In 2016-17, 4.6 per cent of UK deaths resulted in an IHT charge, an increase of 0.4 percentage points since 2015-16. In total UK citizens paid £5.4bn in IHT in 2018/19.

The increase continues a long term trend which began in 2009-10, and is partly due to the freezing of the £325,000 nil-rate band tax-free threshold since April 2009.

About 28,100 estates paid IHT in 2016/17 – up 15 per cent in a year. The proportion of estates liable to IHT has been rising since the nil rate band was frozen in 2009. The figures stood at 2.6 per cent in 2015/16 and jumped to 4.6 per cent in 2016/17.

However, this is still below the peak in 2006/7 when 5.9 per cent of estates paid IHT. This was the year before a rule change meant spouses could pass their IHT nil rate bands on to one another, and before the financial crisis.

Tom Selby, senior analyst at AJ Bell, said: “With the nil-rate band frozen at £325,000 for a decade, it is no surprise that HMRC continues to rake in record sums through IHT.

“The world of IHT is painfully difficult to navigate and while the wealthiest should be able to afford suitable advice to take advantage of the various exemptions and reliefs available, those who can’t risk being caught out.

“As a minimum, the level of the nil-rate band should be looked at again and increased in line with inflation. Ideally a more fundamental government overhaul of the IHT framework should also be undertaken, aimed at simplifying the structures for investors.”

The Office for Tax Simplification recently proposed a series of radical IHT simplifications. These included overhauling gifting rules, and abolishing the tapered rate of IHT.

Sarah Coles, personal finance analyst at Hargreaves Lansdown, said: “A decade of property and share price growth has been a bonanza for the taxman – and he doesn’t let a little thing like death stand in the way of dipping into your pockets for a little bit more.

“The freezing of the IHT threshold for a decade has trapped thousands more people into paying tax when their loved ones die. So as we get older, it’s vital to consider IHT, and take sensible steps to avoid paying more than we have to.”

A study in April identified a lack of awareness around inheritance tax rules (IHT) among Brits, including the gifting limit and the nil-rate-band.