Readers’ forum: Do I need to inform HMRC of ex clients’ death?

Last year a husband and wife client moved back abroad in tax year 2022-23. They are both Norwegian domiciled and they have moved to a town in Sweden close to the border (to avoid the Norwegian wealth tax – policy makers please note). They are in their late sixties and are semi-retired. They are still partly active in the oil industry.

They were resident in the UK for 20 years and hence deemed domiciled with a five-year inheritance tax run off period. While in this country they ran consultancy businesses which have now ceased. They have no residual UK assets.

They ceased being clients after I submitted the 2022-23 tax returns. I am still in contact with them on a personal basis.

My question is: if either or both of them die in the five-year inheritance tax period do I have any responsibility to inform...