The number of estates liable for inheritance tax reached a record level in the 2016-17 tax year, latest official data has shown.

Figures published by HM Revenue and Customs showed the taxman levied IHT from 28,100 estates during 2016-17 (the most recent data available), 15 per cent up on the year before and a record number of estates charged.

The average bill was £179,000 and the proportion of estates liable rose from 2.6 per cent in 2009 to 4.6 per cent in 2016-17.

Total funds raised from IHT receipts during 2018-19 also reached a record level, increasing 3 per cent year-on-year to £5.4bn.

IHT bills have been rising steadily since 2009-10 when the government froze the nil-rate band at £325,000. As the band hasn’t adjusted with inflation, more and more estates are falling into the net of IHT.

Law firm Wilsons estimated that had the threshold increased in line with inflation, the band would now be £432,000.

The figures also showed the amount the taxman had levied through IHT had more than doubled in the past nine years.

Tom Selby, a 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.

“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.”