United Kingdom: Complaints about an adviser

A complaint works best when it goes to the right place in the right order, in writing, with the engagement letter and the correspondence attached. Take advice before you start if the claim itself is in doubt, because a complaint about the adviser and a correction of the return are separate matters with separate deadlines; the when things go wrong pages cover the second.

Put the complaint to the firm in writing first: what was agreed, what happened and what you want done. ICAEW, for example, will look at a complaint about a member or regulated firm only once the matter has been raised with the firm in writing and the firm has had 28 days to respond.1Source 1ICAEW, How to make a complaint: ICAEW can investigate once the matter has been raised with the firm in writing with 28 days to respond; it cannot investigate "a fee dispute" or "a commercial or contractual disagreement"; "ICAEW does not operate a general compensation scheme". The fee disputes page covers what to do about a disputed invoice while the complaint runs.

If the adviser belongs to a professional body, that body's complaints process is the next step. Check membership first using the credentials page.

• ICAEW investigates professional misconduct by its members and regulated firms. It cannot investigate a fee dispute or a commercial or contractual disagreement, and it does not operate a general compensation scheme.1Source 1ICAEW, How to make a complaint: ICAEW can investigate once the matter has been raised with the firm in writing with 28 days to respond; it cannot investigate "a fee dispute" or "a commercial or contractual disagreement"; "ICAEW does not operate a general compensation scheme".
• CIOT and ATT members are subject to the Taxation Disciplinary Board, which operates independently of the two bodies. Complaints are made on its online form, within twenty-four months of the events. The Board cannot intervene in fee disputes, which it considers a matter for the courts.2Source 2Taxation Disciplinary Board, Guidance for the public: "TDB operates independently of CIOT and ATT"; complaints within twenty-four months of the events; "TDB cannot intervene in fee disputes, as it considers that the courts are the proper forum for such matters".

Other bodies have their own processes; ask the adviser which body applies.

HMRC's standard for agents sets out what it expects from anyone who represents or advises taxpayers.3Source 3HMRC, HMRC: the standard for agents (9 February 2026). HMRC's own 2022 review noted that it did not then have a clear way for poor agent standards to be reported. It said that poor behaviour by an agent affiliated to a professional body can be reported by the client to that body.4Source 4HMRC, Raising standards in the tax advice market: HMRC's review of powers to uphold its Standard for Agents (10 March 2022).

The position changed in 2026. Tax advisers who interact with HMRC for clients must now register. From 18 August 2026 sanctions may apply to advisers who fail to meet the registration conditions or who act without being registered (checked 13 October 2026).5Source 5HMRC manual MTAR30700 (8 October 2026); MTAR10100 (8 October 2026). HMRC can fine an adviser £5,000 for each prohibited interaction with HMRC on behalf of clients while subject to a compliance notice, and more for repeat cases. It can publish the details of sanctioned advisers.6Source 6HMRC manual MTAR30400, financial penalties for prohibited interactions (8 October 2026), Finance Act 2026 sections 234 and 235; MTAR30520, power to publish details of sanctioned tax advisers (8 October 2026), Finance Act 2026 section 246. HMRC has also said that it takes action against agents who breach its standard in R&D claims, including penalties and refusing to deal with an agent.7Source 7HMRC, HMRC's approach to Research and Development tax reliefs (17 July 2023).

The HMRC manual pages read for this page describe no public route for reporting an adviser. HMRC's report tax fraud service takes reports of avoidance or evasion but does not mention tax agents or advisers.8Source 8GOV.UK, Report tax fraud or avoidance to HMRC. If you want to tell HMRC about an adviser, ask HMRC how. Any sanction is a matter between HMRC and the adviser.

A complaint to a professional body can lead to discipline of the member; a report to HMRC can lead to action against the adviser. Neither changes the company's own tax position, which is decided by the return and any compliance check, and neither recovers a fee: ICAEW and the Taxation Disciplinary Board both say they do not take fee disputes.1Source 1ICAEW, How to make a complaint: ICAEW can investigate once the matter has been raised with the firm in writing with 28 days to respond; it cannot investigate "a fee dispute" or "a commercial or contractual disagreement"; "ICAEW does not operate a general compensation scheme". 2Source 2Taxation Disciplinary Board, Guidance for the public: "TDB operates independently of CIOT and ATT"; complaints within twenty-four months of the events; "TDB cannot intervene in fee disputes, as it considers that the courts are the proper forum for such matters". A fee dispute is a contract matter between you and the firm, and the engagement letter is where it is decided; take legal advice before withholding any payment.

• Complaints about an adviser in general terms, and fee disputes
• Checking an adviser's credentials and if your claim is reviewed in the United Kingdom
• Switching advisers

Sources

1. ICAEW, How to make a complaint: ICAEW can investigate once the matter has been raised with the firm in writing with 28 days to respond; it cannot investigate "a fee dispute" or "a commercial or contractual disagreement"; "ICAEW does not operate a general compensation scheme".    Back
2. Taxation Disciplinary Board, Guidance for the public: "TDB operates independently of CIOT and ATT"; complaints within twenty-four months of the events; "TDB cannot intervene in fee disputes, as it considers that the courts are the proper forum for such matters".   Back
3. HMRC, HMRC: the standard for agents (9 February 2026).  Back
4. HMRC, Raising standards in the tax advice market: HMRC's review of powers to uphold its Standard for Agents (10 March 2022).  Back
5. HMRC manual MTAR30700 (8 October 2026); MTAR10100 (8 October 2026).  Back
6. HMRC manual MTAR30400, financial penalties for prohibited interactions (8 October 2026), Finance Act 2026 sections 234 and 235; MTAR30520, power to publish details of sanctioned tax advisers (8 October 2026), Finance Act 2026 section 246.  Back
7. HMRC, HMRC's approach to Research and Development tax reliefs (17 July 2023).  Back
8. GOV.UK, Report tax fraud or avoidance to HMRC.  Back