Valuing shares for probate means recording what each shareholding was worth on the date the person died, not what it is worth today, and reporting those figures to HMRC in the right way.
Listed shares use HMRC's quarter-up rule; unit trusts, AIM shares, private company shares and platform portfolios each use a different method. This guide sets out each one, the HMRC form it belongs on, and the 2026 changes older guides miss. Figures are as at August 2026 and subject to change.
How do you value shares for probate?
You value shares for probate at their market value on the date of death. Gather every holding, get a date-of-death price for each, and total them for the inheritance tax account. Listed shares use the quarter-up rule; other holdings use the method for their type. The valuation feeds HMRC forms IHT411 or IHT412.
- List every holding. Work through share certificates, dividend vouchers, broker and platform statements, and ISA paperwork, noting the company and number of shares.
- Fix the valuation date. Use the date of death. If the person died on a day the market was closed, you may use the closing price on the last trading day before or the first trading day after, choosing the lower for each holding (gov.uk, as at August 2026).
- Get a price for each holding. Apply the quarter-up rule to listed shares, or ask the broker, platform or fund manager for a written date-of-death valuation.
- Add dividends due but unpaid. Where a share was quoted "ex-dividend" (XD) at the date of death, add the dividend owed to that holding's value.
- Total and report. Enter listed holdings on IHT411 and unlisted or AIM holdings on IHT412, then carry the totals into the IHT400 account.
What is the quarter-up method?
The quarter-up method is HMRC's rule for valuing listed shares. Take the lower of the two closing prices quoted on the date of death, then add a quarter of the difference between the higher and lower price. The result, multiplied by the number of shares, is the probate value of that holding.
Suppose a holding of 2,000 shares was quoted on the date of death at a low of 1,091p and a high of 1,101p.
- Difference between the two prices: 1,101p minus 1,091p equals 10p.
- A quarter of the difference: 10p multiplied by 0.25 equals 2.5p.
- Add it to the lower price: 1,091p plus 2.5p equals 1,093.5p per share.
- Multiply by the holding: 1,093.5p times 2,000 equals £21,870.
Your stockbroker can supply the figures, often as a full probate valuation for a fee. Keep the calculation on file in case HMRC queries it.
How do you value different shares and investments?
The method depends on the holding. Listed shares use quarter-up; unit trusts and OEICs use the bid price; platform portfolios use a date-of-death statement; AIM and private company shares are treated as unlisted. Each type has a matching HMRC schedule.
| Holding type | How to value at the date of death | HMRC form |
|---|---|---|
| Shares listed on a recognised exchange (LSE main market) | Quarter-up rule, plus any XD dividend due | IHT411 |
| Unit trusts and OEICs | Bid price on the date of death, from the fund manager | IHT411 |
| Platform or wrap portfolio (Hargreaves Lansdown, AJ Bell, Fidelity) | Request a written date-of-death valuation statement | IHT411 |
| AIM-listed shares | Market maker or platform price at the date of death; AIM counts as unlisted for IHT | IHT412 |
| Private or unquoted company shares | Formal valuation, often via an accountant; HMRC's Shares and Assets Valuation may review it | IHT412 |
| Stocks and shares ISA | Value the underlying holdings as above; the ISA wrapper does not change the figure | IHT411 / IHT412 |
| Premium Bonds and NS&I products | Face value at the date of death, from NS&I; include any unclaimed prizes | IHT406 |
Form allocations per gov.uk IHT412 and gov.uk share valuation guidance, as at August 2026, subject to change.
What do executors most often get wrong?
The common errors are using today's share price instead of the date-of-death figure, treating a stocks and shares ISA as tax free on death, and assuming AIM shares are still fully exempt from inheritance tax. Each can lead to an incorrect account or an unexpected tax bill.
Using the current price. HMRC wants the date-of-death value worked out with the quarter-up rule, not the live market price or the mid price shown on a trading app. A wrong-method figure is a frequent reason accounts are queried.
Assuming an ISA escapes inheritance tax. The tax-free growth inside a stocks and shares ISA ends at death. The holdings still form part of the estate and count towards inheritance tax.
Quoting old AIM relief. Many guides still say AIM shares held for two years are 100% free of inheritance tax. From 6 April 2026, Business Relief on qualifying AIM shares is 50%, not 100% (gov.uk, as at August 2026, subject to change). The wider reform also caps 100% relief at the first £2,500,000 of qualifying business assets per person, transferable to £5,000,000 for a couple, with 50% above that.
When should you use a professional valuation?
A single listed holding can often be valued in-house with the quarter-up rule. A professional valuation is worth considering where there are several portfolios, private company or AIM shares, a controlling interest, or an estate near the inheritance tax threshold, where errors can be costly to correct.
Unquoted and controlling holdings usually need an accountant or specialist valuer, and HMRC's Shares and Assets Valuation team may review the figure. Where the estate could face inheritance tax, many executors take advice before submitting the account. See our guide to what probate is and how it works, our inheritance tax guide, and our pricing page.
Frequently asked questions
What date do you value shares at for probate?
You value shares at their market value on the date the person died. If the person died on a day the stock exchange was closed, you may use the closing price on the last trading day before death or the first trading day after, and you can pick the lower figure for each holding separately.
Do you need a professional valuation of shares for probate?
Not always. A single listed shareholding can often be valued using HMRC's quarter-up rule or a broker's probate valuation. A professional valuation is more useful where there are private company shares, AIM holdings, a controlling interest, or several portfolios, or where the estate may face inheritance tax and an error would be costly.
Are ISAs subject to inheritance tax on death?
Yes. A stocks and shares ISA is generally part of the estate and counts towards inheritance tax, even though its income and gains were tax free during the person's lifetime. A surviving spouse or civil partner may inherit an additional ISA allowance, but that does not remove the value from the estate.
Are AIM shares still exempt from inheritance tax?
Not fully. From 6 April 2026, Business Relief on qualifying AIM shares is 50%, so half the value can still be liable to inheritance tax, where the shares meet the conditions. Older guides that describe AIM shares as 100% exempt reflect the rules before that date. This is general information and the reliefs are subject to change.
Do you pay capital gains tax on shares during probate?
The estate may pay capital gains tax if shares are sold during administration for more than their date-of-death value, above the estate's annual exempt amount of £3,000 for 2026 to 2027 (gov.uk, as at August 2026, subject to change). The rate on shares for personal representatives is 24% (gov.uk, as at August 2026, subject to change). The date-of-death probate value becomes the base cost for that calculation.