HMRC have released new guidance on what happens if an unregistered or suspended tax adviser interacts with HMRC. Further guidance has also been released on what advisers can do if they disagree with HMRC's decision about their registration.
HMRC's Mandatory tax adviser registration is due to begin on 18 May 2026. All tax advisers who interact with HMRC on behalf of clients will be required to register. Once registered, tax advisers will need to continue to meet registration requirements or risk having their registration suspended by HMRC.
HMRC's new guidance advises that they may sanction a tax adviser who interacts with them while:
- They are unregistered.
- Their registration is suspended.
- Interacting includes contacting HMRC directly, sending returns, claims, or documents.
HMRC have advised that they will, where possible, support tax advisers in complying with the registration requirements before applying any suspension or sanction.
Tax advisers will have a three-month transition period from the date they need to register. HMRC will not apply a sanction during this time if a tax adviser has applied to register and is awaiting HMRC's decision.
Reasons for suspension
HMRC may suspend a tax adviser registration if:
- The business or relevant individual no longer meets the registration requirements.
- The business or relevant individual's behaviour is below HMRC's Standard for agents.
Suspension means a tax adviser will not be able to access their Agent Services Account or interact with HMRC on behalf of their clients.
HMRC will contact any tax adviser whom they believe is not meeting the registration requirements:
- 30 days will be given to correct any identified issues.
- Issues relating to unpaid tax will be given 60 days from initial contact.
- Extensions may be granted on a case-by-case basis.
- If the issues highlighted are not corrected, HMRC will issue a notice of suspension.
- The suspension will be lifted once the issues are resolved.
- HMRC may request evidence to prove the issues have been resolved.
If HMRC believes a tax adviser's behaviour is not meeting their standards, a fixed-term suspension may be issued.
- This will come into effect 30 days after receiving the notice of suspension and lasts for up to 12 months.
Sanctions for interacting with HMRC whilst unregistered or suspended
HMRC have provided the following table in their new guidance, outlining the penalties for interacting with them while unregistered or sanctioned.
| Type of prohibited interaction | Sanction imposed | What this means |
|---|---|---|
| 1st prohibited interaction | Formal compliance notice | The tax adviser must stop interacting with HMRC on behalf of clients. This applies until the tax adviser becomes registered or the suspension is lifted by HMRC. |
| Each prohibited interaction after the formal compliance notice | £5,000 penalty | If the tax adviser continues to interact with HMRC after receiving the formal compliance notice, they will be charged £5,000 for each prohibited interaction |
| 5th or any further interaction within a two-year period (starting on the date of the 1st penalty) | £10,000 penalty and a 12-month temporary ban | If you receive five penalties within a two-year period (starting on the date of the 1st penalty), the 5th penalty will be £10,000 and the tax adviser will not be able to interact with HMRC on behalf of clients for 12 months. Any further prohibited interactions in the same two-year period will result in a £10,000 penalty each time |
| Prohibited interaction whilst on a 12-month temporary ban | Permanent ban and £10,000 penalty | If the tax adviser makes a prohibited interaction whilst on a 12-month ban, they will not be able to interact with HMRC on behalf of clients again and will receive a £10,000 penalty for the prohibited interaction and any further interactions. |
| Prohibited interaction whilst on a permanent ban | £10,000 penalty | The tax adviser will receive a £10,000 penalty per prohibited interaction whilst on a permanent ban |
Any temporary or permanent ban will be notified in writing by HMRC, and the tax adviser will have 30 days to respond.
- HMRC may publish information about tax advisers to whom they issue a temporary or permanent ban.
- HMRC will tell the tax adviser in advance if publication is to be made, and the tax adviser will have 30 days to respond.
If a tax adviser disagrees with a decision about their registration
HMRC's new guidance advises that where a tax adviser disagrees with a decision made about their registration, they can:
- Accept HMRC's offer of a statutory review.
- Appeal to the tax tribunal.
Statutory review
A statutory review is where someone in a different team who was not involved in the original decision reviews the decision.
- Once HMRC notifies a tax adviser regarding the offer of a statutory review, they will have 30 days to accept the offer.
- An offer cannot be accepted if an appeal has already been made to the tribunal.
- A late request may be allowed if there is a reasonable excuse.
- The statutory review usually takes up to 45 days, but the tax adviser will be notified if it will be longer.
- HMRC will then contact the tax adviser to confirm if their original decision:
- Remains unchanged.
- Has changed.
- Has been cancelled.
- If the tax adviser still disagrees, an application can be made to the tribunal.
Appeal to the tax tribunal
An appeal can be made to the tribunal instead of accepting a statutory review or after its outcome.
Temporary relief
If a tax adviser thinks their business cannot continue to trade while the review is ongoing, 'temporary relief' can be applied for.
This allows tax advisers to continue to interact with HMRC on behalf of clients while the review is being carried out.
Temporary relief can be applied for if the tax adviser is challenging:
- The rejection of an application to register as a tax advisor.
- A decision to suspend a registration.
Further guidance is expected on temporary relief.
Notifying clients
If a tax adviser has received a suspension for more than 30 days or there has been a temporary or permanent ban, clients must be notified within 30 days. Failure to do so may result in a £5,000 penalty for each client that should have been informed.
Useful guides on this topic
Mandatory tax adviser registration with HMRC
From May 2026, all tax advisers who interact with HMRC on behalf of clients will be required to register with them. Who will be required to register? What conditions must be met? What are the consequences of non-compliance with 'mandatory tax adviser registration'?
HMRC's Standards for Agents
Our guide to HMRC's 'Standard for agents', HMRC's approach to tackling bad agent behaviour, and providing a definition of a tax adviser.
HMRC's Customer Charter
This is a freeview 'At a glance' guide to HMRC's Customer Charter. HMRC's Charter sets out what taxpayers can expect from HMRC and what HMRC expect from taxpayers. The latest version was issued in November 2020.
Professional Conduct in Relation to Taxation
The Professional Conduct in Relation to Taxation (PCRT) sets out the ethical and professional standards expected of members of the seven authoring professional bodies when advising on UK tax matters.
External links
What happens if you interact with HMRC when you are unregistered or suspended as a tax adviser
If you disagree with HMRC's decision about your tax adviser registration