IHT405 is the HMRC schedule for listing every house, piece of land, building and right over land the deceased owned, such as fishing or mineral rights, with its open market value at the date of death. It goes with the IHT400. The totals feed IHT400 box 51 for the home and boxes 68 to 70 for other land, and if you've got a professional valuation, HMRC wants a copy enclosed.
This guide follows Schedule IHT405 (HMRC 04/26) and the IHT400 Notes, as of October 2026. The April 2026 revision carries the new cap on 100% agricultural and business relief.
What goes on it
Fill it in for all land and buildings, and all rights over land, in the deceased's name. The IHT400 Notes give mineral rights, fishing rights and rights of way as examples of interests that belong here. Jointly owned property is valued on the same principles, but the joint ownership details go on IHT404. If the deceased owned a lot of property, use more than one IHT405.
The columns, A to H
| Column | What to enter |
|---|---|
| A | Item number for each property |
| B | Full address or description. For land without an address, enclose a plan showing the boundaries |
| C | Postcode |
| D | Tenure: freehold, or leasehold with the years left and the annual ground rent |
| E | Lettings: a copy of any lease or tenancy, or the start and end dates and rent; 'vacant' if unoccupied |
| F | Value of agricultural or business relief at 100%, woodlands relief or heritage exemption deducted |
| G | Value of agricultural or business relief at 50% |
| H | Open market value at the date of death |
Box 6 is for the deceased's residence and box 7 for other land, buildings and rights. Copy the column H total from box 6 to IHT400 box 51, and include the box 7 total in IHT400 boxes 68 to 70. Relief claimed goes in IHT400 box 93, with IHT413 for business relief or IHT414 for agricultural relief.
The relief cap from 6 April 2026
The form now spells out the change. 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. That figure includes qualifying gifts made on or after 30 October 2024 within 7 years of the death, and trust property treated as part of the estate. Anything over £2.5 million gets relief at 50%, which is why the form has separate 100% and 50% columns.
An unused £2.5 million allowance from a late spouse or civil partner can be transferred to the estate, as long as the claim is made within 4 years of the survivor's death or within 6 months of the personal representatives starting to act. The form also notes that business relief isn't available for businesses that deal in property or investments.
What open market value means
The IHT400 Notes define it as the price the asset might reasonably fetch if sold on the open market at the time, a realistic selling price, not an insurance or replacement value. For houses and land you may need a professional valuer. If you use one, ask for the open market value at the date of death and send HMRC a copy.
Special factors and damage
Box 8 asks whether anything affects value, such as major damage or development potential. Give details by item number and enclose any survey, structural engineer's report or planning approval. If there's damage, boxes 9 and 10 ask whether the deceased's buildings insurance covers the repairs and whether you'll claim, with copies of correspondence with the insurer or loss adjuster.
Selling within 12 months
Box 11 asks if any property has been sold, or will be, within 12 months of the death. For each one you give:
- Whether it's already sold, on the market now, or to be sold later, with the exchange date if sold (or missives concluded in Scotland).
- The asking price or agreed sale price, without deducting sale costs.
- Whether the buyer is a relative, friend or business colleague of the deceased.
- Any price for fixtures, carpets and curtains included in the sale.
- Whether you want the sale price used as the value at the date of death.
That last question matters, because a sale soon after the death tells HMRC a lot about what the property was worth. And if land is later sold within 4 years for less than the value you returned, the IHT400 Notes say the tax may be reduced, which is claimed on form IHT38.
A checklist before you send it
- List every property and right over land with its own item number.
- Get open market values at the date of death, professional where needed.
- Attach leases, plans, surveys and valuation reports.
- Split any relief between the 100% and 50% columns using the £2.5 million limit.
- Copy the totals to IHT400 boxes 51, 68 to 70 and 93.
- Name a separate valuation contact only if it's not the person in IHT400 box 17.
A plain-English summary of another form is in the overseas estate inheritance tax form guide.
Want AI doing the heavy lifting in your marketing?
I build the systems that handle the boring 80 percent, so you get your week back. Done properly, with the human kept in.
The verdict
IHT405 is where most of an estate's value often sits, so it gets the closest look. Use realistic open market values, enclose the evidence, flag damage or development potential, tell HMRC about any sale within 12 months, and on deaths from 6 April 2026 split relief correctly between the two columns.
A second form worth a look is described in our trust anniversary charge return explainer.
Frequently asked questions
What is IHT405 used for?
It's the IHT400 schedule for houses, land, buildings and interests in land, such as fishing or mineral rights, owned by the deceased.
Which IHT400 box does the IHT405 total go in?
The deceased's residence total goes in IHT400 box 51, and other land and buildings go in boxes 68 to 70.
Do I need a professional valuation for IHT405?
Not always, but if you have one HMRC asks you to enclose a copy with the form.
What changed on IHT405 in April 2026?
For deaths on and after 6 April 2026, 100% agricultural and business relief is limited to £2.5 million of combined qualifying property, with 50% relief above that.
Do I tell HMRC if the house is sold after death?
Yes. Box 11 asks about sales within 12 months of the death, including the price and whether the buyer is connected to the deceased.
What value goes on IHT405?
The open market value at the date of death: the price the property might reasonably fetch if sold on the open market.
