Nil Rate Band Carryforward
Visit the Taxes screen, on the People panel, right, select the name of the person who is to receive the transferred nil rate band.
Important Note: if that person already has an entry in the Taxes screen, you will need to select their existing entry from the Ledger to edit. If you try to create a new entry for someone who already has a Taxes item, an error will appear.
Expand IHT Exemption / Nil Rate Band Carry Forward and set the Percent of IHT Nil Rate Band carried forward to 100%, and the Percent of Residence Nil Rate Band carried forward to 100%, if applicable, (or the relevant percentages).
Click Add or Update.