Tax adviser PI · Deep dive

R&D tax credit PI cover — the post-2022 landscape

Reviewed by Matthew Bartlett, Director, Apex Insurance Brokers Limited (FCA FRN 724952) · Published 14 July 2026

HMRC's volumetric enquiry programme starting in 2022 fundamentally reshaped the R&D tax credit adviser risk landscape. What had been a benign specialist niche became a scrutinised segment. Insurer appetite tightened, wordings adjusted, and firms with material R&D exposure now face a materially different renewal conversation than they did before.

What changed in 2022 — and why it matters for PI

HMRC opened enquiry rates on R&D SME scheme claims from roughly 3% pre-2022 to over 20% post-2022. The Autumn Statement 2022 and Spring Budget 2023 restructured the scheme rates. GAAR (General Anti-Abuse Rule) guidance was updated to reference R&D claim structures.

For advisers, this meant three things simultaneously: higher volumes of client HMRC enquiries; higher likelihood of disallowance of previously-filed claims; and higher likelihood of client damages claims against the adviser for filing claims that don't survive HMRC scrutiny.

Insurers responded with a mix of rate loading, wording restriction, and in some cases outright appetite exit.

How R&D-specific PI cover is now structured

Standard extension — still available at most insurers

For general accountancy firms with modest R&D activity (say up to 15% of fee income), most insurers will still include R&D within the standard tax-advisory wording — sometimes with a specific R&D extension endorsement.

Standalone R&D adviser wording — narrower market

For firms with material R&D activity (30%+ of fee income), or specialist R&D boutiques, standalone wording is now required. Fewer insurers in this space; specialist wholesale market for higher volumes.

R&D activity exclusion — some insurers now default

A minority of insurers now default to excluding R&D activity as standard, requiring an explicit extension to write it back in. Firms need to check.

Notification triggers for R&D advisers

The relevant trigger under most wordings is not the client claim — it's the HMRC enquiry opening. Wordings covering ‘circumstances that could give rise to a claim’ require notification when HMRC opens enquiry on a claim the adviser filed.

Under-notification here is a common mistake. Firms should have a documented process for logging HMRC enquiries against filed R&D claims and reviewing quarterly for notification obligations.

Wording tests at renewal

  1. Confirm R&D activity is covered or specifically extended.
  2. Confirm the definition of ‘R&D activity’ in the wording — some exclude specific sub-activities.
  3. Test aggregation: if a common methodology is challenged by HMRC across 20 clients, does one limit apply or twenty?
  4. Confirm HMRC-enquiry-notification treatment under the ‘circumstances’ clause.
  5. Check retroactive date — historic filings should remain covered under the current policy.
  6. Confirm defence-costs treatment — specialist R&D defence is expensive; wording matters.

The insurer appetite map

Broad appetite: general accountancy PI insurers writing R&D as part of the wider tax advisory scope, subject to activity-level limits.

Narrow appetite: specialist tax PI markets, some Lloyd's syndicates via wholesale.

Exclusion: certain retail-focused accountancy insurers now default to excluding R&D unless specifically extended.

Frequently asked

Do all PI wordings cover R&D tax credit advice?
No. Post-2022 many wordings restrict, exclude, or require specific extension for R&D activity. Firms with material R&D work must confirm treatment at renewal.
What does HMRC scrutiny mean for adviser PI?
Higher enquiry rates means more disallowed claims means more client claims against advisers. PI notification triggers on HMRC enquiry openings, not the final disallowance.
How much of my fee income can be R&D before I need specialist wording?
Rule of thumb: up to 15% typically fits standard extensions; 15-30% often needs specific endorsement; 30%+ usually needs standalone specialist wording.
What limit should R&D-heavy firms carry?
Depends on client base and claim quantum. Boutiques typically £5m minimum; firms with large clients often £10m+ with layered programme.
Are R&D advisers subject to any professional-body rules?
Where the adviser is CIOT, ATT, ICAEW or ACCA-regulated, professional body conduct standards apply including PCRT (Professional Conduct in Relation to Taxation).
Can Apex place R&D adviser PI?
Yes. Apex places R&D adviser PI across the range including standalone specialist boutiques via wholesale Lloyd's market.

Related reading