This note offers guidance in respect of the administration of company tax returns. If a company or organisation is subject to corporation tax they will have to complete and file a company tax return for each accounting period. A company or organisation must, in the main, file a return even if they have not made any taxable profits during the accounting period. In this guidance note, 'company' includes entities which are not strictly companies but are within the charge to corporation tax, eg unincorporated associations. For information on which entities are within the charge to corporation tax, see the Charge to corporation tax guidance note.
A company tax return is made up of the company tax return form (form CT600), together with any supplementary pages and other relevant information. For full details of the documents to accompany a tax return, see the Documents to accompany a company tax return guidance note.
Corporation tax self-assessment
It is the responsibility of the company to assess how much corporation tax is due for each accounting period.