Working out inheritance tax and what to report to HMRC

[Strats]

Hi all,

thanks in advance for any help or guidance that may be provided.

My Grandad has recently passed away (December last year), and I am dealing with the Probate application.

the total value of the estate is £641,249. this made up of;
main residence he lived in up until his death - £575,000
Cash savings - £40,248
Premium bonds - £20,000
Car - £6,000

I have also just found out, that he gave my uncle (his son) £28,500 (split into 3 amount of £10,000, £17,000 and £1,500) in the past 3 years. I'm assuming this needs to be added to total value of the estate? if so, that make the total £669,749.

Further information
My nan (Granddad's wife) passed away 6 years ago, and everything she owned passed to my Granddad, and none of her tax free allowance was used. So I would like to transfer her allowance to my Granddad's allowance. It is my understanding that her allowance is £500,000. This is made up of:
£325,000 tax free allowance
£175,000 main residence allowance (although she lived in care home for 6 years prior to her death)
My Granddad place his house in trust, before my nan went into the care home (i'm not yet sure what type of trust)

Calculating my Granddad's tax free allowance
the basic tax free allowance is £325,000
plus he qualifies for the main residence allowance £175,000
giving him a total of £500,000
then add my nan's allowance of £500,000
giving my Granddad a total allowance of £1,000,000

Questions
1. have I worked out the allowances correctly, and therefore no inheritance tax is due?
2. does my nan living in a home for 6 years prior to her death mean she doesn't qualify for the main residence allowance?
3. do I need to complete an IHT400 or an IHT435 form?
4. do I need to complete an IHT402 to claim my nan's allowance?
5. Does the trust change things?

thanks again

[dslippy]

It is subject to a question about whether the time limint available on such claims is two years.

[sederunt]

Residence in a care home does not affect the potential for TRNRB, but TRNRB appears not to be relevant here.

There is £650k allowance (NRB+TNRB). Anything above that may be chargeable to IHT - or not chargeable if RNRB is available.

RNRB is available where a house forms part of the estate and is left to direct descendants. It is not stated who inherits and the trust status of the house is not known.

You may be able to reduce the gift totals by the annual gift allowance.

[Strats]

Thanks both. The house has been left to my dad and uncle, who are the only direct descendants.