(1) Except where otherwise provided by the Tax Acts, the amount of any income shall for the purposes of corporation tax be computed in accordance with income tax principles, all questions as to the amounts which are or are not to be taken into account as income, or in computing income, or charged to tax as a person's income, or as to the time when any such amount is to be treated as arising, being determined in accordance with income tax law and practice as if accounting periods were years of assessment.

(2) For the purposes of this section, "income tax law", in relation to any accounting period, means the law applying to the charge on individuals of income tax for the year of assessment in which that accounting period ends, but does not include such of the enactments of the Income Tax Acts so applying as make special provision for individuals in relation to matters referred to in subsection (1).

(3) Accordingly, for the purposes of corporation tax, income shall be computed and the assessment shall be made under the like Schedules and Cases as apply for the purposes of income tax, and in accordance with the provisions applicable to those Schedules and Cases, but (subject to the Corporation Tax Acts) the amounts so computed for several sources of income, if more than one, together with any amounts to be included in respect of chargeable gains, shall be aggregated to arrive at the total profits.