Form

Claim unused allowance for agricultural property or business property relief (IHT437)

Use form IHT437 to claim and transfer any unused relief allowance for agricultural or business property to the deceased’s estate.

• From: HM Revenue & Customs
• Published: 8 April 2026

Documents

Claim to transfer unused relief allowance for agricultural property or business property (IHT437)

Ref: IHT437

PDF, 1.33 MB, 3 pages

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Details

Use the IHT437 with form IHT400 to transfer any of the unused 100% relief allowance from the previously deceased spouse or civil partner, to the deceased’s estate.

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Where to send the form

After you’ve filled in the form, send it to the postal address given at Inheritance Tax: general enquiries.

Related guidance

Find out:

• how to work out Agricultural Relief for Inheritance Tax
• what qualifies for Business Relief for Inheritance Tax

Published 8 April 2026