Online Services – Corporation Tax Online

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Accounting periods ending after 31 March 2008

Announcements in the Chancellor's Budget in March 2008 mean that the company tax return form (CT600) needs updating. The CT600 Budget Insert (April 2008) gives advice and lists the main changes including those that affect the return form CT600.

The changes to the rates of corporation tax on profits affect the tax calculations of most companies as the main and small companies’ rates and marginal small companies’ relief fraction used from 1 April 2008 have all changed. We have planned for Corporation Tax Online services to handle returns using the new rates from 1 June 2008.

We advise companies affected by these rate changes not to use Corporation Tax Online services before then. If a company needs to deliver a return before then for a period that ends after 31 March 2008 and that return includes calculations based on the new rates it can still deliver a paper return direct to its HM Revenue & Customs office provided it follows the advice given in the CT600 Budget Insert April 2008 (PDF 81K).

There are also changes to capital allowances for expenditure after 31 March 2008, including a new annual investment allowance and the introduction of a first-year tax credit. Claims cannot be made until after the Finance Bill has received Royal Assent and we have planned for both Corporation Tax Online services and paper returns to handle these new capital allowances from October 2008.