For periods before the start of self assessment HMRC could issue an assessment at any time up to six years after the end of the chargeable period to which the assessment related. There is no limit in cases of fraud or wilful default. All business records must be retained for a period of (broadly) six years.

As a general rule, HMRC can raise an enquiry into a self assessment tax return within 12 months of the date the return was submitted. Where an incomplete return has been made, they can issue an assessment at any time up to four years after the end of the chargeable period to which the assessment related. Where the loss of tax is due to carelessness, the time limit is extended to six years. There is a limit of 20 years in cases of fraud or wilful default. Under normal circumstances, all business records must be retained for a period of (broadly) six years.

Under corporation tax self assessment, accounting records must be preserved for six years from the end of the accounting period.

With regard to the statutory books, the Companies Act states they must be retained for 10 years.

The 1980 Act allows an action to be brought on a contract for up to six years from the event (e.g. breach) that gave rise to the claim.

Where a contract is under seal (or deed), the time limit is twelve years.

These periods govern how long invoices and other documents should be retained as evidence in case of a claim by, or against, another party.