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HMRC internal manual

Company Taxation Manual

Corporation Tax self-assessment (CTSA): Assessments: Normal due date unaffected


The normal due date for CT is nine months and one day after the end of the accounting period. Nothing in the CTSA rules alter this date.

For accounting periods ending on or after 1 July 1999, however, ‘large’ companies have to pay their tax in instalments (see CTM92500 onwards).