How Much Leg of Lamb per Person?

Plan ⅓ lb of cooked leg of lamb per adult with two or three sides — ½ lb when it's the main event — and buy raw at the 55–65% yield shown below. Kids count half.

Quick calculator — your crowd

Leg of Lamb for 10 to 100 guests

Standard scenario: adults, average appetites, two or three sides on the table. The "at the counter" column rounds up to pieces you can actually buy.

GuestsCooked meatRaw to buyAt the counter
10 3.5 lb 5–6 lb one ~6-lb bone-in leg (≈6 lb)
20 6.5 lb 10–12 lb two ~6-lb bone-in legs (≈12 lb)
25 8.5 lb 12.5–15 lb two ~7.5-lb bone-in legs (≈15 lb)
50 16.5 lb 25–30 lb four ~7.5-lb bone-in legs (≈30 lb)
100 33 lb 51–60 lb seven ~9-lb bone-in legs (≈63 lb)

The yield: raw pound ≠ served pound

A bone-in leg gives up the bone plus roast shrink: figure about 60% of raw weight serves. Boneless (netted) legs push the yield higher but lose the drama.

Buying leg of lamb: what to look for

Bone-in legs run 5–9 lb; a 7-pounder feeds ten with sides. Domestic lamb runs bigger and milder, imported (AU/NZ) smaller and more assertive. For pulled lamb, a shoulder is the better (and cheaper) cut — treat it like pork butt.

🌡️ Food safety: USDA: whole-muscle lamb is safe at 145°F with a 3-minute rest. Timing charts at 225/250/275°F: leg of lamb cook times.

Frequently asked questions

How much leg of lamb per person?

⅓ lb of cooked leg of lamb per adult when two or three sides share the table, ½ lb for hearty appetites or a meat-centered meal; kids about half. Since leg of lamb keeps only 55–65% of its raw weight, that's roughly 0.51–0.60 lb raw per adult.

How much leg of lamb for 20 people?

About 10–12 lb raw for 20 adults with a normal spread of sides — at the counter, two ~6-lb bone-in legs (≈12 lb). Scale with the chart above or the calculator for your exact crowd.

Why buy so much more raw leg of lamb than you serve?

A bone-in leg gives up the bone plus roast shrink: figure about 60% of raw weight serves. Boneless (netted) legs push the yield higher but lose the drama.

What internal temperature is leg of lamb safe at?

USDA: whole-muscle lamb is safe at 145°F with a 3-minute rest. Doneness details and hour-per-pound charts are on the leg of lamb cook-time page.