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HMRC internal manual

Tax Credits Technical Manual

Statutory Interest: Penalties

A Section 31 or 32 penalty carries interest from the date on which it becomes due and payable. Where a formal penalty determination is issued this is 30 days from the date on which the claimant receives the notice of the penalty determination. For example, if the notice is received on 1 May 2011 the penalty must be paid by 31 May 2011 otherwise interest will be automatically charged.