Servers
The conventional ratios are one server per 8 to 12 guests for plated service, one per 20 to 25 for a buffet, and one per 12 to 15 for family style. Passed canapes need roughly one server per 25 guests, more if the trays are hot.
Ratios tighten for a formal event, for wine service poured at the table, and for a room spread over several levels or a long walk from the kitchen.
Bar
One bartender per 50 to 75 guests for beer and wine only, and one per 40 to 50 for a full bar. Add a barback once you pass roughly 150 guests, or once the bar is far from the ice and stock.
A second, smaller bar usually cuts the queue faster than a second bartender at the same bar.
Kitchen
Kitchen numbers depend on the menu rather than the guest count. A plated three-course dinner for 100 typically needs a chef plus three to four kitchen staff; the same 100 guests on a buffet might need a chef plus two.
Add a dedicated dishwasher for any event using real china where the venue has no kitchen porter.
The hours nobody counts
Staff hours are not the length of the party. Add loading and travel, one to three hours of setup, briefing, the service itself, then breakdown and pack-out, which is usually one to two hours.
Overtime rules, minimum call-out hours and travel time between venues are the three things most often missing from a first quote. Put them in writing before they surprise anyone.
Supervision
From about 75 guests, someone has to run the floor rather than serve on it. A captain or event lead keeps the timeline, talks to the venue and the client, and is the person the kitchen shouts at.
Below that size the head chef or the owner usually does both jobs, which works until something goes wrong.
Guide revised 18 September 2026. Figures here are planning rules of thumb, not guarantees. Send a correction.
