How Much Ham for 20 People?

For 20 people buy 10 lb of bone-in ham or 7 lb of boneless ham, the high end of the USDA serving (1/2 lb and 1/3 lb a person) when ham is the main dish. With plenty of other dishes, 7 lb bone-in is enough. A 10 lb whole bone-in ham reheats in 2 h 30 min to 3 h at 325°F.

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Ham to buy

10 pounds

Buy 10 lb

Servings: 20 people
Ham per servingUSDA: 1/3 to 1/2 lb of meat per serving of bone-in ham: 0.50 pounds

Reheating (oven at 325°F)

Minutes per pound, from: 15 min/lb
Minutes per pound, to: 18 min/lb
Time, shortest2 h 30 min: 150 minutes
Time, longest3 h: 180 minutes
Safe internal temperatureCooked ham packaged in a USDA-inspected plant: 140°F. It is safe cold too: 140°F

Bone-in ham, for 20 servings at 0.50 lb each. Serving sizes and minutes per pound are from the USDA FSIS timetable for ham cooked at 325°F. They are approximate, so cook to temperature with a food thermometer, not the clock. Fully cooked hams can be eaten cold; reheating is optional. The generous option is our own allowance, not a USDA figure. Discard ham left out for more than 2 hours.

Blueprint

10 lb of ham · 20 people

Ham for 20 people by serving size

The USDA allows 1/3 to 1/2 lb of bone-in ham a person, or 1/4 to 1/3 lb of boneless, because the bone is weight you buy but do not eat. Pounds are rounded up.

Serving	Bone-in ham	Boneless ham
Low end: with several other dishes	7 lb (1/3 lb each)	5 lb (1/4 lb each)
High end: ham is the main dish	10 lb (1/2 lb each)	7 lb (1/3 lb each)
Generous: with leftovers	15 lb	10 lb

Adding children

Children count as half a portion at the high USDA serving.

Guests	Bone-in	Boneless
20 adults	10 lb	7 lb
20 adults and 2 children	11 lb	7 lb
20 adults and 4 children	11 lb	8 lb
20 adults and 6 children	12 lb	8 lb

Reheating a ham for 20

Fully cooked hams at 325°F to 140°F. The USDA timetable lists each kind for a range of weights; for 20 guests the plan is a 10 lb whole bone-in ham.

Kind of ham	For 20	USDA chart weights	Time at 325°F
Cooked, whole, bone-in	10 lb	10 to 14 lb	2 h 30 min to 3 h
Cooked, half, bone-in	10 lb	5 to 7 lb (outside: check the label)	3 h to 4 h
Cooked, spiral-cut (whole or half)	10 lb	7 to 9 lb (outside: check the label)	1 h 40 min to 3 h
Cooked, boneless (vacuum packed)	7 lb	6 to 12 lb	1 h 10 min to 1 h 45 min

Twenty guests: a whole ham

Twenty guests at the high USDA serving need 10 lb, a whole bone-in ham (the chart covers 10 to 14 lb). It reheats at 325°F in 2 h 30 min to 3 h, so for dinner at 5 pm it goes in at 2:00 pm.

For leftovers the generous setting gives 15 lb, which is above the 14 lb top of the whole ham chart, so check the label for the time. Put leftovers in the refrigerator within 2 hours.

Use the ham size calculator for your own guest list, and read how much ham per person and how long to cook a ham. How long to cook a 10 lb ham has the times for every kind.

Want to change anything else? The calculator above is the full Ham Size Calculator: How Big a Ham, Bone-In or Boneless: edit any number and the results update instantly.

Tools & materials for this project

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