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HMRC internal manual

Customs Civil Penalties Guidance

Warning letter: considering whether to issue a warning letter: Customs Penalty Action Checklist

You must complete a Customs Penalty Action Checklist (CPAC) to consider whether a Civil Penalty Warning Letter (CPWL) is the appropriate course of action.

The template is on SEES.

There is further guidance at CCPG26230 - CCPG26290 about the questions within the CPAC.