Scrapping inheritance tax would cost almost £15bn a year in lost revenue by 2032, the Institute for Fiscal Studies has concluded.
The move has been floated by Number 10, but the IFS questioned where the value would be.
The think tank said the latest figures from HMRC showed fewer than 4% of estates paid inheritance tax in 2020-21, but the rapid growth in wealth among older individuals meant this number was set to rise to more than 7% over the next decade.
The IFS report Reforming Inheritance Tax found that in 2024 the wealthiest fifth of donors will bequeath an average of £380,000 per child, and pay inheritance tax of about 10% of this amount.
By contrast, the least wealthy fifth of parents will leave less than £2,000 per child.
