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HMRC internal manual

Inheritance Tax Manual

Disclosure: additional abatement

You may allow the extra 10% abatement where there is spontaneous and complete disclosure.This may have the effect of reducing the penalty loading to nil where, for example thereis full co-operation (IHTM36191) and the gravity (IHTM36201) of the offence is not too serious.


In an enquiry where, following a spontaneous disclosure, the extra 10% is given, co-operation is full and complete and you decide to allow a 30% abatement out of the 40%allocated to the gravity of the offence, the net loading will be as follows

Penalty   100%
Less abatements    


Gravity 30%


  Net penalty loading   0%

This is something you will need to consider when you carry out your risk assessment (IHTM36144) of the potential penalty.