One price, one estate

The executor or administrator of an estate that is not an excepted estate. A small estate is excepted if it is within the nil rate band (£325,000), increased by any unused nil rate band transferred from a late husband, wife or civil partner (up to twice it when none of theirs was used); an estate of up to £3 million can be excepted when what is left after debts and what goes to a spouse or charity is within those limits. Gifts, trusts, foreign assets and some other things change that. An IHT400 is usually needed when tax is due, or when the estate relies on the residence nil rate band or Business or Agricultural Relief. Our free check tells you which applies, and we won't sell the forms for an estate that doesn't need them. The IHT205 short form was abolished for deaths from 1 January 2022.

Inheritance Tax is due by the end of the sixth month after the month of death. Interest is charged after that, currently 7.75% a year. The IHT400 itself must be sent within 12 months of the end of the month of death (HMRC's form asks for it within 12 months of the death). Claims to transfer a late spouse's unused allowances must be made within 2 years.

Yes. We fill in the PDF forms HMRC publishes on gov.uk (Crown copyright, used under the Open Government Licence). You print them, check them, sign page 16 and post them to HMRC with your attachments.

The calculation follows the IHT400, its schedules and the IHT400 Calculation box by box, with the rules in force on the date of death, including the 2026 changes to Business and Agricultural Relief. You stay responsible for the values you enter and for checking the forms before you sign. Where part of an estate needs a specialist, such as trusts, foreign assets, gifts kept in use or Business Relief schedules, we say so plainly and don't sell forms that would leave it out.

The questions and the tax estimate are free. The completed forms, the tax working and your checklist are £149, paid once for one estate. You can change your answers and download again as often as you need.

No. IHT400.com is independent software, not a solicitor or an adviser, and is not affiliated with HMRC. For complex estates, ask a solicitor, chartered tax adviser or accountant.