Taxes Management Act 1970

91 Effect on interest of reliefs

(1) Where any amount of interest is payable under section 86 or section 88 of this Act in relation to an assessment, and relief from tax charged by the assessment is given to any person by a discharge of any of that tax, such adjustment shall be made of the said amount, and such repayment shall be made of any amounts previously paid under those provisions in relation to the assessment, as are necessary to secure that the total sum, if any, paid or payable under those provisions in relation to the assessment is the same as it would have been if the tax discharged had never been charged.

(2) Where relief from tax paid for any chargeable period is given to any person by repayment, he shall be entitled to require that the amount repaid shall be treated for the purposes of this section, so far as it will go, as if it were a discharge of the tax charged on him (whether alone or together with other persons) by or by virtue of any assessment for or relating to the same chargeable period, so, however, that it shall not be applied to any assessment made after the relief was given and that it shall not be applied to more than one assessment so as to reduce, without extinguishing, the amount of tax charged thereby.

(3) Notwithstanding anything in the preceding provisions of this section, no relief, whether given by way of discharge or repayment, shall be treated for the purposes of this section as—

(a) affecting tax charged by any assessment to surtax unless it is a relief from surtax, or

(b) affecting tax charged by any assessment to income tax made under Schedule A or Schedule D if either—

(i) it is a relief from surtax, or

(ii) it arises in connection with income taxable otherwise than under Schedule A or Schedule D, or

(iii) it relates to a source income from which is taxable otherwise than under Schedule A or Schedule D.

(4) For the purposes of this section a relief from corporation tax or capital gains tax shall not be treated as affecting tax charged by any assessment unless the assessment is to the same tax.