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HMRC internal manual

VAT Betting and Gaming Guidance

Machine games: what is a machine game?: definition of a dutiable machine game

A dutiable machine game (whether of skill or chance or both) is one played on a machine for a cash prize, where at least one of the cash prizes is bigger than the smallest amount that’s paid to play the game. Machine Game Duty is payable on such a game but it would be exempt from VAT. The value of the supply is the net takings from the machine.