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HMRC internal manual

Capital Gains Manual

Wasting assets: railway locomotives

Railway locomotives, tramway engines and the like are regarded as machinery for the purposes of TCGA92 and are, therefore, treated as wasting assets.  This applies whatever the size or gauge of the locomotive or engine and whatever method of propulsion (steam, diesel or electricity) it uses.  A disposal of such a locomotive will only give rise to a chargeable gain where capital allowances were, or could have been, claimed.  See CG15400+ for cases where capital allowances are involved.