VATVAL02100 - Monetary consideration: the law
The UK provision that sets out the general rule for the valuation of a monetary consideration is in the VAT Act 1994, section 19(2) -.
“If the supply is for a consideration in money its value shall be taken to be such amount as, with the addition of the VAT chargeable, is equal to the consideration”.
This is valuation on a VAT-inclusive basis - the value for VAT is that part of the payment which, when added to the VAT itself, gives a total equalling the payment.