Claims must be made within 4 years after the end of the relevant tax year or accounting period. The relevant tax year or accounting period is

• the one to which the return relates where the overpayment relief claim is on the grounds that the tax liability is excessive by reason of a mistake in a return
• the one to which the assessment, determination or direction relates where the overpayment relief claim is on the grounds that there is an excessive assessment, determination or direction
• the one in respect of which the amount was paid where the overpayment relief claim relates to any other overpayment of tax.

A tax liability may be excessive by reason of a mistake in a return for an earlier period if a figure is final for all periods when that return can no longer be amended. This applies to figures required in corporation tax returns – see CTM04150. When a loss is stated in a company tax return and the return can no longer be amended, the loss becomes final. If the loss is carried forward the tax liability in the return for later accounting period may be higher by reason of a mistake in the return in the earlier period. The time limit is then 4 years after the end of the earlier accounting period in which the error was made. The OPR claim will be subject to the outlined exclusions at S51A FA98 – see SACM12057.

Where we close an enquiry and amend a self-assessment or make a discovery assessment, a person may be able to make consequential claims that would otherwise be out of time, see SACM9005 for income tax and CTM90650 for corporation tax. The person may be able to make overpayment relief claims but only if and to the extent that this affects the additional amount payable as a result of the amendment or discovery assessment.

Para 3 Schedule 1AB TMA 1970

Para 51B Schedule 18 FA 1998

Section 43A(2B) TMA 1970

Para 62(1A) Schedule 18 FA 1998

Para 31 Schedule 1 FA 2010