All UK company tax returns filed from April 2011, which cover the accounting period ending after 31 March, 2010, will have to be filed online using the Inline XBRL (iXBRL) data format. XBRL stands for eXtensible Business Reporting Language. It refers to a way of tagging financial data so it can be automatically processed by software systems. Inline XBRL makes XBRL readable by humans — guaranteeing the layout and presentation of data looks the same for both the author and the person receiving it.

Last week, exchequer secretary David Gauke said HM Revenue & Customs (HMRC) was willing to accept technical problems as a reason for late iXBRL filing. "HMRC has confirmed that if a deadline is missed because of implementation issues with iXBRL software, their well-established reasonable excuse provisions will apply," he said in a written answer to parliament.

For more on this ZDNet UK-selected story, see iXBRL filings: Taxman to spare the rod on