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HMRC internal manual

Inheritance Tax Manual

Liabilities: investigating liabilities: contingent liabilities

If, at the date of death, a debt is contingent on certain events happening, the extent to which the debt may be allowed as a deduction will depend on the facts available at that time. You will need to take account of the likelihood of those events happening and the likely length of time before the debt will be paid.

In cases of doubt you should consult Technical who can refer to the Actuarial Team if required.

There are separate instructions for dealing with future debts (IHTM28110) where the liability is known but is not payable until some later date and contingent Inheritance Tax liabilities (IHTM28171).