No inheritance tax is payable on gifts between spouses or civil partners as long as both parties are domiciled in the UK. This is often used as a basic method of IHT avoidance. If the gift is a transfer to a foreign domiciled spouse it is only exempt up to £150,000.
Spouses and civil partners can now make full use of the nil rate band belonging to each spouse. That gives a total inheritance tax exemption for a married couple of £650,000. The rules allow any unused part of the nil rate band on the death of the first spouse or civil partner to be passed to the surviving spouse or civil partner for use on their death.
Say Fred died with an estate worth £500,000. If he wasn’t married, his executors will be required pay IHT at 40% on £175,000 (£500,000 – £325,000) amounting to £70,000. If Fred was married, and his wife did not use her nil rate band when she died previously, he now has the benefit of two nil rate bands totaling £650,000. Now Fred’s executors will pay no IHT at all on his estate of £500,000.
The amount of the nil rate band that can be transferred is the proportion of the nil rate band that was unused on the death of the first spouse or civil partner. For example if on the first death, 50% of a 325K nil rate band was unused, if on the second death the nil rate band is 350K at that time, then 50% x £350K = £175K is available for use in addition to their own nil rate band.
There are additional rules where there are more than one deceased spouse or civil partner.