How much prime rib for 50 people?

For 50 guests, order about 36.3 lb of raw bone-in standing rib roast (USDA Choice), which serves about 25 lb. That is roughly 4 full trays.

How much prime rib for 100 people?

For 100 guests, order about 72.5 lb of raw bone-in standing rib roast (USDA Choice), which serves about 50 lb. That is roughly 7 full + 1 half trays.

Catering portion guide

How much prime rib per person?

In short

Plan on an 8 oz (1/2 lb) carved cooked portion per person for a formal dinner. For bone-in standing rib roast, purchase roughly 12 oz raw per guest (1 bone per 2 guests): 50 guests requires about 38 lb raw roast (approx 25 ribs across 3-4 whole roasts).

Buy more prime rib than you serve

A bone-in standing rib roast loses 25% to 30% to bone and fat cap trimming plus oven rendering. Boneless roasts run closer to 1.25x yield.

Planning factor: 1.45x. For every 1 lb you want to serve, order about 1.45 lb of raw bone-in standing rib roast (USDA Choice).

How much prime rib for 10 to 100 people

Order is what to buy as raw bone-in standing rib roast (USDA Choice). Serves is what reaches the plate after trim and cooking.

Prime Rib quantities by guest count, showing purchase weight and served weight
Guests	Order	Serves	Trays
8	5.8 lb	4 lb	1 full tray
10	7.3 lb	5 lb	1 full tray
12	8.7 lb	6 lb	1 full tray
15	10.9 lb	7.5 lb	1 full + 1 half trays
16	11.6 lb	8 lb	1 full + 1 half trays
20	14.5 lb	10 lb	1 full + 1 half trays
24	17.4 lb	12 lb	2 full trays
25	18.1 lb	12.5 lb	2 full trays
30	21.8 lb	15 lb	2 full + 1 half trays
40	29 lb	20 lb	3 full trays
50	36.3 lb	25 lb	4 full trays
60	43.5 lb	30 lb	4 full + 1 half trays
75	54.4 lb	37.5 lb	5 full + 1 half trays
100	72.5 lb	50 lb	7 full + 1 half trays

These are standard food-service planning figures, not fixed constants. Real yield moves with cut, trim level, cooking method, and how long the food is held. Weigh your own results once and adjust the factor to your kitchen.

Things that change the number

For boneless prime rib, purchase 10 oz raw per guest instead of 12 oz.
Carve at the station under a heat lamp to control portion size and maintain temperature.
Collect all au jus pan drippings for service; prime rib without au jus dries out quickly.

Common questions

How much prime rib per person?: Plan on an 8 oz (1/2 lb) carved cooked portion per person for a formal dinner. For bone-in standing rib roast, purchase roughly 12 oz raw per guest (1 bone per 2 guests): 50 guests requires about 38 lb raw roast (approx 25 ribs across 3-4 whole roasts).
How much prime rib for 50 people?: For 50 guests, order about 36.3 lb of raw bone-in standing rib roast (USDA Choice), which serves about 25 lb. That is roughly 4 full trays.
How much prime rib for 100 people?: For 100 guests, order about 72.5 lb of raw bone-in standing rib roast (USDA Choice), which serves about 50 lb. That is roughly 7 full + 1 half trays.

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