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HMRC internal manual

Capital Gains Manual

Expenditure: wasting assets

In general terms, a wasting asset is one whose useful life is limited so that over a period of time it gradually becomes either valueless or worth only scrap value. Where such an asset is disposed of after a period of ownership, the disposal comprises only what is in substance a diminished part of the original asset: the other part has been exhausted by use or passing of time. In recognition of this, the expenditure attributable to the part of the asset which has wasted away by the date of the disposal is excluded from allowable expenditure. Full instructions on wasting assets are at CG76700+.