Guidance

Company Tax Return obligations

Find out about making a Company Tax Return, what you need to include and who needs to submit a return.

What is a Company Tax Return

A Company Tax Return is made up of:

  • the form CT600
  • any supplementary pages
  • company accounts and tax computations

The Company Taxation Manual CTM93090: delivery of return: content gives more information about what to include in a Company Tax Return.

Who needs to submit a return

If HMRC issues you a notice to deliver a Company Tax Return then you have a legal obligation to submit a return. For this purpose, a company includes:

  • members’ clubs
  • associations
  • societies and other unincorporated bodies

The Company Taxation Manual CTM40000: particular bodies gives more information about what is considered a company for Corporation Tax purposes.

Corporation Tax accounting periods

You must make a Company Tax Return for the company’s accounting period that is the same as (or ends in) the period given in your notice to deliver a return. Read Accounting periods for Corporation Tax for more information.

If the company’s accounting period is different to this, the Company Taxation Manual CTM93020: specified and return periods explains the period or periods for which you must make your return.

When to submit a Company Tax Return

The deadline for your return is 12 months after the end of the accounting period it covers. The Company Taxation Manual CTM93030: filing date: definition gives detailed guidance on return deadlines.

If you miss the deadline you’ll have to pay a penalty for late filing. Read Corporation Tax penalties for more information.

The return declaration

The person making the return must include a declaration that it is correct and complete to the best of their knowledge and belief. If:

  • the company completes and submits its own return, the declaration must be completed by the person making it on behalf of the company
  • a tax agent completes and submits the return on behalf of the company, the declaration must be completed by that agent
  • a tax agent only submits the return on behalf of the company, the declaration must be made by the proper officer or other person authorised to act for the company

Before an agent submits the return, they must:

  • make a copy of the information
  • receive confirmation from the proper officer or other person authorised to act for the company that the information is correct and complete to the best of that person’s knowledge and belief

Providing false information or concealing any part of the company’s profits or tax payable can lead to prosecution of both you and the company.

You can be also charged a penalty if your return is inaccurate. Read Corporation Tax penalties for more information.

Submitting your return to HMRC

Company returns must be filed electronically for any accounting period ending after 31 March 2010. A company or agent must register with HMRC before they can file a return. Read Register for Corporation Tax for more information.

Format

The computations and accounts must be in Inline eXtensible Business Reporting Language (iXBRL). You can use:

This service automatically converts accounts to the required format (iXBRL). It is not available to all companies, but you can check if you can use the Corporation Tax online service.

Exemptions from online filing

The Company Taxation Manual COM60040: CT online filing explains who is exempt from online filing. In these cases you can download and print a copy of the Company Tax Return form CT600.

What happens next

When you submit your online return to HMRC you will receive an acknowledgment of receipt. The acknowledgment does not mean that HMRC has agreed the figures provided in the return. HMRC can amend the return to correct obvious errors or omissions or anything else that they have reason to believe is incorrect. HMRC can also enquire into the return.

How to amend a Company Tax Return after submission

If you discover an error after you’ve submitted your return, tell HMRC promptly, otherwise you may be charged a penalty. Read Corporation Tax: penalties for more information.

You must usually make changes to your return within 12 months of the filing deadline. Read Company Tax Returns for more information.

Paying Corporation Tax

You must pay your Corporation Tax and and any related amounts electronically, you can do this using HMRC’s Pay your Corporation Tax Bill service.

The deadline for paying your Corporation Tax bill is before the deadline for filing your Company Tax Return. It should usually be paid 9 months and 1 day after the end of your accounting period.

Updates to this page

Published 30 September 2022

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