Taxes Management Act 1970 section 34A

Ordinary time limit for self-assessment

Section 34A establishes the standard time limit within which a self-assessment contained in a personal tax return or a trustee tax return may be made and delivered to HMRC.

• A self-assessment may be made and delivered up to four years after the end of the relevant tax year
• If HMRC issues a notice to file within the four-year window, the taxpayer has at least three months from the date of that notice to respond with a return including a self-assessment
• Where HMRC has made a determination of tax in the absence of a return, the taxpayer may still submit a self-assessment within the time allowed under those determination provisions
• For tax years before 2012-13, the deadline was fixed at 5 April 2017 rather than being calculated as four years from the end of the relevant year