Submitting your Company Tax Return

If your company or organisation is liable for Corporation Tax you'll have to deliver a Company Tax Return to HM Revenue & Customs (HMRC) for each accounting period.

This guide explains what you need to deliver with your Company Tax Return form, how to submit your return and what happens once you've done so.

It also explains the requirement to complete and deliver your return online from 1 April 2011.

On this page:

Submitting your Company Tax Return online

You must submit your Company Tax Return online for accounting periods ending after 31 March 2010. You must also pay any Corporation Tax that's due electronically.

Additionally, your tax computations and, with very few exceptions, the accounts that form part of your Company Tax Return, must be submitted in Inline eXtensible Business Reporting Language (iXBRL) format.

In very limited circumstances you may not have to submit an online Company Tax Return and HMRC may accept a paper return instead. These include:

  • if the directors/company officers are all practising members of a religious society or order whose beliefs are incompatible with the use of electronic methods of communication
  • in particular situations involving insolvency - for example where your company or organisation is subject to a 'winding-up order', is in administrative receivership, or is being managed by an administrator

Follow the link below to find out more about online filing and the few companies that may be exempt from this requirement.

Switching from paper to online returns and paying electronically

Top

What you need to deliver with your Company Tax Return form

A complete Company Tax Return isn't just your return form CT600 and your declaration at the end of it. As part of your Company Tax Return, you normally need to deliver:

  • Company accounts (sometimes known as statutory accounts) - these are the accounts your company must file at Companies House or your organisation must prepare under its constitution. They include director's reports and auditor's reports. If your company chooses to file abbreviated accounts at Companies House, you must still file full statutory accounts as part of your Company Tax Return..
  • Separate computations and/or calculations - for example, if you fill in Boxes 3, 16, 17, 43 to 62, 64, 105 to 121 or 131 you need to include a computation as part of your online return showing how you worked out those figures.

Additional documentation you may also need to deliver as part of your return, depending on the particular circumstances of your company or organisation, includes:

  • The online equivalent of supplementary pages:
    • Loans to Participators by Close Companies - directors' loans (form CT600A)
    • Controlled Foreign Companies (form CT600B)
    • Group and Consortium (form CT600C)
    • Insurance (form CT600D)
    • Charities and Community Amateur Sports Clubs (CASCs) (form CT600E)
    • Tonnage Tax (form CT600F)
    • Corporate Venturing Scheme (form CT600G)
    • Cross-Border Royalties (form CT600H)
    • Supplementary charge in respect of ring fence trades (form CT600I)
    • Disclosure of tax avoidance schemes (form CT600J)
  • Any other relevant claims, elections, reports or statements.

Top

What happens after you deliver your Company Tax Return?

Online returns - what counts as the date received?

As soon as the HMRC computer system receives your online return, this is automatically recorded as the date received.

Some simple checks are done automatically and then HMRC will review your online return to make sure that it's complete.

Returns delivered by post or in person - what counts as the date received?

Please note: this guidance only applies if your company or organisation is exempt from submitting their Company Tax Return online (see above).

HMRC considers a return sent by post, or delivered in person, as delivered when it's physically handed over to HMRC office staff, or placed in an HMRC office letterbox during working hours. This is particularly important to consider if you intend to deliver your return close to your company or organisation's filing date and wish to avoid unnecessary late filing penalties.

To avoid delays and unnecessary penalties, you should send your return to the office that issued your 'Notice to deliver a Company Tax Return'.

HMRC will update their computer system to show your return has been received, normally on the day of receipt or as soon as possible afterwards. They'll also carry out some basic checks to make sure that your return is complete (for example, they'll check that the declaration is signed and that you've attached your company accounts). HMRC will then ensure that the information shown in your return is recorded or 'captured' onto the relevant computer systems.

If there are any problems with your return (or attachments) HMRC may send the return back to you for further action.

Correcting errors and making changes

Within certain time limits, you can change (or amend) a return you've already delivered to HMRC.

How to change a Company Tax Return you've already filed

HMRC can correct simple, obvious errors or omissions in your Company Tax Return, (or amendment) and any accompanying computations and claims. But they can only make a correction up to nine months from the date you filed your return, or made your amendment or claim.

What to do if you don't agree with an HMRC correction

If HMRC want to ask more about any of the entries on your return they'll need to 'make an enquiry' or carry out a 'compliance check'.

If HMRC does this it doesn't necessarily mean that they think your return is incorrect. They may just need more information.

HMRC compliance checks and enquiries for Corporation Tax

Top

More useful links

Completing your Company Tax Return form

Corporation Tax forms

See a demonstration of how you can manage your Corporation Tax account online

Corporation Tax glossary

Top