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HMRC internal manual

Self Assessment Claims Manual

Overpayment relief: Error or mistake relief claims no longer possible

Overpayment relief replaces the old error or mistake rules for individuals, partnerships and companies.

From 1 April 2010, it is not possible to make a claim for the old error or mistake relief for any period.

If, exceptionally, you need to refer to the old guidance for error or mistake relief see SACMApp1.