IHT tax liabilities created in 2022-23 were £6.7bn, up £0.71bn or 12% compared to the previous year.
The total number of UK deaths that resulted in an IHT charge rose 3,700 or 13% to 31,500.
The figures were revealed in the latest Annual Inheritance Tax liability statistics from HMRC for the tax year 2022 to 2023.
The data showed that 4.62% of UK deaths resulted in an IHT charge, up 0.23 percentage points over the year.
Ian Dyall, head of estate planning at wealth management firm Evelyn Partners, said: ‘The data confirms what we already know: that more families are incurring inheritance tax liabilities, and more assets in each estate are becoming subject to tax – even before the IHT measures announced at the last Budget take effect.
“As asset prices, especially equities and property, continue to rise, the frozen nil-rate bands offer less and less protection against IHT and families that take no steps to mitigate their liabilities will either get drawn into the scope of IHT or have the tax levied on a greater proportion of their assets.”
He said the OBR forecasts total IHT liabilities for 2024/25 will rise 11.6% to £8.4bn, while receipts data shows HMRC has so far taken £8.2bn for that period. The OBR also forecasts that in the current 2025/26 tax year IHT will raise £9.1bn.
He pointed out that the bulk of liabilities tend to be fairly concentrated among a small number of large estates. About 6,400 families with net wealth greater than £1.5m paid £4.3bn in IHT – or 64% of the total.
Mr Dyall said: “Families with that level of wealth tend not to garner much sympathy but the Treasury cannot sustainably prop up the public finances by taxing the wealthiest 1 or 2 per cent forever without consequence.”
John O’Connell, chief executive of the TaxPayers' Alliance, said: "Frozen inheritance tax thresholds and rising house prices are dragging more and more grieving families into paying the hated death duty.
“Yet in the ultimate sign that the government views wealth and affluence with contempt and envy, the only changes they have made have been to hammer family businesses and farms. Whoever makes up the next government should scrap inheritance tax in its entirety.”