For a 100-person office party, plan on roughly 150 to 200 drinks — about one 1/2 barrel keg (it pours around 165 twelve-ounce glasses) plus a smaller backup, or two 1/2 barrels if it is a long evening or a thirsty crowd. That is the short answer. The right number depends on how long the party runs, how many guests actually drink, and whether you put more than one beverage on tap. Here is how to size it without over- or under-ordering.
How many drinks will 100 people actually have?
A common planning rule is one drink per guest in the first hour and one more each hour after. For a typical two-to-three-hour office party, that lands around 150 to 200 servings for 100 people — not 300. Office crowds skew lighter than a wedding or a bar: some guests do not drink, others have one and switch to water or cold brew. If your team historically drinks hard on a Friday, plan toward the top of that range; for a mixed afternoon reception, the lower end is usually plenty.
How many kegs is that?
One 1/2 barrel covers a standard 100-person office party, with a 1/6 barrel as backup insurance. Match the keg size to the servings you need:
| Keg size | Volume | ~12 oz pours | Good for |
|---|---|---|---|
| 1/2 barrel (full keg) | 15.5 gal | ~165 | a 100-person party on its own |
| 1/4 barrel (pony) | 7.75 gal | ~82 | about 50 guests, or a second style |
| 1/6 barrel (sixtel) | 5.16 gal | ~55 | a backup or a variety tap |
So the cleanest setups for 100 people are: one 1/2 barrel (simple, covers a lighter crowd), one 1/2 barrel plus a 1/6 backup (the safe pick), or two 1/2 barrels if you expect heavy pours or a long event. Browse the full keg selection to see what is available by size.
One big keg, or a few smaller ones?
If variety matters more than simplicity, two or three 1/6 barrels of different styles beat a single 1/2 barrel. A hazy IPA, a crisp lager, and a non-alcoholic option give your team real choice and keep any one line from running dry at the wrong moment. The tradeoff is taps: each keg needs its own tap, so a multi-keg setup means a multi-tap kegerator or a couple of jockey boxes. For a once-a-quarter party, one 1/2 barrel on a single tap is the lower-effort win.
Do not forget the people who are not drinking
Put at least one non-alcoholic option on tap or on ice so nobody is left out. Cold brew coffee and kombucha both come in kegs and run on standard draft equipment, so you can pour them right alongside the beer. They also make the party work at 3 p.m., not just after five.
How Mike's gets it to your office
Mike's Beverages and Liquors has been the Bay Area's keg headquarters from our shop at 5084 Mission St since 1959, and we set up San Francisco offices for parties every week. We deliver same-day in San Francisco for orders placed by 9 a.m., with scheduled East Bay (Tuesdays) and South Bay (Wednesdays) runs, and we can supply the tap, CO2, and jockey box along with the keg. We handle the refundable keg deposits and swap empties, so the only thing your team has to plan is who brings the speaker. For recurring setups, ask about our office beverage program. New to this? Our guide on how to pick a keg for your office party covers the styles that please the widest crowd.
Ready to order? Tell us your headcount and the date, and we will size the kegs and the gear so nothing runs dry.
How far in advance should I order kegs for an office party?
A few days is usually enough, and same-day delivery is available in San Francisco for orders placed by 9 a.m. Popular kegs and specific styles can sell out, so reserve about a week ahead when you can, especially around the holidays.
Do I need a tap and CO2, or just the keg?
You need a way to pour: a kegerator, a tap-and-CO2 setup, or a jockey box for a one-off party. Mike's rents the equipment alongside the keg, so you do not have to own anything — just tell us how many taps you need.
What happens to the empty keg and the deposit?
Return the empty keg and your refundable $50 deposit comes back. Mike's picks up empties on the delivery runs, so for a scheduled office order it is hands-off: we drop the full keg and take the empty.