What is the 6-month inheritance tax interest deadline?
The 6-month interest deadline in plain terms
If any inheritance tax on the estate is still unpaid 6 months after the date of death, HMRC starts charging interest on the outstanding amount. This happens automatically — there's no notice sent, and it applies whether or not you knew the estate owed tax yet.
Why the 6-month mark catches executors out
Probate and estate valuation often aren't finished within 6 months of the date of death, so it's easy to reach the interest deadline before you know exactly how much inheritance tax is owed. The interest keeps accruing from that date regardless, on top of whatever tax is eventually due.
What this page is (and isn't)
This is a plain-language explainer, not tax advice — it does not calculate the inheritance tax owed on your estate, and it does not pay or file anything on your behalf. For estate-specific guidance, consult a solicitor or accountant.