If your company or organisation is liable for Corporation Tax you'll have to file a Company Tax Return for each accounting period. Generally, you must file a return even if your company or organisation hasn't made any taxable profits. This guide explains what a Company Tax Return is, how you will be required to provide your return information to HMRC and provides links to more detailed guidance, should you need it.
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A complete Company Tax Return is typically made up of a number of items:
You may also need to submit additional items as part of your return. These will depend on the particular circumstances of your company or organisation. These include:
With some exceptions, the accounts and computations attached to a return must be in a set format - Inline eXtensible Business Reporting Language (iXBRL). iXBRL is an IT standard designed specifically for business financial reporting - not just tax filing. But don't worry, you don't have to be an IT expert to file online, your software will do most of the work for you.
All companies that are required to file a return form CT600 online must file their accounts and computations in iXBRL.
All unincorporated charities, clubs and societies that are required to file a return form CT600 must file their computations iXBRL. However, they can choose to file their accounts in either iXBRL or Portable Document Format (PDF).
You can only include one iXBRL accounts file as part of your online Company Tax Return. Any additional accounts forming part of the return must be attached as PDF files.
If you have any other information that you need to include as part of your Company Tax Return - for example, claims or elections, reports or statements - you can attach these to your online return as a PDF.
The maximum combined size for attachments when using the free HMRC software is 5MB.
If you're using commercial software and will be attaching files, please check with your supplier that the product is compatible with the Corporation Tax online service.