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How Much to Drink to Order for an Event

Figuring out how much alcohol per person an event needs isn't a dark art. It's a consumption model, a handful of bottle yields, and a buffer. Get those three right and you order once, cover the room, and don't come home with fourteen unopened cases.

The bar is the part of the quote people panic about most, and it's the part with the cleanest maths. Food is judgement — appetite, menu, time of day. Drinks are arithmetic. There's a well-worn consumption curve, the bottles pour a known number of glasses, and if you build a buffer that comes back as sale-or-return you can be generous without eating the cost. I've run this model on a 40-cover dinner and a 400-guest gala, and it barely changes.

What changes is the crowd. A corporate lunch drinks less than a wedding. A room of people over sixty drinks differently from a 25th-birthday party. So we start with the model, then I'll show you where to lean it up or down, run a full 100-guest example, and finish on the buffer that keeps the whole thing from being a gamble.

The consumption model: two, then one

The number worth memorising: guests drink about two drinks in the first hour and roughly one drink each hour after that. The first hour is front-loaded — people arrive thirsty, they've been travelling, the welcome drink hits, conversation is starting. After that it settles into a steady one-an-hour rhythm through the meal and the speeches.

Total drinks = guests × [ 2 + (hours − 1) × 1 ]

So a four-hour event is 2 + 1 + 1 + 1 = 5 drinks per guest. A three-hour event is 4 per guest. A two-hour drinks reception is 3. That single number — drinks per guest — is the spine of the entire order. Everything else is just splitting it across categories and converting to bottles.

One honest caveat before we go further: this assumes an open bar with a normal adult crowd and alcohol flowing freely. If it's a cash bar, consumption drops by a third or more because people self-ration. If a meaningful share of the room doesn't drink — a dry-leaning crowd, daytime corporate, families with kids — you scale the alcohol down and the soft drinks up. Don't order five drinks a head for a christening.

Splitting the total across categories

Once you know total drinks, you split them by type. The classic banquet split for a mixed adult crowd:

CategoryShare of drinksNotes
Wine50%Split roughly 60/40 white-and-sparkling to red; adjust for menu
Beer30%Higher for casual, summer, or younger crowds
Spirits & cocktails20%Lower if there's no cocktail service; near zero for a simple wine-and-beer bar
Non-alcoholicadd on topBudget 1–2 additional servings per guest, more in heat or daytime

Notice non-alcoholic sits on top of the alcohol total, not inside it. Soft drinks, sparkling water, juice and mocktails are cheap and the thing that runs out first at a summer event. Under-ordering water at a July marquee is the rookie error I see most. Order water like you mean it — a guest will go through three or four still-and-sparkling servings across an afternoon before they touch the wine total.

These splits are a starting frame, not gospel. A whisky-region wedding tilts to spirits. A craft-beer crowd flips beer and wine. A champagne reception is 80% sparkling for the first hour. Read the event, then adjust — but always start from a real split so your adjustment is a decision, not a guess.

Bottle yields: turning drinks into an order

Drinks are what guests consume. Bottles are what you buy. The conversion is fixed and worth knowing cold, because it's where an order goes wrong when someone eyeballs it.

ContainerStandard serveServes per unit
Wine, 750 ml bottle150 ml glass~5 glasses
Sparkling, 750 ml bottle125 ml flute~6 flutes
Spirit, 750 ml bottle45 ml pour~16 pours
Spirit, 1 L bottle45 ml pour~22 pours
Beer1 bottle / can1 serve

The one everybody gets wrong is wine. A 750 ml bottle is five glasses at a proper 150 ml pour — not six, not "about eight." If your event has a heavier-handed pour or larger glasses (many venues pour 175 ml), you're down to four glasses a bottle, and that quietly blows a wine order out by 20%. Decide the pour size first, then divide. For sparkling at a 125 ml flute you get six, which is why a welcome-fizz reception is cheaper per head than it feels.

Spirits are forgiving — sixteen 45 ml pours from a 750 ml bottle, twenty-two from a litre — so a single bottle of gin covers a lot of gin-and-tonics. The trap with spirits isn't the count, it's the mixers: tonic, cola, soda and juice run out long before the spirit does, and they're cheap to over-buy. For a standard-serve reference that keeps everyone honest about what "one drink" actually is, the US NIAAA (standard drink) definition puts it at 5 oz of wine, 12 oz of beer, or 1.5 oz of spirits — which lines up almost exactly with the serve sizes above.

Buy by the case, not the bottle. Wine and beer come in cases of 6, 12 or 24, and suppliers price and deliver by the case. Round your bottle count up to the next full case — it's usually cheaper per unit, and the surplus is your buffer. Never place an order that leaves you three bottles short of a clean case; you'll pay a premium for the top-up on the day.

A worked example: 100 guests, four hours

Here's the whole method end to end. A wedding reception, 100 adult guests, four hours of open bar, mixed crowd, sit-down dinner with a welcome drink.

Step 1 — Total drinks. Four hours = 5 drinks per guest. 100 × 5 = 500 drinks.

Step 2 — Split. Apply 50 / 30 / 20:

Step 3 — Convert to units.

CategoryDrinksYieldUnits neededRounded to case
Wine (150 ml)2505 / bottle50 bottles48 + 6 = 54 (buffer)
Beer1501 / bottle150 bottles7 cases of 24 = 168
Spirits (45 ml)10016 / bottle7 bottles8 bottles + mixers
Soft / water1501 / serve150 servingsround up generously

Fifty bottles of wine sounds like a lot until you see it's five glasses each across a hundred people over four hours — it's exactly right. Split that wine ~60/40: say 32 bottles of white and sparkling, 22 of red, then flex toward whatever the menu and the season pull. A summer garden wedding drinks more white and rosé; a winter dinner with red meat pulls red.

The spirits line looks tiny — eight bottles for a hundred people — and that surprises people every time. It's correct. Twenty per cent of 500 drinks is 100 pours, and eight bottles gives you 128 pours of headroom. What you'll actually run through is the tonic and cola. Order those like the guests are only drinking mixers.

The buffer and sale-or-return

Every number above is an average. Averages have a right-hand tail: the one wedding where the wine goes twice as fast because it's 34°C and the speeches run long. Running dry at an event is the single failure guests remember and talk about. So you build a buffer — but a buffer only makes sense if it doesn't cost you when it's unused.

That's what sale-or-return is for. Most drinks suppliers, and many venues with a corkage arrangement, will take back unopened, undamaged cases at full credit. This changes the whole calculation. Under sale-or-return you can order 15–20% over your model with no downside: what's drunk is billed, what's not comes back. The only rule is keep it sellable — cases stay boxed and out of the sun, chilled stock isn't over-chilled to the point of label damage, and nobody splits a case to grab two bottles.

Get sale-or-return in writing before the event. "We'll sort it out after" is how you end up eating four unopened cases. Confirm the return window (often 48–72 hours), the condition requirements, and who pays for collection. On a large order this clause is worth more than the discount you negotiated on price.

If sale-or-return isn't available — a cash-and-carry run, a small private job — then your buffer has to be tighter and smarter. Buffer the categories that don't spoil and store well: extra beer and spirits keep for the next job; over-ordered fresh garnish and cut fruit do not. Keep the wine buffer to a case or two, over-buy the beer (it always gets drunk eventually), and be honest that a modest surplus of soft drinks and water is cheap insurance against the thing most likely to actually run out.

Where the model bends

The two-then-one curve is the trunk. These are the branches — the adjustments that separate a chef who's done fifty events from one running a calculator for the first time.

Time of day and day of week

A weekday corporate lunch drinks roughly half what a Saturday-night wedding does. Daytime, professional, driving-home crowds self-limit hard. A Friday or Saturday evening celebration with taxis booked is your full five-a-head. Move the per-guest number, not the split.

The crowd

Age, culture and occasion all move the needle. A younger crowd tilts to beer and cocktails; an older one to wine and spirits. A dry or semi-dry crowd means most of your "drinks" become premium soft options — mocktails, good juice, sparkling — and the alcohol total drops sharply. Ask the client the awkward question early: roughly what share of the room drinks? Their honest answer is worth more than any formula.

Whether it's a meal or a standing reception

Seated dinners pace people — a glass is nursed through three courses. Standing receptions with passed canapés drink faster and more continuously; there's no plate to anchor the hand, so the glass gets refilled. A pure two-hour standing reception can hit 3–3.5 drinks a head, above what the flat model predicts. If you're planning the food side of a standing event too, that faster pace is worth reading alongside the canapé and pass-timing decisions.

In ProChefDesk

Set the guest count and duration on an event in the Events tool and the drinks total falls out of the same guarantee number you're already using for the food. Because the bar order scales off confirmed covers, when the guarantee moves from 100 to 120 the beverage line moves with it — you're not re-running the maths by hand the week before.

Costing the bar, not just counting it

Ordering the right quantity is half the job. The other half is knowing what it costs per head, because the bar is often 15–25% of an event's total spend and the easiest line to blow. Once your quantities are set, cost them the same way you cost food: unit price ÷ serves, times servings, plus a margin if you're marking up rather than passing through at cost.

Wine at $12 a bottle poured five glasses deep is $2.40 a glass in raw cost. That gin at $28 a litre is about $1.27 a 45 ml pour before mixer. Line those up against your per-head budget and you can see instantly whether the client's drinks brief fits their number — and where to trade a premium sparkling down to a good prosecco to claw back the margin.

In ProChefDesk

The Buffet planner costs stations on the same per-guest / refill model that works for drinks — a per-head quantity times covers times a refill multiplier — so beverage stations sit next to the food ones in a single per-head figure you can put in front of a client.

The short version

Two drinks the first hour, one an hour after. Split it half wine, a third beer, a fifth spirits, and pile the soft drinks on top. Convert with five glasses a wine bottle and sixteen pours a spirit bottle. Round up to whole cases, add 15–20% buffer under a written sale-or-return, and over-order the water and mixers because those are what actually run dry.

Do that and the bar stops being the scary line on the quote. It becomes the one you're most confident about — priced, portioned, and covered, with the surplus going back to the supplier on Monday morning.

"The wine we counted to the glass. It was the tonic that ran out at nine o'clock." — every caterer, once, before they learned to over-buy the mixers.