You must tell us that your company exists and that it is liable to tax.

The word 'company' is also used to include:

• members' clubs, societies and associations
• trade associations
• housing associations
• groups of individuals carrying on a business but not as a partnership, (for example, co-operatives.)

What you have to do

For Corporation Tax, companies

• have to work out their own tax liability
• have to pay their tax without prior assessment by the Inland Revenue
  and
• are liable to penalties if they do not deliver a return by the statutory filing date, normally 12 months after the end of the accounting period.

Corporation Tax is due for 'Accounting Periods' which are normally 12 months long. Accounting periods can, in some circumstances be shorter than 12 months but never longer.

For more details and explanations, go to:

• CTSA BK3 A Modern System for Corporation Tax Payments – a guide to quarterly instalment payments (PDF 76K)
• CTSA/BK4 A general guide to Corporation Tax Self Assessment (PDF 157K) or,
• A Guide to Corporation Tax Self Assessment for Tax Practitioners and Inland Revenue Officers (PDF, 256K)