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HMRC internal manual

Self Assessment Claims Manual

Appendix 1: Old Error or Mistake Relief: Repayment Supplement

From 1 April 2010, it is not possible to make a claim for the old error or mistake relief for any period. The relief is replaced by overpayment relief, see SACM12000+. You will only need the guidance in SACM Appendix 1 if you are dealing with a claim made before 1 April 2010.

Repayment supplement (see RE manual) is due on the net error or mistake relief available after taking into account any liability arising on other sources or in other years as a consequence of the claim - see SACM20060.