IHT418 is the form you send with IHT400 when the person who died had a right to benefit from a trust, and you're acting as executor, or as both executor and trustee. You fill in a separate IHT418 for each trust, and the sections you complete depend on whether you're the executor, the trustee or both.
This guide follows HMRC's IHT418 guidance (updated 16 July 2026) and the IHT400 Notes, as of October 2026.
Which trust interests bring IHT418 in
You must complete IHT418 if the deceased had an interest in possession and the trust is one of these:
| Interest | What it means |
|---|---|
| Set up before 22 March 2006 | A trust the deceased was entitled to benefit from, known then as a qualifying interest in possession |
| Immediate post-death interest | Created by a will or intestacy, with the beneficiary entitled on the settlor's death |
| Disabled person's interest | A trust for a disabled person meeting rules on how income and capital are used |
| Transitional serial interest | Certain successive interests, including a life policy with an unbroken chain of interests |
HMRC's guidance also covers a purchased interest in possession: one bought by the beneficiary in an arm's length deal on or after 9 December 2009 while domiciled in the UK.
Who fills in which section
| Your role | Sections to complete |
|---|---|
| Solely executor or administrator | Sections D and I |
| Solely trustee | Sections E, F, G, H, I and the declaration |
| Both executor and trustee | Sections E, F, G, H, I and the declaration |
Everyone completes Sections A to C: the trust's details, its trustees and your capacity. A trustee includes a copy of the trust deed. If the trust has no Unique Taxpayer Reference, the 10-digit UTR box is left blank.
Why executors and trustees are treated differently
The insight in the IHT400 Notes is that the trustees, not the executors, must give HMRC full details of trust assets and say who pays any tax due. HMRC still needs the net value of the trust to work out the total tax on the estate. Where executors and trustees are the same people, they may give full details on IHT418 and pay the tax when applying for the grant. Where they're different people, or the executor could only give brief details, HMRC asks the trustees to complete a separate account, IHT100b death.
Future rights: reversionary interests
The deceased may have been entitled to trust assets that someone else enjoys for their lifetime, so the estate only receives them after that person dies. That's a reversionary interest, or interest in expectancy. If it applies, you give an estimate of the assets' value at the date of death and the name and age of the person currently benefiting.
The 2025 and 2026 changes
- For deaths on or after 6 April 2025, Inheritance Tax isn't due on foreign assets held in a trust if the beneficiary and the settlor aren't long-term UK residents at the date of the event, with exceptions for indirect interests in UK residential property.
- Transitional rules protect non-UK assets in a qualifying interest in possession settlement that were excluded property immediately before 30 October 2024.
- From 6 April 2026, tax on any shares or securities that qualify for business relief, listed or unlisted, can be paid by instalments.
Valuing and paying
Trust assets are valued the same way as the deceased's own assets: at open market value, as if sold on the date of the event. Round assets and liabilities down to the nearest £1, and show tax to the nearest penny. Section G sorts assets into those where tax can be paid in annual instalments over 10 years and those where it can't.
Tax on unlisted shares that don't qualify for business relief may still be paid by instalments if paying in one go would cause hardship, if at least 20% of the tax is on instalment assets, or if the shares are worth more than £20,000 and make up at least 10% of the company's shares or its ordinary shares.
Life insurance held on trust
If a life policy is held in trust, the Notes ask you to check the terms first. You only report it as part of the estate where the deceased's interest is one of the types that brings the trust's value into their estate. Where that applies, you give HMRC the names and addresses of the trustees, the value of the deceased's interest in the policy, and a copy of the policy. That's the detail HMRC needs to work out whether the policy adds to the tax on the estate.
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Before you start
- Check the deceased's interest is one of the qualifying types above.
- Decide your capacity: executor, trustee or both.
- Get the trust deed, the trustees' details and the trust's UTR.
- List the trust's assets and liabilities, putting each asset in only one section.
- Download the form and complete it in Adobe Reader, not in your browser.
- Keep every document you used; HMRC may ask for them later.
The verdict
IHT418 is a form where the role you hold matters as much as the numbers. If you're the executor only, give what you know and let HMRC go to the trustees. If you're also the trustee, you're giving the full account, so treat it with the same care as the IHT400 itself. And if gifts went into the trust during the deceased's lifetime, they're a separate question for IHT403.
Frequently asked questions
When do I need to fill in IHT418?
When the deceased had a right to benefit from a trust and you're acting as executor, or as both executor and trustee. You fill in a separate form for each trust.
Which sections of IHT418 does an executor complete?
An executor or administrator acting solely in that role fills in Sections D and I, after Sections A to C.
Which trusts count for IHT418?
Interests in possession in trusts set up before 22 March 2006, immediate post-death interests, disabled person's interests and transitional serial interests.
What is a reversionary interest on IHT418?
A future right to trust assets that someone else benefits from during their life. You give an estimated value and the name and age of that person.
Can tax on trust assets be paid by instalments?
Yes, for assets that qualify. Tax on those can be paid in annual instalments over 10 years, usually with interest.
Do I send the trust deed with IHT418?
If you're completing the form as a trustee, include a copy of the trust deed.
