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HMRC internal manual

Company Taxation Manual

CTSA: the filing obligation: filing date: Companies Act extension

FA98/SCH18/PARA19 (formerly TMA70/S94 (3))

A company granted further time by the Registrar of Companies in which to deliver its accounts, may be able to deliver its return later than the filing date without incurring a penalty.

There are more details at CTM94100 onwards.