HM Revenue & Customs (HMRC) has issued an urgent alert about important changes to corporation tax coming in this April.

The changes will require all company tax returns sent in from April 2011 to be filed online, for accounting periods ending after 31 March 2010, in a specified data format (known as Inline XBRL or iXBRL). Corporation tax payments must also be made electronically from April 2011.

As well as limited companies, the changes will affect other organisations that pay corporation tax, including clubs, societies, associations, co-operatives, charities and other unincorporated bodies.

Companies will be able to file online either through commercially available software or by using HMRC’s own filing software, which is aimed at companies with less complex tax affairs.

For more information, visit www.hmrc.gov.uk/efiling/ctsoft_dev.htm.