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HMRC internal manual

Compliance Handbook

Penalties for inaccuracies: how to process the penalty: supplementary penalties

You must check the date from which these rules apply for the tax or duty you are dealing with. See CH81011 for full details.

Where we have assessed a penalty but the potential lost revenue (PLR) has been underestimated, we may assess a supplementary penalty based on the additional PLR. This allows you to increase the original penalty.

For example

We assessed a penalty for a long list of careless inaccuracies. In compiling the list to get to the total PLR we wrongly missed an amount out of the PLR. The wrong figure is discovered after three weeks. We can make a further assessment of the omitted PLR and the related penalty.

The time limits for issuing a supplementary penalty assessment are as set out in CH83040 but run from the date of the supplementary assessment to recover the further PLR.

FA07/SCH24/PARA13 (6)