How HMRC works with large businesses

Find out what HMRC’s Large Business Directorate does and how to contact them.

HMRC’s Large Business Directorate works with around 2,000 of the UK’s largest businesses to make sure they pay the correct amount of tax.

The directorate works with most businesses in the UK who have an annual turnover of more than £200 million.

We also work with businesses who have an annual turnover below £200 million if either the:

  • business is complex
  • sector in which the business operates is complex – this is to make sure everyone in the sector is treated the same

HMRC’s approach to large business tax compliance

We take a risk-based approach when we work with all our customers, including large businesses.

With large businesses, the amount of money involved and the complexity of the tax affairs means we begin to take a more resource-intensive approach.

We are investigating the tax affairs of around half of the UK’s largest businesses at any one time.

We work with the highest-risk businesses at board level through our High-Risk Corporates Programme.

Customer Compliance Managers

We assign a senior professional called a Customer Compliance Manager (CCM) to each of the UK’s largest businesses.

The primary role of a Customer Compliance Manager is to make sure your business pays the correct amount of tax, at the right time.

Customer Compliance Managers are supported by:

  • specialists for all tax regimes
  • data analysts
  • solicitors
  • audit specialists
  • trade sector experts
  • forensic accountants

How to contact HMRC’s Large Business directorate

Contact your Customer Compliance Manager if you’re a large business with a technical question.

Use this list of email address to contact us if you have a general, non-technical query.

You’ll need your 3-digit tax office code number to find the correct email address. You can find this number on all the correspondence from your Corporation Tax office.

Tax office code number Email address

More information

You can find statistics about the outcome of HMRC’s large business compliance work on GOV.UK.

Published 12 November 2014
Last updated 2 July 2021 + show all updates
  1. Updated Introduction text. More information section added.

  2. Updated with the latest information on the role of HMRC Large Business, and how to contact them.

  3. First published.