Eight of the top 10 fastest growing areas for inheritance tax earn less than the average annual salary, according to research by London law firm Boodle Hatfield.

The research revealed that IHT is increasingly having to be paid by middle income families, partly because the rate at which IHT starts to be paid has not been changed for over a decade.

For example, Cardiff North saw the number of estates liable for IHT grow 47 percent from 30 in 2014-15 to 44 in 2019-20, despite the av...