Help/Advice .... Residence Nil Rate Band to Increase Inheritance Tax Allowance

[JustFrank]

My precious sister sadly passed away, just before Xmas.
She was single and has left a minor child, so any money left from her Estate, will be put in trust for him. I am the Executor of her Will. There are some personal/charitable bequests and her property, their family home, which she owned outright, is part of the Estate and is valued at £300K.
I know that the Personal Inheritance Tax allowance is £325K, but I've read, that if a home has been left to a direct family member, ie a child, you can apply for an additional £175K of Inheritance Tax allowance, known as Residence Nil Rate Band. That will increase the IHT Allowance to £500K, so no inheritance tax will be due.
However, I've contacted HMRC and they've sent me IHT400 plus other forms and I'm confused as one person at HMRC said if no inheritance tax due, then I don't need to fill in the IHT400 form....
It's all very stressful, trying to get this done, so I can apply for Probate, to execute the Will, while grieving and trying to do the best, for my young nephews future.
Any help or guidance would be much appreciated. If you can't help, maybe you could point me in the right direction.... Thank you so much

[Sam101]

With the details you have supplied the IHT400 form would not be needed if the death was after 1st January 2020, but before that the form was needed which is why they have sent it to you

If you have already submitted the death certificate and application, then try looking at the online form IHT400 as I understand that it is easier, but there should not be any IHT to pay..