How much alcohol per guest?
A reasonable planning figure is one drink per guest per hour, for the hours guests are actively drinking rather than the full event length. A 6-hour wedding with a 2-hour meal in the middle is really only 4 hours of active drinking for most guests.
Split across drink types, a typical UK crowd splits roughly 40% wine, 40% beer or similar, and the remaining 20% between spirits and soft drinks — though this shifts a lot by event type and time of day. Daytime events skew toward wine and soft drinks; evening receptions skew toward beer and spirits.
A standard 750ml bottle of wine pours five 150ml glasses, which is the UK's typical large-glass serving size. That's a useful anchor figure: if you know roughly how many glasses of wine your guests will get through, divide by five for bottles.
Because most UK retailers offer sale-or-return on wine and beer, there's little downside to buying slightly more than you calculate — the drinks calculator already rounds figures up rather than down for this reason.
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