The quantity rules caterers use

Catering math is remarkably consistent across the industry. For cocktail hour, plan 4–6 passed appetizer pieces per guest; if hors d’oeuvres replace dinner entirely, that jumps to 12–15 pieces per guest with heavier, more substantial bites. For a dinner buffet, the working rule is about 1.25 lb of food per adult across the whole plate: 6–8 oz of protein, two sides, salad and bread. Family-style needs roughly 15% more than plated (platters must look generous when they land), and buffets need more than both because guests serve themselves.

For cake, the classic planning number is one slice per adult, minus about 15% — some guests skip dessert, and if you add a dessert bar, cake consumption drops to about 60%. A dessert bar on its own should offer 2–3 small pieces per guest across at least three options.

Where couples over- and under-buy

• Over: dinner rolls, salad, and cake for a crowd that’s been eating for four hours. The top tier of your cake traditionally comes home with you anyway.
• Under: cocktail-hour appetizers (hungry guests + open bar is a bad combination) and late-night snacks — after two hours of dancing, expect 2 out of 3 guests to reappear at a food table. Pizza, sliders and fries vanish fastest.
• Kids eat half. Most caterers price children under 12 at half portions — order accordingly, and ask for the kids’ meals to come out first.
• Vendors eat too. Add a meal for each photographer, videographer, DJ, planner and band member — usually at a reduced “vendor meal” rate.

Use these numbers to sanity-check caterer proposals or plan a DIY/family-catered wedding — then confirm final counts with whoever’s cooking two weeks out.