674. Errors or mistakes in returns; individuals.

If:

  1.  

    (1)     a person has paid an amount by way of income tax or capital gains tax1 but the person believes that the tax was not due; or

  2.  

    (2)     a person has been assessed2 as liable to pay an amount by way of income tax or capital gains tax, or there has been a determination or direction to that effect, but the person believes that the tax is not due,

the person may make a claim to the Commissioners for HM Revenue and Customs for repayment or discharge of the amount3. Such a claim may not be made more than