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HMRC internal manual

COTAX Manual

Penalties: penalty determinations: return periods

Companies incur penalties for failing to deliver a return or returns in response to a notice to deliver.

You may not be certain of the return period or periods when you determine the penalties. However, when the specified period in a notice to deliver is for 12 months, the notice always requires the delivery of at least one return.

Late filing penalties are determined by reference to the obligation imposed by a notice to deliver without specifying the return period or periods involved.

This means that determinations are not invalid if your assumptions about the return period or periods turn out to be incorrect.

See COM101011 for legislation applying to this subject.