Costco Cake Servings – How Many People Does Each Cake Feed?

If you’ve ever stared at a Costco cake and wondered whether it will cover your guest list, you’re not alone. The good news is that Costco’s cakes follow a pretty predictable sizing system, so you can match the right cake to any party without eyeballing it.

Understanding Costco Cake Sizes

Costco offers three standard round cakes and two sheet options. Here’s the quick cheat sheet:

• 8‑inch round – About 20‑24 servings. Each slice is roughly 2" x 2".
• 9‑inch round – Around 30‑35 servings. You’ll get slightly larger pieces, about 2.5" x 2".
• 10‑inch round – Approximately 45 servings. Perfect for bigger gatherings.
• Full sheet (12" x 18") – Roughly 72 servings, cut into 2" x 2" squares.
• Half sheet (12" x 9") – About 36 servings, same square size.

These numbers assume adult portions. If you’re serving a crowd of kids, you can stretch each cake a bit further because smaller plates mean smaller bites.

Tips to Get the Perfect Portion

1. Measure your slice. A 2" x 2" piece is the industry standard for one serving. If you cut larger, plan for fewer people.

2. Consider the event. Weddings or formal dinners often call for generous slices, while a casual brunch can get away with smaller pieces.

3. Round up. It’s always safer to order a cake that serves a few extra guests. Leftover cake is rarely a problem, and most people love a second helping.

4. Ask the bakery staff. Costco’s bakers can give you a quick estimate based on the number of guests you tell them. They’re used to these questions and can suggest a size that fits your budget.

5. Combine cakes. If you’re unsure about a single size, you can order two smaller cakes. This gives you flexibility in flavor choices and makes cutting easier.

6. Think about frosting. Heavier frosting adds calories, so if you’re feeding health‑conscious guests, a lighter buttercream might let you serve a bit more without overloading anyone.

7. Plan for leftovers. Store any extra slices in an airtight container in the fridge for up to three days, or freeze them for a longer stash. They taste great toasted with a dab of butter.

By keeping these pointers in mind, you’ll never second‑guess a Costco cake order again. Whether it’s a birthday, a potluck, or a corporate lunch, you now have the numbers to match the cake to your guest count confidently.

So next time you head to the bakery aisle, pick up that cake with the peace of mind that it will feed everyone—plus maybe a few extra happy mouths.