HM Revenue and Customs (HMRC) has collected more than £6bn ($8bn, €7bn) in inheritance tax (IHT) in the past 12 months.
This is the first time IHT bills have gone over the £6bn mark, research by accountancy group UHY Hacker Young found.
The sum increased from £5.04bn to $6.01bn (up 19%) in the last year.
The firm said that the impact of covid and record-high property prices meant that a larger than usual number of estates became liable for IHT.
Additionally, the government’s freezing of the tax-free allowance until at least 2026, contributed to widening the pool of estates owing IHT.
Mark Giddens, partner at UHY Hacker Young, said: “Inheritance tax is becoming ever-more lucrative for HMRC, as the latest figures show.
“A tax that was original supposed to affect only the super-rich is increasingly hitting middle England. As a result, families increasingly understand the importance of tax planning to ensure they can pass the fruits of their labour to their children.
“The pandemic has led to record peacetime borrowing, and the Treasury will be looking to balance the books any way it can.”