IHTM09242 | Ascertained values: when is a value `ascertained`?
From HM Revenue & Customs · Inheritance Tax Manual
A value is ‘ascertained’ when
the taxpayer and HMRC expressly agree a figure – so if the Valuation Office Agency (VOA) () provides an agreed report (), the value of the property is ‘ascertained’
we accept a value implicitly by accepting the tax on the value offered by the taxpayer: for example where the VOA provides an ‘as returned’ () report, or we collect the tax on a valuable chattel without expressly agreeing the value, or
the taxpayer claims loss on sale of land relief (), when the substituted value becomes the ascertained value.