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HMRC internal manual

VAT Water and Sewerage Services

Supplies of water: supplies to offices of businesses performing ‘relevant industrial activities’

Water (for drinking, washing, flushing toilets, etc.) supplied to an office of a manufacturing company whose predominant activity is covered by SIC Codes 1-5 is standard-rated, as it is used in connection with that industrial activity, even though no actual manufacturing is carried on in that office.