SolvedCTM05130 | Corporation tax: restriction on relief for carried-forward losses: deductions allowance for a company not in a group
From HM Revenue & Customs · Company Taxation Manual
If a company is not a member of a group (CTM05160) for any part of a 12 month accounting period, then its non-group deductions allowance for that accounting period is £5 million. If however the accounting period is less than 12 months, this amount is reduced proportionally.
Similarly, if the company’s accounting period begins before and ends after 1 April 2017, which is the commencement date for the loss restriction, then the company’s deductions allowance should be reduced to reflect the proportion of its accounting period that falls on or after 1 April 2017.
The company should specify the amount of its deductions allowance in its tax return (CTA10/S269ZZ), usually as part of the related tax computations.