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
£400k firm: 2.5× = £1m. The Regulations require £1m.
£800k firm: 2.5× = £2m. Bye-law requires £2m.
£2m firm: 2.5× = £5m. Bye-law requires £5m.
£8m firm: 2.5× = £20m. Bye-law requires £20m.
£12m firm: fees are over £800k, so the Regulations require £2m.
Edge cases the formula doesn't handle well
Sudden fee-income growth: cover based on last year's fees may be too low.
One-off high-fee assignments: aggregate risk not proportional to steady-state.
Audit registration: often justifies limits materially above Bye-law minimum.
Apex Insurance Brokers Limited is authorised and regulated by the Financial Conduct Authority. Firm reference number 724952. Registered in England and Wales, company number 07014570.
A director will look at it personally
If your firm buys a substantial limit — layered, topped-up or approaching renewal — send the schedule or just call. A second opinion costs nothing and commits you to nothing.