How much scalloped potatoes for 75 people

For 75 people, plan on 25 pounds of potatoes, which yields about 75 to 80 half-cup servings. That means roughly 1/3 pound of potatoes per person, a safe portion for a side dish. This guide gives you the exact quantities, a reliable recipe, and cost breakdown so you can cook with confidence.

The Math: Potatoes and Servings

A standard serving of scalloped potatoes is 1/2 cup cooked. One pound of raw potatoes yields about 3 cups cooked, or 6 half-cup servings. For 75 people, you need 75 servings, so:

• 75 servings ÷ 6 servings per pound = 12.5 pounds of raw potatoes.
• But add a 20% buffer for seconds and hearty eaters: 12.5 × 1.2 = 15 pounds.
• For safety, round up to 15 to 18 pounds. I recommend 18 pounds if you want leftovers or have big eaters.

Here’s a quick table for other crowd sizes:

People	Raw Potatoes (lbs)	Half-Cup Servings
25	5-6	25-30
50	10-12	50-6
0
75	15-18	75-90
100	20-25	100-125

Choosing the Right Potatoes

Use waxy or all-purpose potatoes that hold their shape when baked. Russets work but can get mushy; Yukon Gold is my go-to for flavor and texture. For 75 people, buy 18 pounds of Yukon Gold or a mix of Yukon Gold and red potatoes. Avoid starchy baking potatoes like Idaho Russets unless you prefer a softer casserole.

A Proven Recipe for 75 Servings

This recipe scales from a standard 9x13 pan (serves 12) to a large roasting pan or two half-sheet pans. The key is a rich béchamel sauce and even layering.

Ingredients

• 18 lbs Yukon Gold potatoes, peeled and sliced 1/8-inch thick (use a mandoline for even slices)
• 1 cup butter (2 sticks)
• 1 cup all-purpose flour
• 8 cups whole milk, warmed
• 4 cups heavy cream (optional for extra richness)
• 4 teaspoons salt (adjust to taste)
• 2 teaspoons black pepper
• 4 cups shredded sharp cheddar cheese (optional, but recommended)
• 1 cup grated Parmesan cheese (optional)

Instructions

1. Preheat oven to 375°F. Grease two 12x20x2-inch aluminum roasting pans (or use disposable foil pans).
2. Melt butter in a large pot over medium heat. Whisk in flour and cook for 2 minutes, stirring constantly.
3. Slowly whisk in warm milk and cream. Bring to a simmer, then reduce heat and cook until thickened, about 5 minutes. Season with salt and pepper.
4. Layer half the potatoes in each pan. Pour half the sauce over each, then sprinkle with cheddar if using. Repeat with remaining potatoes and sauce.
5. Cover with foil and bake for 45 minutes. Remove foil, sprinkle with Parmesan, and bake uncovered for 30-40 minutes more, until potatoes are tender and top is golden.
6. Let rest 15 minutes before serving.

This recipe makes about 80 half-cup servings. If you skip the cheese, it’s still creamy, just less rich.

Scaling and Timing

You can prep the casseroles a day ahead: assemble, cover, and refrigerate. Add 15-20 minutes to the covered baking time. Or bake fully and reheat in a 350°F oven for 20-30 minutes. For a crowd, cook in batches if your oven is small.

Cost Estimate for 2026

In 2026, expect to pay:

• Potatoes: $0.50 to $1.00 per pound for Yukon Gold, so 18 lbs costs $9 to $18.
• Butter: $4 to $6 per pound, you need 1/2 lb, so $2 to $3.
• Milk and cream: $4 to $6 total.
• Cheese: $8 to $12 for 4 cups of cheddar and 1 cup of Parmesan.
• Total ingredients: $23 to $39, or about $0.30 to $0.50 per serving.

If you buy pre-shredded cheese or organic potatoes, costs rise. For a budget version, use russets and skip the cream and cheese.

Tools You’ll Need

• A mandoline slicer (essential for even slices; a $20 to $40 model works fine)
• Two large roasting pans or disposable aluminum pans (about $5 each)
• A large pot for the sauce (8-quart or bigger)
• Whisk and measuring cups

FAQ

Can I use instant potatoes instead?

No, instant potatoes won’t give the same texture. Use fresh potatoes for best results.

How far ahead can I make scalloped potatoes?

You can assemble them 24 hours ahead and refrigerate. Bake as directed, adding 15-20 minutes to the covered time. Or bake fully and reheat.

Can I freeze scalloped potatoes?

Yes, freeze after baking. Cool completely, wrap tightly, and freeze for up to 3 months. Thaw in the fridge overnight and reheat at 350°F until hot.

What if I have leftovers?

Leftovers keep in the fridge for 4-5 days. Reheat in the oven or microwave. They also freeze well.

The Bottom Line

For 75 people, buy 18 pounds of Yukon Gold potatoes. That gives you about 80 half-cup servings, enough for everyone plus seconds. Use the recipe above, scale it to your pans, and you’ll have a creamy, crowd-pleasing side. Prep ahead to save time, and don’t skip the resting period before serving. With a cost of $25 to $40, it’s an affordable dish for a big gathering.