IHT412 is the Inheritance Tax schedule for shares that aren't listed for HMRC purposes, such as private company shares and AIM shares, and for any holding that gave the deceased control of a company, listed or not. It's also where you claim Business Relief on those shares. Ordinary listed holdings go on IHT411 instead.
This guide follows Schedule IHT412 (version HMRC 04/26), GOV.UK's Business Relief guidance and the IHT400 Notes, as of October 2026.
IHT411 or IHT412?
IHT412 covers shares that are listed on a market that doesn't meet HMRC's definition of listed, shares in a private limited company, Business Expansion Scheme or Business Start-up Scheme shares, and shares listed on a recognised stock exchange where the deceased had control. Every other holding goes on IHT411, listed stocks and shares. The Alternative Investment Market is the best-known example of a market that isn't listed for HMRC purposes, so AIM shares belong here.
The five boxes and where their totals go
| Box | Holding | Value goes to |
|---|---|---|
| 1 | Traded unlisted shares (for example AIM) without control | IHT400 box 65, or box 66 if paying by instalments |
| 2 | Private company, BES or BSS shares without control | IHT400 box 65, or box 66 if paying by instalments |
| 3 | Private company shares with control | IHT400 box 67 |
| 4 | Traded unlisted shares with control | IHT400 box 67 |
| 5 | Listed shares with control | IHT400 box 67 |
For every holding you also give dividends due at death (totalled to box 64), whether the deceased owned it for 2 years, and the Business Relief claimed. Relief on non-control holdings goes to box 92, and relief on control holdings goes to box 93.
What changed from 6 April 2026
As of October 2026, the form and GOV.UK set out new rules for deaths on and after 6 April 2026:
- Relief at 100% on the combined value of qualifying agricultural and business property is limited to £2.5 million. Above that, the excess qualifies for relief at 50%.
- The £2.5 million includes gifts of qualifying property made on or after 30 October 2024 and within 7 years of the death, plus other property treated as part of the estate, including trust property.
- Any unused allowance of a late spouse or civil partner can be transferred, which GOV.UK says could make the allowance up to £5 million. The claim must be made by the later of 4 years after the death or 6 months after the personal representatives start their role.
- Shares on a market that isn't listed for HMRC purposes, such as AIM, can now only qualify for 50% relief.
That last change is why boxes 1 and 2 now have separate columns for relief at 100% and at 50%, and box 5 only has a 50% column.
The two-year test and binding contracts
Business Relief normally needs the deceased to have owned the shares for at least 2 years before death, which is why every box asks the question. The Notes on the form add two traps. Relief can't be deducted on unlisted shares that were subject to a binding contract for sale at the date of death, unless the sale was to reconstruct or amalgamate the company. And relief isn't due on traded unlisted shares that are quoted on a recognised foreign stock exchange, so check every exchange the company trades on before you claim.
Paying by instalments
From 6 April 2026, the form says you'll be able to pay tax by instalments on any unlisted shares that qualify for Business Relief. Unlisted shares that don't qualify can still qualify for instalments if the tax couldn't be paid in one sum without undue hardship, if at least 20% of the tax the same person is liable for is on instalment assets, or if the shares are worth more than £20,000 and represent at least 10% of the nominal share capital. The IHT400 Notes describe these as 10 annual instalments. If you're using instalments on non-control holdings, put the value in box 66 instead of box 65.
Step by step
- Sort every shareholding into IHT411 (listed, no control) or IHT412 (unlisted, AIM or control).
- Place each IHT412 holding in the right box, 1 to 5, by type and by whether it gave control.
- Value each holding at the date of death and add dividends due but not yet paid.
- Answer the 2-year question and check for any binding contract for sale.
- Split Business Relief between the 100% and 50% columns, applying the £2.5 million allowance across all qualifying property.
- Carry the totals to boxes 64 to 67, 92 and 93 of form IHT400.
The verdict
IHT412 used to be the form where family company shares came off the estate at 100% without much drama. For deaths from 6 April 2026 it needs real care: AIM shares are capped at 50%, the 100% band is shared with farmland and business assets, and gifts since 30 October 2024 eat into it. Value carefully, apportion the allowance across the whole estate, and claim any transferable allowance within the time limit. HMRC's Inheritance Tax helpline is 0300 123 1072, or +44 300 123 1072 if you're calling from outside the UK.
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Business and partnership interests are reported separately, as the business and partnership interests form guide shows.
Frequently asked questions
What is IHT412?
It's the Inheritance Tax schedule for unlisted shares, AIM shares, private company shares and control holdings, including any Business Relief claimed on them.
Do AIM shares go on IHT411 or IHT412?
IHT412. AIM isn't listed for HMRC purposes, so AIM shares are reported on IHT412.
What Business Relief do AIM shares get from April 2026?
For deaths on and after 6 April 2026, shares on a market that isn't listed for HMRC purposes, such as AIM, can only qualify for 50% relief.
What is the £2.5 million Business Relief limit?
For deaths on and after 6 April 2026, 100% relief on the combined value of qualifying agricultural and business property is limited to £2.5 million, with the excess relieved at 50%.
Do shares need to be owned for 2 years for Business Relief?
Yes, relief normally needs the deceased to have owned the shares for at least 2 years before death.
Can tax on unlisted shares be paid by instalments?
From 6 April 2026, tax on unlisted shares that qualify for Business Relief can be paid by instalments, and other unlisted shares can qualify in certain circumstances.
