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What is an HMRC compliance check?

Answered 17 March 2026

HMRC Guidance / Practice

An HMRC compliance check (sometimes also known as a 'tax enquiry') is when HMRC checks your tax position.

Why HMRC carries out compliance checks

HMRC carries 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

What a compliance check involves

By its very nature, a compliance check can be intrusive and an unwelcome distraction for the taxpayer, sometimes over a lengthy period of time. Many parts of HMRC are involved in compliance checks of one sort or another.

A compliance check into a return can extend to anything in the return, or anything required to be contained in the return. The compliance check notice will usually specify the matters being enquired into, but this is not obligatory.

Rights and obligations

It is important that everyone understands their rights and obligations when they are the subject of an HMRC compliance check. Explaining these rights and obligations, the purpose of the check, and how it will be done should mean that the check can be completed more quickly and efficiently.

HMRC must give the person an appropriate general information factsheet (e.g. CC/FS1a) at the start of every compliance check, which includes important information about penalty reductions for disclosure.

Triggering a compliance check

Where insufficient information is included in a tax return, this can lead to HMRC having difficulty understanding what is being returned, which can result in compliance checks being opened to verify figures or understand adjustments.

Limits on compliance checks

HMRC cannot open a compliance check into a return if a compliance check has previously been opened into that return, except where an amendment to the return is made — in which case a check can be opened in relation to the amendment. A discovery assessment for the period may still be made.


Citation sources

1 GUIDANCE
HMRC compliance checks: help and support

A compliance check (sometimes known as a ‘tax enquiry’) is when HMRC checks your tax position. We 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 You can read this guidance to get help and support during the compliance check process. You can also get help and support using our online tool.

HMRC guidance
2 MANUAL
Mistakes: Compliance checks: general

Many parts of HMRC are involved in compliance checks of one sort or another. See Compliance Handbook CH201100 (external users can find the guidance at http://www.hmrc.gov.uk/manuals/chmanual/ch201100) for further information. But no matter what the area of compliance, we approach complaints handling and remedy in the same way in all our work. It is not the role of complaints policy or procedures to consider matters which are proper to the tribunals. Many disputes in the context of a compliance c

HMRC guidance
3 MANUAL
Notice and Scope of a Compliance Check

A compliance check into a return can extend to anything in the return, or anything required to be contained in the return. If the compliance check is due to an amendment to the DST return, the scope of the compliance check is limited to matters relating to or affected by that amendment. This is unless the compliance check window for the original return is still open. HMRC do not have to give reasons for dissatisfaction with the return and should not do so. HMRC cannot open a compliance check if

HMRC guidance
4 MANUAL
Carried interest: information provided in a tax return

Individuals are required to account for the UK tax they owe, and if HMRC suspects the right amount of tax has not been returned, HMRC can open enquiries into individuals’ tax returns. Where insufficient information is included in a tax return, this can lead to HMRC having difficulty understanding what is being returned. This can result in compliance checks being opened to verify figures or understand adjustments. When an individual does not have access to information required to complete the com

HMRC guidance
5 MANUAL
Administration: Compliance: Compliance checks: Notice and scope

A compliance check into a return can extend to anything in the return, or anything required to be contained in the return. This includes anything related to the amount of MTT chargeable and whether MTT was chargeable in the period. The compliance check notice will usually specify the matters being enquired into, but this is not obligatory. Where the matters are specified in the compliance check notice, this does not prevent HMRC from including other matters in the compliance check. If the compli

HMRC guidance
6 MANUAL
How to do a compliance check: starting a compliance check: introduction

This page and chapter are under review as the relevant content is also published in the technical guidance chapters of the Compliance Handbook, within Compliance checks factsheets and in Compliance checks guidance. If you use particular pages regularly, please email hmrcmanualsteam@hmrc.gov.uk to let us know the specific content you find useful. It is important that everyone understands their rights and obligations when they are the subject of an HMRC compliance check. Explaining these rights a

HMRC guidance