As readers will be aware, the March 2012 Budget announced changes to Corporation Tax rates and allowances from April 2012 including reductions in the main rate of Corporation Tax from 26% to 24% with the small profits rate remaining at 20% per cent.

The rate changes affect returns with accounting periods ending on or after 1 April 2012 with filing dates of 1 April 2013 or later. These changes took effect on 17 July 2012 when Finance Bill 2012 received Royal Assent.

HMRC advise that as a result the Corporation Tax online service has been updated with the new rates and can now be used to file all Company Tax Returns. If a company is liable at the main rate and intends to use HMRC's free online filing software to submit a return for an accounting period ending on or after 1 April 2012, it will be therefore be necessary to download the latest version of the form as earlier versions don't include the new rates.

HMRC have also published a new guide to completing the Form CT600 (Company Tax Return)