How to find out if dad's IHT allowance passed to mum?

bicyclist

Bit confused by this... Dad passed 10 years ago. I don't believe he used much (if any) of his IHT allowance when everything passed to mum. Now mum has passed. Property value is 325k, but including everything else will put us just over 500k (by about 20k). How do I find out if mum received any of his IHT allowance (as IHT needs to be paid before I can apply for probate)? Thanks.

p00hsticks

Assuming he died in England or Wales...
If he left everything to your mother and they were married then she'll have inherited all of his NRB allowance. 

bicyclist

p00hsticks said:

Assuming he died in England or Wales...
If he left everything to your mother and they were married then she'll have inherited all of his NRB allowance. 

I see. Thanks!

Keep_pedalling

Everything passing to a surviving spouse is covered by spousal exemption so provided they were married or in a civil partnership none of his nil rate band (NRB) will have been used.

On the assumption that they were married, avoid using your mother’s residential NRB as this will require you to do a full IHT return. Using her standard NRB and the transferable NRB from your father will give you total exemptions of £650k and only requires you to submit a probate application.