Section 663: Contracts to which section 641 applies
1837.This section provides that, if a company makes a claim, allowable losses deemed to arise for an accounting period may be carried back and set against chargeable gains deemed to arise in accounting periods in the previous 24 months. It is based on paragraph 45B(1), (2) and (3) of Schedule 26 to FA 2002.
1838.The gains and losses deemed to arise are those given by section 641 (chargeable gains basis substituted for income basis in charging credits and debits from certain types of derivative contract).
1839.The gains eligible for relief in an earlier period are the total section 641 gains for that period less the total of allowable losses under that section for that period. Those gains are further reduced by any other allowable losses for that period so far as those other allowable losses could not be deducted, within the meaning of section 8(1) of TCGA, from other chargeable gains. That is, any allowable losses for the purposes of corporation tax on chargeable gains, other than losses under section 641, are notionally deducted from the section 641 gains if they cannot be set against any chargeable gains, other than gains under section 641, to find the amount of gains against which the losses carried back under this section can be set. The amount found under this rule is called “net section 641 gains”.
1840.Subsection (3) provides that, to the extent the losses for a period are carried back and relieved under this section, they are used up and cannot otherwise be relieved under the provisions for corporation tax on chargeable gains by set off or carry forward.