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HMRC internal manual

Inheritance Tax Manual

Calculating the penalty: penalties due on more than one asset

If more than one asset is omitted or undervalued, the circumstances may be such as to warrant different abatements (IHTM36177) for different assets.

When considering the abatements to be applied in arriving at the penalty, consider all the available evidence in respect of each separate asset and decide upon the degree of culpability to be applied to each asset. But in seeking the expected offer (IHTM36174), the penalty should be expressed as a global percentage and an amount for each asset, but, if requested, you should be prepared to indicate how you arrived at the percentage used for each asset.