SALF205 - Self Assessment tax returns: time limits for Self Assessment procedure
Ordinary time limit of four years
Section 34(1)
The normal time limit for making an assessment is not later than 4 years following the end of the tax year to which it relates. After the 4-year time limit has passed tax can only be assessed by means of an HMRC assessment if the loss of tax was brought about carelessly or deliberately or in other limited circumstances (see SALF411).
Section 34A
The ordinary time limit for making a self assessment in a return made and delivered to HMRC is not more than 4 years following the end of the tax year to which it relates.
In certain exceptional circumstances, the self assessment time limit may be extended where there has been a determination of tax under section 28C (see Time limits for determinations and subsequent self assessments in SALF209).