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HMRC internal manual

Self Assessment: the legal framework

Payment of tax: automatic interest and late payment penalties: surcharges on tax charged in an assessment for 1995-96 (or earlier) made after 6 April 1998

FA95/S109 (2)

The surcharge rules apply to any income tax or capital gains tax assessment for 1995-96, or earlier, (before the introduction of self assessment) made after 6 April 1998.