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HMRC internal manual

Excise Assessments Interim Guidance

Best judgement: helpful pointers to a best judgement assessment

Do not

  • pluck a figure from “thin air” or base your judgement on “gut instinct”, or
  • discard any material which you feel is relevant.


  • take care when performing calculations. If the calculation is complex ask a colleague to check it
  • remember, the strongest evidence will always be that which the business agrees with in principle
  • ensure that your assessment is not artificially high in the hope that the business will be forced to provide additional evidence
  • remember that you must be able to demonstrate the credibility of your assessment. Always ask yourself if your projections are within the capabilities of the business.

Finally, remember that you do not have to carry out exhaustive investigations.