how long keep self assessment records
You should keep business tax records relating to a particular tax year for at least five years after that yearâs tax return deadline (31 January following the end of the tax year).For example, suppose you have chosen the calendar year (to 31 December) as the accounting period used for working out your annual profits.he tax return deadline is 31 January 2013 and the tax records should be kept until at least 31 January 2018. Non-business tax records should be kept for at least a year after the tax deadline. If you file your tax return late, the tax records should be kept for at least 15 months after the date of filing.