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HMRC internal manual

Self Assessment Claims Manual

Overpayment relief: Commencement

From 1 April 2010, persons may claim overpayment relief for any period provided that they are within time to do so.

There are transitional rules for certain overpayment relief claims for the years 2004-05 and 2005-06, see SACM12180.

Also from 1 April 2010

* individuals and partnerships can no longer claim error or mistake relief in respect of any tax year, and
* companies cannot claim mistake relief for any accounting period.

If a person claimed error or mistake relief (for individuals and partnerships) or mistake relief (for companies) before 1 April 2010, we deal with their claim under the old rules, see SACM12200, and they cannot subsequently claim overpayment relief in respect of the same mistake.

If a person meets all the conditions for overpayment relief, we will not deny the relief just because they might have been able to claim under the old rules but did not.

Section 100(2) Finance Act 2009