Tax appeals, disputes and complaints Complaining about poor service

If you have complaint about unreasonable delays on the part of HMRC or a mistake that could have been avoided, use our step-by-step guide to making a formal complaint.


Raise your complaint with the person who has been dealing with your case.

2Put it in writing

If you’re still unhappy with how your complaint is being dealt with, put it in writing to the customer relations/complaints manager. Head the letter or fax COMPLAINT very prominently and explain what has gone wrong and how you’d like it resolved. Include:

  • Your full name, address, telephone number and email address
  • Your National Insurance number
  • The last reference number HMRC used when contacting you
  • Your unique taxpayer reference (UTR) if you are in self-assessment

3Ask for a review

If this is unsuccessful, ask the director with responsibility for the office concerned to review your complaint – your tax office will have details of who this is.

4Go to the independent adjudicator

If the director cannot help, then you can ask the independent adjudicator to look into the complaint within six months of your final correspondence with the director’s office. The service is free.

5Talk to your MP

If you’re still unhappy ask your MP to refer your case to the Parliamentary Ombudsman. You can do this at any time, but the adjudicator won’t look at a complaint if it has been taken up by the ombudsman. In addition, the Ombudsman will generally not consider a tax or tax credits referral until it has been through the Adjudicator.

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