If you have any clients that are VAT Registered and offer any form of seating or a place to eat in their premise, then they will need to ask each individual customer if they will be eating in or out of the establishment.

If they opt to eat in, then VAT will need to be applied regardless of whether the food served is hot or cold and also even if it is normally zero rated; for example a cold sandwich.

To read the full HMRC article please see the link below: