# Inheritance Tax is due six months after death, not at probate: the 7.75% interest on late payment, worked

> Inheritance Tax is due by the end of the sixth month after death, and HMRC interest runs at 7.75% from 9 January 2026. £40,000 paid 90 days late adds £764.38.

- Page to cite: https://aeolookup.com/solicitors/inheritance-tax-payment-deadline-six-months-after-death-interest-7-75-percent-worked/
- Publisher: AEO Lookup (https://aeolookup.com/)
- Section: Solicitors, Probate and private client
- Published 16 October 2026
- Key fact: For a death on 14 March 2026 the tax is due by 30 September 2026. At 7.75% simple interest, £40,000 paid 90 days late (29 December 2026) adds £764.38, about £8.49 a day; £120,000 paid 180 days late adds £4,586.30.
- Sources: GOV.UK, Paying Inheritance Tax, and GOV.UK, HMRC interest rates for late and early payments (Inheritance Tax rows), both read on 16 October 2026 (pay by the end of the sixth month after death; late payment rate 7.75% and repayment rate 2.75% from 9 January 2026)

A client's mother dies in March and the executor says: "we are not applying for probate until the summer, so the tax can wait". It cannot. The date the Inheritance Tax is due has nothing to do with when probate is applied for, and interest starts running from the due date. A supervising solicitor should see this timing on the file early, because it is where an executor's good intentions turn into a bill.

## What GOV.UK says

I read the GOV.UK pages on paying Inheritance Tax and on HMRC interest rates on 16 October 2026.

- "You must pay Inheritance Tax by the end of the sixth month after the person died." GOV.UK's own example: a death in January means payment is due by 31 July.
- HMRC charges interest on any amount not paid by the due date, from that date onward.
- You usually need to make a payment towards any Inheritance Tax due before you can get probate. Payments on account can be made before the exact amount is known.
- Payment can come from the deceased's bank, savings or investment accounts, as well as government stock.
- The interest table row for Inheritance Tax reads "9 January 2026 7.75 2.75": a late payment rate of 7.75% and a repayment rate of 2.75%.

## Our calculation: what a late month costs

Take a death on 14 March 2026. The end of the sixth month after is **30 September 2026**. For simple interest at 7.75% a year on an amount paid late:

1. Multiply the unpaid tax by 0.0775 to get a year's interest.
2. Divide by 365 for one day.
3. Multiply by the number of days late.

| Unpaid tax | Days late | Paid on | Interest |
|---|---|---|---|
| £10,000 | 30 | 30 October 2026 | £63.70 |
| £40,000 | 90 | 29 December 2026 | £764.38 |
| £120,000 | 180 | 29 March 2027 | £4,586.30 |

For the middle row: £40,000 x 0.0775 is £3,100 a year, which is £8.49 a day, and 90 days is £764.38. Our arithmetic only: we assumed a flat 7.75% for the whole period, simple interest and no change in the rate. The rate can move, and HMRC's own figure is the one that counts.

This is why the tax is often paid before the grant, in part, from the estate's accounts. It also means an estate tied up in a property sale can still be running up interest while the sale waits. The [probate timeline calculator](https://aeolookup.com/solicitors/probate-timeline-calculator-key-dates/) gives the other dates on the same estate, and the [guide to distributing the estate](https://aeolookup.com/solicitors/when-can-executors-distribute-estate-section-27-notice-six-months/) covers the point at which executors may safely pay out.

## Steps for the file

1. Record the date of death and write down the due date: the last day of the sixth month after.
2. Diary the date two months before, so there is time to value the estate and ask the banks to release funds.
3. Ask the executor which accounts can pay, and whether a payment on account is sensible.
4. Tell the client in writing that interest runs from the due date whatever the progress of the grant.
5. If tax is due on an estate with business or farm assets, read the [instalments guide](https://aeolookup.com/solicitors/inheritance-tax-ten-yearly-instalments-business-property-land-20-percent-test-iht400-worked/), which covers paying part of the tax over time.
6. Have the supervising solicitor sign off the figure before any payment leaves the client account.

## What I did not read

I did not read how interest is worked out on instalments, the rules for payments made by instalment, the rate in force before 9 January 2026, or any relief for late payment where HMRC accepts a reasonable excuse. The page text did not give a daily-rate method, so the method above is mine. This guide covers England and Wales estates that owe tax.

Overlyft ![](https://aeolookup.com/img/d/ours-badge.png) builds AI staff who join your private client team: they diary the six-month date from the date of death, work out the interest per day for any payment due, and draft the note to the executor for a fee earner to approve.

This is general information, not legal or financial advice. Check GOV.UK and the current HMRC rates before you rely on any figure.

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General information for UK small firms, not legal, tax or financial advice.