IHT400

[source: gov-uk/iht-400-2026-09-26.html]

IHT400 is the full Inheritance Tax return for the UK. The executor or administrator files it with HMRC when the estate is not an excepted estate. It records the assets, debts, gifts, and reliefs that determine how much, if any, Inheritance Tax is due. [source: gov-uk/iht-400-2026-09-26.html]

A range of supplementary forms accompanies IHT400 depending on what the estate contains: jointly-owned property, foreign domicile, lifetime gifts, trusts, business interests, and pension scheme entitlements each have their own supplement. [source: gov-uk/iht-400-2026-09-26.html]

In practice IHT400 is filed before the Grant of Probate or Letters of Administration application can complete. Once HMRC has the form and any tax due has been paid or arranged, it sends a unique code that the executor needs to apply for probate in England and Wales; in Northern Ireland it stamps and returns the IHT421, and in Scotland the C1. A clearance certificate (form IHT30) is a separate, later step once all the tax is paid; it is not needed to get the grant. Tax is due 6 months after the end of the month in which the person died, with interest accruing thereafter. Many UK banks operate a direct payment scheme that releases funds from the deceased's account directly to HMRC before the grant is issued, addressing the catch-22 of needing tax paid before assets can be unlocked. [source: gov-uk/iht-400-2026-09-26.html] [source: gov-uk/paying-inheritance-tax-deceaseds-bank-account-2026-11-01.html] [source: gov-uk/iht30-clearance-certificate-2026-11-01.html]

For estates that owe no tax but don't qualify as excepted (because of a gift, a small foreign asset, or a trust), IHT400 is still required. → Inheritance Tax

Last verified: 28 September 2026 against the gov.uk IHT400 publication. [source: gov-uk/iht-400-2026-09-26.html]

AfterLoss

Our inheritance tax guide explains when IHT400 is needed, the supplementary schedules, and the direct payment scheme banks operate to settle tax before the grant. Information and Documents keeps the asset valuations, gift records, and IHT400 supplementary schedules together, so the figures HMRC sees match the paper trail behind them.