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HMRC internal manual

Company Taxation Manual

ACT: set-off against CT on profits: repayment from carry-back of surplus

The carry-back of surplus ACT under ICTA88/S239 (3) could result in a repayment of CT. Repayment supplement or repayment interest was calculated as if that repayment were being made for the accounting period in which the surplus ACT arose, and not for the accounting period against the liability of which the surplus ACT was actually set-off (ICTA88/S825(4) and ICTA88/S826 (7)).

Correct calculation of repayment supplement or repayment interest depended on appropriate instructions being given to identify repayments requiring special treatment - see CTM20220 and CTM92250.