How Many People Can a Costco 1/2 Sheet Cake Feed? Portion Size & Serving Guide
Wondering how many people a Costco 1/2 sheet cake can actually feed? Find out portion sizes, serving tips, and cake facts that will save your next big party.
How to Choose the Right Costco Cake Size for Your Event
Planning a birthday, graduation, or any celebration? One of the biggest decisions is figuring out how big a cake you need. Costco makes the choice easy with a few standard sizes, but you still have to match the cake to your guest list and budget. This guide breaks down the options, tells you how many people each size feeds, and gives quick tips so you don’t end up with leftover frosting or a tiny slice for a big crowd.
What Sizes Does Costco Offer?
Costco’s bakery typically stocks three round cakes and a few sheet options. The round cakes come in 8‑inch, 10‑inch, and 12‑inch diameters. An 8‑inch cake is about 1.5 lb and serves roughly 12‑15 guests. The 10‑inch version weighs around 2.5 lb and feeds 20‑25 people. The biggest round, 12‑inch, is close to 3.5 lb and can handle 30‑35 servings. If you need a flatter, larger surface for lots of cupcakes or a big logo, Costco also sells a half‑sheet (about 9×13 in) and a full sheet (about 12×18 in). A half‑sheet usually serves 24‑30, while a full sheet can cover 50‑60 guests.
How to Match Cake Size to Your Guest List
First, count the people you’ll serve. For adults, plan on one slice each; for kids, half a slice often works. Next, decide if you want extra cake for seconds or a safety margin—most bakers add 10‑15 % extra to avoid running short. For example, a party of 22 adults would need about 25 servings. A 10‑inch round (20‑25 servings) would be tight, so upgrading to a 12‑inch round or a half‑sheet gives room to breathe.
If you’re serving other desserts, you can size down. A dessert table with cupcakes, cookies, and fruit might let you cut the cake count in half. In that case, a 12‑inch cake could comfortably serve a crowd of 40 when other sweets fill the gaps.
Don’t forget the shape you want. Round cakes look classic, but sheet cakes are easier to cut into uniform squares and give more surface for writing or decorations. Costco’s sheet cakes also tend to be cheaper per serving, making them a smart pick for large gatherings.
When you place your order, call the bakery at least 24 hours ahead. Let them know the exact size, flavor, and any icing or message you need. Costco usually has a standard selection of flavors—chocolate, vanilla, and red velvet—but you can ask for a custom frosting color for a small extra fee.
Here’s a quick cheat sheet:
- 8‑inch round: 12‑15 servings – small family or intimate party.
- 10‑inch round: 20‑25 servings – typical birthday or office lunch.
- 12‑inch round: 30‑35 servings – medium‑large celebration.
- Half‑sheet: 24‑30 servings – great for mixed desserts.
- Full sheet: 50‑60 servings – perfect for big events or corporate gatherings.
Pick the size that covers your guest count, adds a little wiggle room, and fits your budget. With these basics, you’ll avoid the dreaded “who gets the last slice?” moment and enjoy a stress‑free celebration.
