The Nil Rate Band (NRB) is £325,000 per person. Any part of the estate below this threshold is free from Inheritance Tax. Married couples and civil partners can combine their allowances · if one spouse dies without using their NRB, it passes to the survivor, potentially doubling the threshold to £650,000.
The Residence Nil Rate Band (RNRB) is an additional £175,000 available when you leave your main home to direct descendants (children, step-children, grandchildren). Again, married couples can combine, giving up to £350,000 RNRB. The RNRB tapers by £1 for every £2 of estate value above £2 million.
Combined maximum tax-free threshold (married couple passing to children): £1,000,000 (£650,000 NRB + £350,000 RNRB).
IHT rate: 40% on the taxable estate. Reduced to 36% if 10% or more of the net estate is left to charity.