I'll be honest — the first graduation open house I helped host, I made about four trips to Costco in the days leading up to the party. Forgot the buns. Forgot ice. Forgot napkins. Underbought drinks. Overbought paper plates by approximately a thousand.

Since then, I've planned and helped plan enough parties to know that Costco is genuinely the easiest place to feed a crowd — but only if you know exactly what to buy before you walk in.

This is the list I wish I'd had on my first trip. Real prices, real Costco brands, real quantities scaled for 25 to 100 guests. Three menu styles (taco bar, BBQ, sandwich open house) so you can pick what fits your party. And a calculator at the bottom so you can plug in your exact guest count and get your shopping list instantly.

No fluff. Just the list.

Jump to:

• Quick Answer: What to Buy at Costco for 50 Graduation Guests
• Tell me about your crowd
• What's your menu style?
• What to include?
• Your Costco Shopping List
• How Much Does a Costco Graduation Party Cost?
• Why Costco Wins for Graduation Parties
• Costco Graduation Party Shopping Lists by Guest Count
• Menu Variations: Beyond the Taco Bar
• Drinks at Costco for a Graduation Party
• Don't Forget the Ice
• Biggest Costco Graduation Party Mistakes
• Real Graduation Party Budget Examples
• FAQ
• Final Thoughts
• Related
• Pin to Pinterest

Quick Answer: What to Buy at Costco for 50 Graduation Guests

For a 50-guest graduation party with a taco bar menu at Costco, you'll need roughly:

• 11 lbs ground beef + 5 rotisserie chickens (the dual-protein move)
• 7 packs of flour tortillas + 2 packs of corn
• 3 bags shredded cheese, 3 jars salsa, 2 tubs sour cream, 2 packs guacamole
• 2 fruit/meat/cheese platters (the secret weapon)
• 1 half-sheet cake + 1 tray of cookies
• 3 cases of water, 1 Coke, 1 Diet Coke, lemonade, sparkling water
• Paper plates, napkins, cutlery, cups (one pack of each covers it)

Total cost: ~$489 (about $9.78 per person)

Want exact amounts for your guest count and menu? Use the calculator below.

How Much Does a Costco Graduation Party Cost?

Here's the at-a-glance budget breakdown across all three menu styles. Use this to pick your menu, then scroll to the full shopping list for that combo.

Guests	🌮 Taco Bar	🥪 Sandwich Open House	🍔 BBQ + Burgers
25	$324	$311	$339
50	$489	$445	$532
75	$665	$580	$737
100	$863	$746	$970

All totals exclude ice — use the ice calculator for that. Drinks, desserts, and paper supplies included.

A few quick takeaways from this table:

• The sandwich open-house menu is the cheapest at scale. At 100 guests, it's $117 less than taco bar and $224 less than BBQ.
• Taco bar is the sweet spot for variety, cost, and crowd appeal — which is why it's the default in this guide.
• BBQ is the most expensive at every guest count because of the dual proteins and buns.
• Per-person cost drops fast as you scale — a 100-guest taco bar runs about $8.63/person versus $12.98/person for 25.

Why Costco Wins for Graduation Parties

A few reasons Costco beats almost every other option for open-house style grad parties:

Bulk pricing actually scales. A regular grocery store charges you near-retail for party quantities. Costco's per-unit pricing genuinely drops at the sizes you need — especially on meat, cheese, drinks, and bakery items.

The fresh-prepared trays are massively underrated. Costco's artisan sandwich platter, croissant chicken salad platter, and fruit/meat/cheese platter each feed 18–24 people for under $50. That's $2 per serving for finished food you didn't have to make.

Fewer trips. Most of what you need is in one warehouse. You can do produce, protein, bakery, drinks, and paper goods in a single run — which matters when you're already stressed about everything else.

Open-house friendly. Costco party food handles 3–4 hours of guests trickling in and out without falling apart. Trays hold, drinks stay cold, desserts don't melt.

One honest note: Costco becomes especially cost-efficient once you're feeding 40+ people. For smaller parties (25 or fewer), you'll have meaningful leftovers because of minimum pack sizes. Most grad party hosts I know consider that a feature, not a bug — but it's worth knowing going in.

For the full party portion math beyond just Costco, the graduation party food guide covers exact amounts for any menu, not just Costco-specific.

Costco Graduation Party Shopping Lists by Guest Count

These lists assume a typical 3–4 hour graduation open house where guests graze throughout the event rather than sitting down for one plated meal.

These lists default to a taco bar menu (the most popular grad party format), with menu variations further down. Every quantity below includes a 10% safety buffer because running out of food is the #1 graduation party regret.

Shopping List for 25 Guests (~$324 total)

Mains (taco bar):

• 6 lb Kirkland ground beef — $35.94
• 3 Costco rotisserie chickens — $14.97
• 4 packs Mission flour tortillas (80 tortillas total) — $14.78
• 1 pack Guerrero corn tortillas (55 total) — $2.50
• 2 bags Kirkland shredded Mexican cheese — $13.49
• 2 jars Jack's Cantina salsa — $13.98
• 1 tub Dairy Gold sour cream — $4.89
• 1 x Wholly Guacamole 3-pack — $13.99
• 1 bag Kirkland tortilla strips — $4.99

Sides:

• 1 Kirkland Fruit, Meat & Cheese Platter — $39.99
• 1 Lay's variety pack (30-count) — $19.49

Desserts:

• 1 Costco 10" round cake (serves 16) — $17.99
• 1 tray Costco chocolate chip cookies (24) — $9.99

Dessert coverage at this size assumes typical open-house grazing — not every guest takes both cake and cookies. If you want a generous buffer, add a tray of brownies or extra cookies from home.

Drinks:

• 2 cases Kirkland water (80 bottles) — $7.98
• 1 case Coca-Cola (35 cans) — $17.99
• 1 case Diet Coke (32 cans) — $17.99
• 1 Kirkland organic lemonade 2-pack — $6.79
• 1 case Kirkland flavored sparkling water — $10.99

Supplies:

• 1 pack Kirkland paper plates (225) — $17.79
• 1 pack Kirkland napkins (1,120) — $11.99
• 1 pack Kirkland plastic cutlery (360) — $14.99
• 1 pack Kirkland plastic cups (240) — $10.89

Estimated total: $324

Shopping List for 50 Guests (~$489 total)

Mains (taco bar):

• 11 lb Kirkland ground beef — $65.89
• 5 Costco rotisserie chickens — $24.95
• 7 packs Mission flour tortillas (140 total) — $25.87
• 2 packs Guerrero corn tortillas (110 total) — $4.99
• 3 bags Kirkland shredded Mexican cheese — $20.24
• 3 jars Jack's Cantina salsa — $20.97
• 2 tubs Dairy Gold sour cream — $9.78
• 2 x Wholly Guacamole 3-pack — $27.98
• 2 bags Kirkland tortilla strips — $9.98

Sides:

• 2 Kirkland Fruit, Meat & Cheese Platters — $79.98
• 2 Lay's variety packs (60 bags total) — $38.98

Desserts:

• 1 Costco half-sheet cake (serves 48) — $27.99
• 1 tray Costco chocolate chip cookies — $9.99

Drinks:

• 3 cases Kirkland water (120 bottles) — $11.97
• 1 case Coca-Cola — $17.99
• 1 case Diet Coke — $17.99
• 1 Kirkland organic lemonade 2-pack — $6.79
• 1 case Kirkland flavored sparkling water — $10.99

Supplies:

• 1 pack Kirkland paper plates — $17.79
• 1 pack Kirkland napkins — $11.99
• 1 pack Kirkland plastic cutlery — $14.99
• 1 pack Kirkland plastic cups — $10.89

Estimated total: $489

This is the sweet spot for Costco grad parties. Per-person cost lands around $9.78 — significantly cheaper than catering, and you don't have to cook anything from scratch.

Shopping List for 75 Guests (~$665 total)

Mains (taco bar):

• 17 lb Kirkland ground beef — $101.83
• 7 Costco rotisserie chickens — $34.93
• 11 packs Mission flour tortillas (220 total) — $40.64
• 3 packs Guerrero corn tortillas (165 total) — $7.49
• 4 bags Kirkland shredded Mexican cheese — $26.98
• 4 jars Jack's Cantina salsa — $27.96
• 2 tubs Dairy Gold sour cream — $9.78
• 3 x Wholly Guacamole 3-pack — $41.97
• 3 bags Kirkland tortilla strips — $14.97

Sides:

• 2 Kirkland Fruit, Meat & Cheese Platters — $79.98
• 3 Lay's variety packs — $58.47

Desserts:

• 1 Costco half-sheet cake — $27.99
• 2 trays Costco chocolate chip cookies (48 cookies) — $19.98

Drinks:

• 4 cases Kirkland water (160 bottles) — $15.96
• 2 cases Coca-Cola (70 cans) — $35.98
• 1 case Diet Coke — $17.99
• 2 Kirkland organic lemonade 2-packs — $13.58
• 2 cases Kirkland flavored sparkling water — $21.98

Supplies:

• 1 pack Kirkland paper plates — $17.79
• 1 pack Kirkland napkins — $11.99
• 1 pack Kirkland plastic cutlery — $14.99
• 2 packs Kirkland plastic cups — $21.78

Estimated total: $665

Shopping List for 100 Guests (~$863 total)

Mains (taco bar):

• 22 lb Kirkland ground beef — $131.78
• 9 Costco rotisserie chickens — $44.91
• 14 packs Mission flour tortillas (280 total) — $51.73
• 3 packs Guerrero corn tortillas — $7.49
• 5 bags Kirkland shredded Mexican cheese — $33.73
• 5 jars Jack's Cantina salsa — $34.95
• 3 tubs Dairy Gold sour cream — $14.67
• 4 x Wholly Guacamole 3-pack — $55.96
• 4 bags Kirkland tortilla strips — $19.96

Sides:

• 3 Kirkland Fruit, Meat & Cheese Platters — $119.97
• 4 Lay's variety packs — $77.96

Desserts:

• 2 Costco half-sheet cakes (serves 96 total) — $55.98
• 2 trays Costco chocolate chip cookies (48 cookies) — $19.98

Drinks:

• 5 cases Kirkland water (200 bottles) — $19.95
• 2 cases Coca-Cola — $35.98
• 2 cases Diet Coke — $35.98
• 2 Kirkland organic lemonade 2-packs — $13.58
• 2 cases Kirkland flavored sparkling water — $21.98

Supplies:

• 1 pack Kirkland paper plates — $17.79
• 1 pack Kirkland napkins — $11.99
• 1 pack Kirkland plastic cutlery — $14.99
• 2 packs Kirkland plastic cups — $21.78

Estimated total: $863

At 100 guests, your per-person cost drops to just $8.63 — under $9 per head for a fully-stocked party with drinks, desserts, supplies, and a real meal. That's why Costco wins for bigger parties.

Menu Variations: Beyond the Taco Bar

Taco bar is the default because it's the most popular and most flexible — but two other menu styles work great at Costco for grad parties.

🍔 BBQ + Burgers Menu Variation

Classic graduation BBQ with both burgers and hot dogs (the dual-protein approach most grad parties use). More expensive than tacos because of the dual proteins, the buns, and larger cooked meat portions per adult — but undeniably crowd-pleasing.

What changes from the taco bar list:

• Swap ground beef quantity (still Kirkland, but now for burgers — about ⅓ lb per adult)
• Add Kirkland beef hot dogs (3-packs of 12, ~$19.39 per 3-pack)
• Add Franz hamburger buns ($4.99 / 12-count)
• Add Seattle International hot dog buns ($4.99 / 16-count)
• Add Kirkland mac & cheese as the signature side ($3.99 / ~4 lb)
• Skip the tortillas, cheese, salsa, sour cream, and guac

Budget by guest count:

Guests	Total Cost	Per Person
25	~$339	$13.56
50	~$532	$10.63
75	~$737	$9.83
100	~$970	$9.70

For exact portion math, use the hot dogs per person guide and burgers per person guide.

🥪 Sandwich Open House Menu Variation

The lowest-effort, lowest-cost option — and surprisingly the best value at scale. This is the menu I recommend for hosts who want minimal day-of work.

What changes:

• Costco artisan sandwich platter ($49.99 each, serves 18-20)
• Kirkland croissant chicken salad platter ($44.99 each, serves ~18)
• Mix and match platters by guest count for variety
• Kirkland chicken salad tub for refills ($5.99 / 3 lb)
• Skip the proteins, tortillas, toppings entirely

Budget by guest count:

Guests	Total Cost	Per Person
25	~$311	$12.43
50	~$445	$8.91
75	~$580	$7.74
100	~$746	$7.46

At 100 guests, the sandwich open-house build is $117 cheaper than tacos and $224 cheaper than BBQ. If budget matters most, this is your menu.

Drinks at Costco for a Graduation Party

Drinks math is straightforward — plan on 3 drinks per person across a 3-4 hour open house. That breaks down to roughly:

• 50% water (Kirkland 40-pack is the workhorse — $3.99 per case)
• 30% soda (split between Coca-Cola and Diet Coke)
• 10% lemonade (Kirkland organic lemonade 2-pack — $6.79)
• 10% sparkling water (Kirkland flavored 24-pack — $10.99)

A few hard-earned tips:

Buy more water than you think. If your party is outdoors and the weather warms up (likely for May/June graduations), you'll go through 2x the water you expected. Stock heavier on water than soda.

Skip the lemonade jugs at small parties. For 25 guests, one lemonade 2-pack is plenty. Don't over-buy — it's the drink most likely to get left over.

Sparkling water is the surprise hit. Adults love having something fizzy that isn't soda. One case of variety pack flavors gets demolished.

For exact drink math by event length and guest count, see the drinks per person guide.

Don't Forget the Ice

Ice is one of the most underbought items at every graduation party. The amount you need depends on weather, drink type, whether you're using a cooler vs. just keeping things cold, and whether you also need ice for keeping platters cold.

Rather than slap a generic number here, I built a dedicated calculator that handles all those variables.

→ Use the ice calculator to get your exact bag count.

Also worth knowing: not every Costco warehouse sells ice. Check yours before relying on it — some stock 16-lb bags for around $2.49, but availability varies.

Biggest Costco Graduation Party Mistakes

I've made or watched friends make every one of these. Save yourself the trip back to the store.

1. Not buying enough drinks. This is the most common, by a wide margin. Three drinks per person is a safe baseline — for outdoor parties or warm weather, bump it to four.

2. Buying too many desserts. Open-house guests eat less dessert than you'd think (many are headed to multiple grad parties). One Costco half-sheet cake plus a tray of cookies covers 50 guests with leftovers. Don't add cupcakes "just in case."

3. Forgetting serving utensils. Costco's combo cutlery pack covers forks and spoons, but you also need tongs for the taco meat, serving spoons for sides, and a cake knife. Buy them or pull from home before the day-of.

4. Underestimating ice. See above — use the ice calculator. Most hosts underbuy by 50%.

5. Buying too much of one platter. Costco sandwich platters are huge. Two artisan platters cover 38 servings — that's a lot. Add a smaller croissant chicken salad platter instead of a third artisan for variety.

6. Forgetting the buns at home. Sounds dumb. Happens constantly. If you're doing the BBQ menu, set the buns next to your keys the morning of.

7. Not accounting for open-house flow. Graduation parties are drop-in style. Guests come and go over 3-5 hours. Keep half your food in reserve and replenish — don't put everything out at once or it'll look picked-over by hour two.

Real Graduation Party Budget Examples

Three real-world Costco-only budgets, scaled to common grad party sizes:

🥪 Tight Budget — Open House for 50 Guests: $445 The sandwich platter route. Two artisan sandwich platters, one croissant chicken salad platter, a fruit/meat/cheese platter, chips, half-sheet cake, drinks, supplies. About $8.91 per person. Lowest effort, lowest cost.

🌮 Mid-Range — Taco Bar for 50 Guests: $489 The default crowd-pleaser. Ground beef + rotisserie chicken, full taco toppings bar, fruit/meat/cheese platter, half-sheet cake, drinks, supplies. About $9.78 per person.

🍔 Big BBQ — Burger Cookout for 75 Guests: $737 The classic dad-grilling-burgers grad party. Burgers and hot dogs, both buns, mac & cheese, fruit/meat/cheese platter, half-sheet cake, drinks, supplies. About $9.83 per person.

All three numbers exclude ice (use the ice calculator for that) and assume you already have basic serving utensils.

FAQ

How much should I budget per person for a Costco graduation party? Plan on roughly $9–$14 per person, depending on menu style and guest count. Smaller parties (25 guests) run closer to $13 per person because of minimum pack sizes. Larger parties (75-100 guests) drop to $8–10 per person because bulk pricing kicks in.

Is Costco actually cheaper than other grocery stores for parties? For protein, bakery, drinks, and paper goods — yes, by a meaningful margin. For produce and small specialty items, it's about even. The biggest savings are on bulk meat (ground beef family pack), the bakery (half-sheet cakes), drinks (40-pack water), and paper supplies.

How many Costco rotisserie chickens do I need for 50 guests? For a taco bar where chicken is half the protein (the other half being ground beef), plan on 5 rotisserie chickens for 50 guests. Each chicken yields about 2 lbs of pulled meat. If chicken is your only protein, you'd need 8-10 chickens for 50 guests.

How many Costco half-sheet cakes for 100 guests? Two half-sheet cakes cover 100 guests with leftovers. Each Costco half-sheet serves 48. For variety, you can do one half-sheet plus one 10" round cake instead, or add a tray of cookies on the side.

Does Costco sell ice at every warehouse? No — availability varies by location. When stocked, Kirkland ice is sold in 16-lb bags for around $2.49. Check your local warehouse before the day of, and have a backup plan (most gas stations sell ice for similar prices).

Can I order Costco platters in advance? Yes, and you should. Most Costco deli platters require 24-48 hours advance order. Call your warehouse's deli or order through the Costco app a few days before the party.

What about Costco Business Center? If there's a Costco Business Center within driving distance (Utah has them in Salt Lake), check their bulk meat and dessert pricing. Some items are cheaper there, especially for parties of 75+ guests.

How do I know how much taco meat for 100 guests? The math: 100 guests × 0.3 lb cooked meat = 30 lbs cooked. Since ground beef cooks down to about 75% of raw weight, that's 40 lbs raw beef if it's your only protein — or roughly 20 lbs raw beef plus 8 rotisserie chickens if you're doing the dual-protein approach. For exact calculations, use the taco bar portions guide.

Final Thoughts

The hardest part of a graduation party isn't the cooking or the setup. It's the planning — the not-knowing-what-to-buy that turns one Costco trip into three.

This list exists so you can do one trip, with confidence, and spend the rest of the week actually celebrating your graduate instead of stressing over whether you bought enough hamburger buns.

The calculator above gives you your exact list for your exact guest count. The menu variations let you pick the style that fits your family. And the budgets give you a real number to plan around — no guessing.

You've got this. Your graduate is going to remember the party because you were present, not because you served the perfect amount of guacamole.

If you want help planning the rest of it, my graduation party food guide walks through everything beyond just Costco — and the ultimate party food planning guide covers the bigger picture if you're hosting multiple events this season.

Now go make the list. The party is going to be great.

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