If a spouse has 650000 pounds and decides to leave 500k of this to his son after his death, would tax be payable on this?
Assuming the spouse has not been married before then the spouse has a nil rate band of £325,000 (assuming no lifetime gifts). Thus, the excess of £650,000 over £325,000 (ie £325,000) subject to IHT at 40%.
If instead he left it all to his wife there would be no tax payable is that correct?