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HMRC internal manual

Self Assessment: the legal framework

Other issues: assessment, employees, trustees, personal representatives and beneficiaries of estates: time limits

Under the self assessment regime, before 1 April 2010, all general time limits were determinedby reference to the 31 January following the tax year to which the tax return, claim etc related.

From 1 April 2010, most time limits run by reference to the end of the tax year.