HMRC compliance checks: help and support

Find out about the compliance checks process and the help you or your client (if you're a tax agent) can get, during and after the checks.

About compliance checks

HMRC carry out compliance checks to:

  • make sure you’re paying the right amount of tax at the right time
  • make sure you’re getting the right allowances and tax reliefs
  • discourage tax evasion
  • make sure the tax system is operating fairly

Something may trigger a check. However, HMRC has the right to check whether any tax return is accurate and complete.

Watch a video about what to expect during a compliance check

Watch a video about what to expect during a compliance check.

Watch a video about how compliance checks work

Watch our video on how compliance checks work.

Get authorisation for your tax agent to deal with checks

If you have a tax agent or adviser and want them to deal with us on your behalf, they must have formal authorisation. We’ll deal with them during the check if they already have formal authorisation.

If they do not have formal authorisation, you must apply for temporary authorisation on their behalf so they can deal with your compliance checks.

If you’re an agent

Apply for formal authorisation or temporary authorisation for your client.

Why HMRC carries out checks

Certain things may prompt us to open a compliance check into your tax affairs. These could include:

  • entering figures on a return that appear to be wrong
  • making a large claim for a VAT refund when turnover is low
  • declaring a small amount of tax when turnover is high

We will call or write to you, and your tax agent if you have one, to say what we want to check and why. If you think we should stop the check, you should tell us why.

If we have started a check, you should continue to file your tax returns and pay your taxes if they’re due.

We may open a compliance check into any tax credits claims to make sure you’re getting the right amount of money.

If you’re a tax agent, you can find detailed information about tax credits checks in the HMRC manual.

Helping us with the checks

During the checks we may ask you to:

  • send us any information or documents that we may need
  • meet with us to discuss your tax affairs and records, but you do not have to meet us if you do not want to

If you have business premises or run your business from home, we may ask to visit them to inspect your premises, assets and records. If you think the request is unreasonable or not relevant to the check, let our officer who requested the information know.

If we cannot agree with you about sending the information or documents, we may use legal powers to get them. We’ll do this by sending you an information notice. If you get a notice, you must give us what we’ve asked for, or we may charge you penalties.

You are responsible for giving us accurate information, and if you have a tax agent dealing with us on your behalf, you should make sure they have all the relevant facts.

If you help us with the compliance check, we can:

  • complete it quickly and reduce any inconvenience to you
  • reduce the amount of any penalty you may be charged if we find there’s something wrong

If you’re affected by coronavirus

If you cannot help us with the check because you’re facing difficulties with the impact of coronavirus let our officer dealing with your check know. We will work with you to agree the best way forward taking into account any difficulties you are facing.

If after the checks, we conclude that you owe us tax, but you cannot afford to pay it immediately, contact the HMRC coronavirus (COVID-19) helpline. You can talk to us about payment arrangements that you can afford.

You might be able to get coronavirus (COVID-19) support if you’re working less or not working.

If you need help during the checks

We can help you if you need extra support when dealing with a compliance check.

If you have any health conditions or personal circumstances that may make it difficult for you to deal with the compliance check, let our officer know. They will work with you to put in place any reasonable adjustment needed.

If you need more time, tell us. We may agree to allow extra time if there’s a good reason, for example, if you’re seriously ill or someone close to you has died.

If you need someone to speak to us for you

You can ask someone else to deal with us on your behalf, for example, a friend, relative or an adviser from a voluntary organisation. You’ll need to appoint them to talk to us for you first.

Get independent help from other organisations

You can get help from charities and other organisations if you do not understand something about the compliance checks process.

If you’re struggling with your mental health because of the checks, you might be able to get support from your GP, TaxAid, Mind or Samaritans.

Find out about the different types of checks and what happens during and after the check.

Outcomes of compliance checks

If the check shows there is nothing wrong, we’ll bring it quickly to an end. If our checks show you have overpaid tax, you will be repaid with any interest due added. If you have underpaid tax, you will need to repay this. You will be charged interest and you may receive a penalty.

We may issue an assessment or amend your return to collect any unpaid tax.

You can apply for Alternative Dispute Resolution (ADR) if you do not agree with an HMRC’s decision or with what we’re checking at any time during the checks.

Watch a video about help if you cannot pay your tax bill

Watch a video about help if you cannot pay your tax bill.


You may be charged a penalty if we find something wrong during the check.

We’ll consider how much you cooperated with us when deciding if we can reduce the penalty. In general, the more help you give, the lower the penalty will be.

Find out what you can do to reduce any penalty we may charge.

If you’re an agent, find out more about penalties.

Watch a video about why we charge penalties and what you can do about them

Watch our video on penalties and what you can do about them.

Criminal investigation

It’s HMRC’s policy to deal with fraud using civil investigation procedures, wherever appropriate.

We reserve criminal investigation for cases where we need to send a strong deterrent message or where the conduct involved is such that only a criminal sanction is appropriate.

Find out more about our criminal investigation policy.

If you disagree with the outcome of the check

If we make a decision you can appeal against, we’ll write to you about the decision and tell you what to do if you disagree.

You will usually have 3 options. Within 30 days, you can:

  • send new information to the officer dealing with the check and ask them to take it into account
  • have your case reviewed by an officer who has not been involved in the matter
  • arrange for an independent tribunal to hear your appeal and decide the matter

Watch a video about what to do if you disagree with an HMRC decision

Watch a video about what to do if you disagree with an HMRC decision.

Contact HMRC

If you need to speak to us about your compliance checks, contact the officer who’s dealing with your case. You can find their details on the letter we sent you about the checks.

You can also contact us to get help with your taxes or to make a complaint.

Published 5 March 2021
Last updated 18 June 2021 + show all updates
  1. YouTube videos about 'what to expect during a compliance check', 'how they work', 'penalties', 'if you disagree with an HMRC decision', and 'if you cannot pay your tax bill' have been added.

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