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HMRC internal manual

VAT Food

Items benefiting from the relief: what is food?: food packaging: self-heating packaging

This concerns a specific product in packaging that, when opened or upon shaking, contains chemicals that react and heat the contents of the package (in that case, a tin). We view this packaging as a necessary part of the supply of the food, and it will follow the liability of the contents. It is not a supply of hot food as, at the time of supply, the food is not hot. It was also of note that the packaging was not reusable.