Succession: intestacy: distributions in Northern Ireland: bona vacantia
If there are no surviving relatives (IHTM12125) the Crown (which includes the Duchy of Lancaster and the Duchy of Cornwall) in the last resort takes the residuary estate as bona vacantia. For deaths on or after 26 July 1984, by virtue of, FA1984 schedule 21, paragraph 13 (now IHTA1984/S91), the Crown, as residuary beneficiary, is deemed to be entitled to the specific assets of the deceased immediately from the date of death. So, for deaths on or after that date, there is no claim to Inheritance Tax (IHT) as the Crown is immune from taxation. But, the property is still part of the estate on death and its value will be aggregable with any other chargeable property treated for IHT purposes as forming part of that estate - for example, settled property in which the deceased had an interest in possession.
For deaths before 26 July 1984, the general rule of English law, that the right of the residuary beneficiary is not to the specific assets of the deceased, applies. Crown immunity does not apply as the Crown is only entitled to the clear residue when the administration has been completed. In these circumstances liability for IHT rests with the personal representative, who will be the Treasury Solicitor, Solicitor for the Duchy of Lancaster or Solicitor for the Duchy of Cornwall. Calculations of tax should be sent to them in the normal way.