Transfer of RNRB pre 2017

If Mr X died in 1994 and Mrs x died in 2021 looking at the IHT 436 would it be £100,000 that may be claimed (Notes 1 and 2 on page 3) that could be transferred to Mrs X therefore a total of £275,000). Also with the NRB this was £150,000 in 1994 so would that be added to the £325,000 for Mrs x. No other gifts have been made.

Also if someone died in 2015 would the position be the same regarding RNRB. Thank you Jan

Hi Janet,

The transferable nil rate band and residence nil rate band are based on percentages, not amounts, so if Mr X transferred his estate in entirety to wife, then 100% of his allowances are unused and can be transferred. This will give Mrs X £175 x2 plus £325 x2 = £1m.

Lucy Orrow CTA TEP
Lambert Chapman LLP

Hi Lucy
Thank you so what are the rates actually for on the IHT 436 in notes 2 is this for single people?
Kind regards Jan

Hi Janet,

Transferring unused residence nil rate band for Inheritance Tax - GOV.UK (

FROM HMRC GUIDANCE Work out the percentage of RNRB that was not used when the first of the couple died. You do this by dividing the unused amount of RNRB by the total RNRB that was available when the first of the couple died and multiplying the result by 100. If the person died before 6 April 2017 the unused RNRB and total available RNRB are both deemed to be £100,000 so the unused percentage is 100%.

The £100,000 is just a deemed figure to use not an actual.