Four ways to pay for the same drinks
The quantity question and the billing question get tangled together, and they are separate. How much people drink is an assumption about your guests. How you pay for it is a contract structure, and there are four common ones, each of which puts the risk somewhere different.
| Route | Who carries the risk | Where it goes wrong |
|---|---|---|
| Billed on consumption | You do, entirely | The bill is unknown until the night ends |
| Per-person package | The venue does | You pay for everyone, including the quarter of the room not drinking |
| Cash bar | Your guests do | Queues, and guests who did not bring a card |
| You supply it | You do, up front | Corkage, staff, leftovers, and rules you did not check |
A package is insurance. Like all insurance it is priced above the expected loss, which means it is worth buying when the variance would hurt and worth skipping when it would not. That is the whole decision, and the crossover figure in the results tells you which side of it you are on.
The crossover point, and why the venue does not mention it
A package priced per guest and a consumption bar priced per drink are equal at one specific number of servings: the package total divided by the price per drink. Above that number the package saves money, below it the consumption bar does. With the defaults on this page the package costs 120 times 55 dollars, and at 9 dollars a serving that is equal at roughly 733 servings across 95 drinking guests. Your planning figure of 570 servings sits well below it, so consumption billing wins on those assumptions.
Notice how sensitive that is to the count of people who are not drinking. The package bills all 120 guests; the consumption bar bills only what the 95 drink. Every non-drinking guest pushes the crossover further away, which is why the package is a worse deal for a room with a lot of children, drivers or people who simply do not. The results show that charge as its own line.
Kegs, cases and the lump you cannot avoid
If you supply the beer, the container size decides the waste. A half barrel holds about 165 twelve-ounce servings, a quarter barrel about 82, and a sixth barrel about 55. Those are the only quantities you can buy, so a plan for 314 servings buys two half barrels and 330 servings arrive. Cases give finer resolution — 24 at a time — and usually cost more per serving, plus they need ice, space and somewhere for the empties.
Wine and spirits divide more gracefully. A 750 mL bottle gives five standard five-ounce pours, or sixteen one-and-a-half-ounce measures. The calculator rounds each up to the whole bottle, which is what actually happens at the counter. Corkage, if the venue charges it, is per bottle opened, so the fine resolution of cases works against you there: a hundred bottles of beer at a per-bottle corkage costs far more than two kegs.
Bartenders are a queue problem, not a cost problem
The number of bartenders is usually discussed as a line in the budget, which understates it. A bar that cannot keep up produces a queue, the queue empties the room during the part of the evening you paid a photographer to cover, and nobody remembers the sixty dollars you saved. Guests per bartender is an input here rather than a fixed figure because it depends on what is being poured — cocktails made to order take far longer than beer and wine — and on whether drinks are also being passed on trays.
Two structural fixes cost nothing. Serve a limited selection and pour it faster. And open a second short-lived station for the first thirty minutes, when everyone arrives at once and the queue forms, rather than staffing the whole evening for a peak that lasts half an hour. The event timeline and staffing calculator handles the shift pattern side of that.
What this page deliberately does not tell you
It does not tell you how much anyone should drink, and the per-guest figures are inputs precisely so that the number belongs to you rather than to this page. It also does not tell you what is permitted. Whether you may bring your own alcohol, who is allowed to serve it, what licence covers the event and who carries liability are all set by the venue, the licence and local rules, and they differ enough that any general statement would be wrong somewhere. Ask the venue, and ask a licensed bartender or service company, before the plan depends on the answer.
Two things belong in the plan alongside the bar rather than after it: something substantial to eat, which the food per person calculator sizes, and a way for guests to get home that does not involve driving. Shuttles, rooms on site or arranged rides are part of hosting an event with a bar. For a house party rather than a catered event, the party drink calculator produces the shopping list including mixers, soft drinks and ice, which this page leaves out.
Questions people ask
How do I decide the per-guest figure to enter?
From what you know about the people coming, not from a published average. Think about a comparable evening with roughly the same group and the same food, and estimate what the first hour looked like and what the later hours looked like. The first hour is nearly always the heaviest because everyone arrives together and there is usually nothing to eat yet, which is why it is a separate field. If you genuinely have no basis for a figure, put in a range by running the page twice at a low and a high assumption and see whether the billing decision changes between them. If it does not, the assumption did not matter.
Is a package ever worth it when the numbers say no?
Yes, for a reason the arithmetic does not capture. A package converts an unknown bill into a known one, and that has value if an overrun would actually hurt — if there is no contingency left, or if the bar is the last unfixed number in the budget. Insurance costing more than the expected loss is not a reason to refuse it; it is how insurance works. The crossover figure tells you the price of that certainty, which is what you want to know before deciding whether to buy it.
Why does the cash bar route show a cost at all?
Because the host usually still pays the setup or bar fee even when guests pay for their own drinks, and that fee is the only thing on your side of the ledger. Whether it applies, and how much of it, is in the contract rather than fixed by convention. The route is included mainly so the comparison is complete. Whether a cash bar is right for your event is a hosting decision rather than a financial one, and it depends heavily on what guests will be expecting.
Do the keg serving counts allow for foam and waste?
Only partly. The figures used here — about 165 servings from a half barrel, 82 from a quarter, 55 from a sixth — are the nominal counts from the volume at twelve ounces a serving, and real pours lose some to foam, the first pull and whatever is left when the keg blows mid-service. If the count is tight, either take the next size up or plan on the last keg being partly wasted. Temperature matters more than anything else here: a keg that has not been properly chilled and settled will foam badly and lose noticeably more.
Should I include the service charge in the price per drink?
Yes, and the tax too, otherwise the comparison between routes is not like for like. A consumption bar is usually quoted at a menu price with service charge and tax added at the end, while a per-person package may or may not be quoted inclusive. Get both quotes on the same basis before entering them. The difference is often twenty to thirty percent, which is more than enough to move the crossover point across your planned quantity and flip the answer.