This part of GOV.UK is being rebuilt – find out what beta means

HMRC internal manual

Capital Gains Manual

Computation: interaction with other taxes: IT: exclusion of expenditure

TCGA92/S39 (2) makes clear that no expenditure of a revenue nature is allowable. It expressly prohibits the allowance of any sum which would have been deducted in computing the profits of a trade, if the asset in question had been a fixed asset in use for the purposes of the trade. See Emmerson v Computer Time International Ltd (in liquidation), 50TC628.