United Kingdom corporation tax applies to jurisdiction United Kingdom
HM Revenue and Customs powers of enquiry
HMRC has one year from the normal filing date, which is itself one year after the end of the period of account, to open an enquiry into the return. This period is extended if the return is filed late. The enquiry continues until all issues that HMRC wish to enquire about a return are dealt with. However, a company can appeal to the Commissioners of Income Tax to close an enquiry if they feel there is undue delay.If either side disputes the amount of tax that is payable, they may appeal to either the General or Special Commissioners of Income Tax. Appeals on points of law may be made to the High Court (Court of Session in Scotland), then the Court of Appeal, and finally, with leave, to the House of Lords. However, decisions of fact are binding and can only be appealed if no reasonable Commissioner could have made that decision.Once an enquiry is closed, or the time for opening an enquiry has passed, HMRC can only re-open a prior year if they become aware of an issue which they could not reasonably have known about at the time, or in instances of fraud or negligence. In fraud or negligence cases, they can re-open cases from up to 20 years ago. After an HMRC enquiry closes, or after final determination of an issue by the courts, the taxpayer has 30 days to amend their return, and make additional claims and elections, if appropriate, before the assessment becomes final and conclusive. If there is no enquiry, the assessment becomes final and conclusive once the period in which the Revenue may open an enquiry passes.