Wedding clients usually commit to a service style early. Corporate clients often don't - an HR lead might not decide between a buffet and a seated dinner until the venue and headcount are already locked, sometimes just weeks out. That means you need to be able to re-run your numbers fast when the service style changes underneath you.
Per-person quantities for the actual food don't change dramatically between buffet and plated - guests eat roughly the same amount of food either way. What changes is your buffer: buffet service typically needs a slightly larger buffer percentage, since self-serving guests are less consistent in portion size than a plated course a kitchen controls precisely.
This is the number that actually shifts hardest. Plated service needs more servers per guest for course timing; buffet needs fewer floor staff but more attention to replenishment and line management. See the staffing ratio cheat sheet for the specific numbers.
Plated service compresses your kitchen's plating window into a short, intense burst right before each course goes out. Buffet spreads the pressure out but front-loads it - everything needs to be ready and holding at the right temperature before doors open, since there's no second wave of plating to fall back on.
Buffet service needs chafing dishes, serving utensils, and a longer table setup; plated needs more plateware and a faster bussing cycle. If a client flips the service style late, don't just adjust food quantities - walk back through staffing, equipment, and timeline together, since they all move as a set.
Keep both a buffet and a plated version of your standard corporate holiday package ready to go, with the numbers pre-calculated for a few common guest counts. When the client finally decides, you're re-running a known formula, not starting over.
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