Free pouring gin, rum, vodka or whisky in a UK pub is illegal unless the drink is a cocktail of three or more liquids. Those four spirits must go out in 25ml or 35ml measures, or multiples, through Government-stamped optics or stamped thimbles. A speed pourer in the bottle neck does not count as a measure, whatever the markings on it say. And beyond the law there is a stock control question: every millilitre a pour runs over spec is stock your count will flag and your till will never explain.
I get asked about this more than you would think, usually by someone who has watched a cocktail bar free pour on holiday and wondered why their own bar is still clicking optics. So here is the actual law, what kit satisfies it, and what each choice does to your variance line.
The law, in one table
The rules come from the Weights and Measures (Intoxicating Liquor) Order 1988 and they only name four spirits: gin, rum, vodka and whisky. Sold by the glass for drinking on the premises, those four must be served in one of the permitted quantities.
| Drink | Legal measures by the glass |
|---|---|
| Gin, rum, vodka, whisky | 25ml or 35ml, or multiples of one of them. One size per premises, not both |
| Still wine | 125ml, 175ml, or multiples |
| Port, sherry, fortified wine | 50ml, 70ml, or multiples |
| Draught beer and cider | Third, half, two thirds of a pint, or multiples of half a pint |
You pick 25ml or 35ml for the whole premises and you display a notice saying which. Every bar in the building uses the same one. You cannot do 25ml singles downstairs and 35ml singles in the function room.
Two things people get wrong. First, the four named spirits are the whole list. Tequila, brandy, sambuca, liqueurs and everything else in the speed rail have no prescribed measure, though if your price list states a quantity you must actually serve that quantity, and you should advertise what measure you use. Second, there is a cocktail exemption: when gin, rum, vodka or whisky goes into a mixture of three or more liquids, the measure rules do not apply to it. A vodka and coke is two liquids, so it must be measured. A vodka, lime and soda is three, so legally it need not be. That is the line, odd as it looks across the bar.
What counts as a legal measure
The quantity has to come from measuring kit the law recognises. In practice that means Government-stamped optics on the wall, or stamped thimble measures in the hand. Both are built to guarantee the quantity.
The speed pourer is the trap. Trading standards guidance is blunt about it: bottle-top pourers must not be used to determine measures of gin, rum, vodka and whisky even when they carry a quantity marking, because they are not legally accurate. They are cocktail kit. You can leave one in the bottle for convenience, but the serve still has to go through a stamped thimble before it reaches the glass.
So the free pour count you have seen behind trend-led bars, four counts and tip the bottle, only survives in this country inside that cocktail exemption. For neat serves and single-mixer serves of the big four, it is a breach of weights and measures law, and it is trading standards who come asking, not the licensing officer.
Optics or thimbles: the stocktaking difference
Both are legal. They behave differently in the stock room.
Optics deliver the same quantity every time while the valve is clean and the seal is good. A tired optic starts short-delivering or dribbling, and because nobody watches an optic pour, drift goes unnoticed until the count. They also lock a bottle to a bracket, which slows a busy back bar and looks wrong under a premium gin shelf.
Thimbles are faster, they suit the gin-and-garnish serve, and a stamped thimble cannot drift. What changes is the human bit: a thimble filled to a wobble over the rim, or a splash more added in front of a regular, is an over-pour the kit was supposed to prevent. Nothing sinister in it. A generous pour feels like hospitality in the moment. It is still stock leaving the building unrecorded.
What over-pouring does to your numbers
A 70cl bottle holds 28 measures at 25ml. Let the average pour creep to just 28ml, a difference no eye can see, and the same bottle serves 25. Three measures gone. At £3.60 a single that is £10.80 of till revenue per bottle that turns up on your stocktake as missing spirit. Get through ten bottles a week across the back bar and the year runs past £5,000. Those are my own illustrative figures, not a survey, but do the sum with your own prices and pace and the shape holds.
The nasty part is what the variance looks like. Over-pouring does not show up labelled as over-pouring. It shows up as spirits lines going short with no matching till story, which is exactly what theft looks like, and I have watched that suspicion sour a good team when the real cause was a wobbly thimble habit and an optic past its best. Measure the pours before you ever question the people. My guide on what pours actually cost goes deeper on that.
Catching it is a counting problem, and it is why I weigh spirits instead of eyeballing tenths. Weighing a part bottle tells you what actually left it to the millilitre, and week on week that is the difference between guessing and knowing. The method is in the spirits weighing guide, and line checks will tell you which week the creep started. If the GP report is where you first noticed something off, read this before you panic.
Where I have landed after nineteen years
Thimbles for the back bar, optics only where a house pour gets hammered, and the spirits weighed on the count. Free pour has no place in a wet-led community pub: the law only allows it in cocktails, and cocktails are precisely where a batched, costed recipe beats a bartender's count anyway. If you batch for a big night, cost the batch per serve and give it its own till button so the sale matches the stock, or the batch turns into a till-button variance you will chase for a fortnight.
One more honest note. Stamped kit satisfies trading standards, but it does not satisfy your stocktake by itself. An optic can be legal and worn. A thimble can be legal and over-filled. The measure is the promise; the count is the check. Run both.
Sources
- gov.uk, Weights and measures: the law, specified quantities — legal measures for spirits, wine, fortified wine and draught beer.
- The Weights and Measures (Intoxicating Liquor) Order 1988 — the four named spirits, the single-size rule, the notice requirement, and the exemption for mixtures of three or more liquids.
- Business Companion (Chartered Trading Standards Institute), Selling alcohol in licensed premises — stamped measuring instruments and thimbles; bottle-top pourers not legally accurate for the four named spirits.
- British Institute of Innkeeping, Alcohol measures — cocktail defined as three or more liquids not counting water; other spirits outside the prescribed list; advertising the measure used.
- Bottle arithmetic (28 versus 25 measures from a 70cl bottle, £10.80 per bottle, £5,000 a year) is the author’s own illustrative working at £3.60 a single, not a published statistic.