced the most litigation. In AIG Europe Ltd v Woodman [2017] UKSC 18 the Supreme Court considered “a series of related matters or transactions” and held that the transactions must be related to one another in an intrinsic sense — a relationship arising from an external connecting factor is not enough — and that applying the phrase is an exercise of judgment on the facts rather than the application of a formula. See our fuller treatment of the SRA minimum terms.

RICS: a prescribed minimum policy wording built on originating cause

RICS takes a different route. Rather than prescribing an aggregation clause in its requirements, it publishes an approved minimum policy wording that insurers must at least match. That wording defines a series of claims by reference to claims that arise directly or indirectly from the same originating cause, and applies the indemnity limit to each claim or any series of claims. The requirements document separately obliges firms to hold cover on an each and every claim basis, or on an aggregate basis with unlimited round-the-clock reinstatement.

“Originating cause” is generally understood in the case law as one of the wider aggregating expressions, because it looks back to a single underlying source rather than requiring the matters or transactions themselves to be related to each other. Two firms in different professions can therefore be aggregated on quite different tests on very similar facts.

ICAEW: limits prescribed, aggregation left to the market

The ICAEW Professional Indemnity Insurance Regulations effective from 1 September 2024 set a minimum limit of indemnity in each policy year of at least £2 million for any single claim and in the aggregate, with a lower alternative for smaller firms: a firm with gross fee income below £800,000 must hold a limit equal to two and a half times its gross fee income, subject to a minimum of £250,000. The maximum aggregate excess must not exceed the higher of £3,000 or 3% of the firm’s gross fee income.

What the regulations do not do is prescribe an aggregation clause or a minimum policy wording. The limit may be arranged on an each and every claim basis, which can provide more cover in total across a year, or on an aggregate basis covering all claims in the year. Aggregation for an ICAEW firm is therefore a question of the insurer’s own wording, and two compliant policies can behave very differently.

What the comparison shows

Three regulators, three architectures. The SRA fixes the aggregation clause, so solicitors’ firms all start from the same wording and argue about its application. RICS fixes a minimum policy wording containing a same-originating-cause test, so surveyors start from a different and generally wider aggregator. ICAEW fixes the money but not the mechanism, so accountancy firms have to read their own policy to know what they have bought.

The practical conclusion is the same in all three cases: the limit on the schedule is not the amount of cover, it is the amount of cover per claim as that policy defines a claim. For any firm doing volume or scheme work, that definition should be looked at before the limit is set, not after a claim arrives.

Where this comparison stops

This is a partial comparison, and deliberately so. It covers only the three regimes above, and only what is confirmable from each regulator’s own published rules and wordings as at August 2026. Other regulated professions operate their own minimum terms with their own aggregation language, and regulators revise these documents; figures and wordings should always be checked against the current version before you rely on them. Where a point could not be confirmed from a primary source it has been left out rather than approximated. See also MIPRU 3 for the position of FCA-regulated intermediaries, whose own PI limits are set by the regulator but whose aggregation wording, like ICAEW firms’, is a matter for the policy.

Frequently asked questions

Which of these regimes has the widest aggregation wording?

The RICS approved minimum wording aggregates claims arising directly or indirectly from the same originating cause, which is generally understood as a wider test than the SRA formulation, because it does not require the matters or transactions to be related to each other. Outcomes still turn on the facts of the particular case.

Does ICAEW prescribe an aggregation clause?

No. The ICAEW regulations set minimum limits of indemnity and a maximum excess, and allow the limit to be arranged on either an each and every claim basis or an aggregate basis, but they do not prescribe aggregation wording. For an ICAEW firm, aggregation is governed by the insurer's own policy wording.

Why does aggregation matter more than the headline limit?

Because the limit applies per claim as the policy defines a claim. If a series of related errors aggregates into one claim, a firm that believed it had many limits available has one. For firms doing repetitive or scheme-based work, the aggregation clause is the single most important term in the policy after the limit itself.

Related entries

This entry is part of the Apex Insurance Wiki. It is insurance information about how UK cover responds to the rules described, and is not legal or regulatory advice. Rules, limits and wordings change; the position stated is as at August 2026. Check the primary source and take your own professional advice before relying on any of it.

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Apex Insurance Brokers Limited is authorised and regulated by the Financial Conduct Authority (FRN 724952). This page is general information, not advice on a specific policy.

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