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ICAEW · PII Regulations

ICAEW PII — the 2.5× aggregate limit formula

Reviewed by Apex Insurance Brokers · Published 15 July 2026

ICAEW’s PII Regulations (in force since 1 September 2024) require firms with gross fee income under £800,000 to hold 2.5 times that income, with a £250,000 minimum, and all other firms to hold £2m for any one claim and in the aggregate. Here's how the calculation works.

The formula

The Bye-law: minimum aggregate limit = 2.5 × annual gross fee income

Floor: £250,000 (the minimum for the smallest practices)

Cap: £2m, reached at £800,000 of fees (no requirement to place above this)

Aggregate basis: this is the annual aggregate limit, not per claim.

Worked examples

Edge cases the formula doesn't handle well

Practical placement points

Firms usually place cover materially above Bye-law minimum — the formula is a floor.

Insurers price on turnover, mix of work, claim history and territorial exposure — not just the Bye-law figure.

Aggregate reinstatements available at cost for firms with high single-claim exposure.

Frequently asked

Does ACCA use the same formula?
ACCA requires similar cover levels — broadly 2.5× fees — but consult the ACCA regulations for the exact requirement.
What is 'gross fee income'?
Annual fees invoiced by the firm, before any deductions for costs, VAT or subcontractors.
Are we required to place at the cap?
No. £2m is the most the Regulations require. Firms can place higher voluntarily — and often do.
What about ICAEW audit-registered firms?
The Bye-law minimum still applies, but audit-registered firms typically carry much higher limits given the specific claim exposure.
What happens if fee income spikes mid-year?
Reasonable practice is to review cover with the broker at the point of the change — the Bye-law calculation is based on the current relevant period.
Does this replace insurers' underwriting?
No. Insurers underwrite independently; the Bye-law is a compliance minimum, not a market limit.

Related

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Related reading: Accountants' PI insurance · How much does professional indemnity insurance cost? · Any one claim vs aggregate cover

Compare this against the other UK regulators and professional bodies: PI insurance requirements by professional body.

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