Inheritance tax confusion

ShepMum

Morning all, newbie here  
I'm an only child who sadly lost her mum years ago, she didn't have a will so everything went straight to my dad.
A friend has told me that when it comes to my dad passing away, I will be entitled to both his £325K allowance AND the same from my mother?!
Is that right?  I can't find any evidence to support it but as dad's estate is over the £325K threshold could have a massive effect on my inheritance!  TIA

Mark_d

It's only the unused portion of the IHT allowance that transfers

https://www.gov.uk/guidance/transferring-unused-basic-threshold-for-inheritance-tax

Keep_pedalling

Mark_d said:

It's only the unused portion of the IHT allowance that transfers

https://www.gov.uk/guidance/transferring-unused-basic-threshold-for-inheritance-tax

The OP said that every thing went to their father so the whole transferable NRB is available to transfer.

The exemption is claimable on the death of the second spouse regardless of the time laps between the deaths. The only complication comes with deaths prior to 1974 where there was no or limited spousal exemption available. 

If his estate is in excess of £650k then his estate may also be sble to claim the residential NRBs which take the total exemptions up to £1M.