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HMRC internal manual

Inheritance Tax Manual

Calculating the loss: interest on government securities

Securities marked ‘1k’

Where Government securities are marked ‘1k’ (IHTM18098) the date of death value of the holding for the purposes of this relief is the same as the valuation for IHT purposes generally, that is, the bargain price plus the gross accrued interest. 

Interest accrued at the date of sale must also be included in the gross sale proceeds.

Securities marked ‘1k-xd’

Where a security is marked ‘1k-xd’ (IHTM18098) the market price is the amount payable, less an amount equal to the gross interest accruing from the date the bargain was done to the interest payment date.  This is the date of death value for the purposes of this relief.

For securities marked ‘1k-xd’ at the date of sale, the gross proceeds of sale should be calculated in the same way.