Inheritance tax

[ididntsignupforthis1]

Anyone know about it?
Mums house worth approx 450k
I will inherit - is it the difference between this and 325k I pay on?
As it was hers and my dad's before he died then does it increase
The rules are confusing me!

Both of parents have a 325k allowance -even dead ones - so it adds up to potentially 650k in total depending on what the threshold was when your dad died. I can't remember the full ins and out but 8 years ago when my dad died we were allowed to add in a proportion from our mums allowance pro rata and she had died 15 years previously.

Sorry I mean both parents have there own threshold which was/is in force when they die/d. So potentially 650k if recent .

Is the inheritance likely to be imminent, if that's not too insensitive a question?

Its hard to say how imminent. She's 90 and has copd.
Dad died in 1993 and everything was left to her so I don't think any of his allowance is used. Didn't know if the 'allowance ' passes over automatically or is something they had to set up legally?
We are going to be looking at poa for financial soon as she's housebound and starting to get confused

It is just automatic and if your dad just passed everything to your mum the full 650k kicks in when mum eventually dies. I also read that from April 2017 the main residence of the deceased attracts a further 100k threshold.

Well according to this page on the HMRC website the applicable threshold in 1993 was £150,000 so if the value of the house is the only item of any value in the estate there could be no tax at all.

The threshold was 150000 in 1993 but they work out what percentage was used by the person that died (say it was 15000 which is 10%) and They then take 10% off the 325000 so 32500 off current threshold. If oP's dad didnt use any of his allowance then his would be the full 325k as of now