CTM90610 | Corporation tax self-assessment (CTSA): Claims and elections: Time limits
From HM Revenue & Customs · Company Taxation Manual
The general time limit for making a claim for relief is four years from the end of the accounting period to which the claim relates ().
However, any specific time limit applying for a particular claim over-rides this general time limit.
The accounting period to which a claim “relates” is the period in which the event giving rise to the claim occurs.
Example
A Ltd has a trading loss for the accounting period ended 31 December 2019 and claims under to set it off against profits for the accounting period ended 31 December 2018.
The claim relates to the accounting period ended 31 December 2019 in which the loss occurred. contains a specific time limit to make the claim “within the period of two years after the end of the loss-making period”, which overrides the general time limit in .
The company must make the loss relief claim by 31 December 2021.