Will Costco Customize a Cake? The Inside Scoop on Ordering and Personalization

If you’ve ever dashed through Costco’s bakery, you know the gravity-defying towers of cakes and the scent that’s just unfair to anyone on a diet. There’s a question I hear all the time though: Will Costco actually customize a cake for your next birthday, graduation, or offbeat office party? Their cakes are famous for being tasty and wallet-friendly, but what about making them uniquely yours? Let’s dig into exactly how much creative say you really have if you’re eyeing a Costco cake for your next big event.

The Reality of Costco Cake Customization

Costco is known for keeping things efficient, and their bakery works like well-oiled clockwork. Their sheet cakes—those 40-serving monsters that party hosts love—are legendarily moist, affordable, and go for about £16 for a half-sheet (prices might nudge up or down depending on your precise location, but not by much). At that price, you have to wonder: can you really get creative control, or are you stuck with the cake equivalent of “standard issue”?

Here’s how it shakes out: Costco does offer customization, but there’s a set playbook. When you stroll up to the cake counter (or, let’s be realistic, join the queue), you’ll spot a big three-ring binder. Flip through it. You’ll see pre-set designs suited for birthdays, baby showers, graduations, and holidays. Each page shows what you can order—the cake’s base flavour (chocolate or vanilla), the decoration theme (balloons, roses, sports, and about 20 other options) and space for a short message. That’s right, you get to pick the writing on the cake, choose your icing colours, and select decorations from their workbook. But asking for a cake shaped like your dog’s head, a hyper-realistic unicorn, or a portrait of your nan? That’s not in the cards here.

So, no, you won’t get “bespoke” the way a boutique bakery might offer, but you do get reliable quality, ample size, and friendly touches that work for 90% of parties. Most folks go for this because it nails the sweet spot of affordability and reliability. As of summer 2025, the available designs and flavours still beat most supermarkets for crowd-pleasers—classic chocolate, vanilla sponge with either vanilla or chocolate mousse, generously layered with not-too-sweet buttercream. Studies show that birthday parties in the UK often have more guests than originally invited (who hasn’t had a “plus one” situation?), making that 40-slice size incredibly handy.

But if you’re after something hyper-personal—a Marvel hero, a multi-layered wedding masterpiece, or hand-piped edible works of art—you’ll want to look elsewhere. Think of Costco cakes as a solid blank canvas, with the bakery adding the basic brushstrokes and you stepping in to tweak the final scene if you’re crafty at home. Read on to see just how much you can sway the process, and the top hacks for getting the look you want.

How to Order a Customized Costco Cake

It’s surprisingly straightforward, but there’s a catch: you can’t pre-order cakes online in the UK (as of July 2025). You’ve got to do the legwork yourself—pop into your local Costco and order in-person at the bakery counter. That binder I mentioned? It’s your gateway to all things Costco cake customization.

• Step up to the bakery counter and request the design book. (If you don’t see it, just ask. The bakery staff are usually more than happy to walk people through—after all, you’re probably not the first person with a cake crisis today!)
• Flip through design choices: balloons, rainbow sprays, golf tee-offs, dozens of graduation or holiday options. For birthdays, they have designs for little ones (bears, dinosaurs), teens (soccer balls, “Happy Birthday” graffiti), and adults (elegant roses, party streamers).
• Pick your cake base—either chocolate or vanilla with their signature mousse fillings. You can’t mix and match layers or fillings, by the way. It’s a trade-off for the price and scale.
• Customise your icing colours as far as the listed palette allows. Want purple instead of blue balloons? Sure, just ask.
• Write your message on the order form. They’ll pop your greeting on with piped icing—anything from “Happy 30th, Em!” to “Congrats on the New Feline Family Member!” (That really happened—shout-out to Bristol’s most cat-loving neighbour.)
• Pick up date and time. Cakes need to be ordered at least 24 to 48 hours in advance. Don’t turn up the morning of, expecting miracles—they’re good, but not magic wizards.

For those who want a little extra, here’s a pro tip: if you want a plainer cake to jazz up at home, you can skip most decorations and just ask for a simple base with blank icing. DIYers often choose this, then add fresh fruit, branded cake toppers, edible images from online shops, or even drizzle on caramel and fudge later. Since the base cake can hold up under decorations, it’s a perfect “hack” for getting a semi-custom look but at a Costco price.

On the downside, there’s no way (yet) to order gluten-free, vegan, or highly specific allergy-friendly cakes from Costco’s core bakery range. People with celiac disease or severe allergies should steer clear or handle final decorations themselves with certified-safe toppings. Sometimes you can special order pastries or muffins for special diets, but not the classic sheet cake. So, if dietary restrictions are a must, you’ll need to go elsewhere for now.

What Costco Can (and Can’t) Customize: The Fine Print

There’s always a bit of a gap between what people think “custom cake” means and what you’ll actually get from a warehouse bakery famous for moving high volumes fast. Let’s split the wish list into what’s do-able, and where the lines are drawn.

• YES: Choose between chocolate or vanilla cake bases, with corresponding mousse fillings.
• YES: Choose a design from the book, including dozens of holiday, birthday, and occasion themes.
• YES: Customise icing colours for some designs, such as changing balloon or rose colours.
• YES: Short custom messages in piped icing. That means names, greetings, numbers, or short inside jokes.
• MAYBE: Request “no decorations” for a blank cake base, if you plan to decorate it yourself at home.
• NO: Unique artwork, such as cartoon characters not in the book, edible photos, or intricate piping beyond standard templates.
• NO: Custom flavours, fillings, or toppers that aren’t part of the set designs.
• NO: Cakes for dietary restrictions—no gluten-free, vegan, or nut-free cakes in the UK bakery range (as of July 2025).

Some Costco locations in North America have started adding edible photo cakes or offering slightly more elaborate designs if you’re willing to special order and pay up, but UK Costcos haven’t hopped on this trend yet. Always check with your local bakery—staff are open about exactly what they can do, and if you have a gentle, creative request, they’ll try to help if it’s within policy. In Bristol, for example, some bakeries have gone off the “menu” to do two-tone icing, or to add extra hearts for a charity event. The worst they can say? “Sorry, no.”

To give a sense of how the UK sizes up against other big retail bakers, here’s a quick comparison (note: data based on in-store confirmations, July 2025):

That brings us back to why so many people come back to Costco for a semi-custom cake: it may not be maximalist or one-of-a-kind, but it’s consistent, reliable, and stretches that celebration budget further than almost any other bakery option.

Clever Customisation Tips and Fun Facts for Costco Cakes

Even though Costco keeps it simple, there are ways to make those cakes look and feel more personal—and even a bit fancier—without busting the budget.

• Bring your own toppers: Order a “plain” cake, then add themed toppers from local shops or online retailers. Plenty of party planners on Instagram have turned basic Costco cakes into football stadiums, fairytale castles, or wedding-ready confections this way.
• DIY piping: If you’re handy with an icing bag, just order a cake with basic borders or flowers. At home, add extra borders, names, flourishes, or fresh flowers. It’s an easy way to own the cake moment.
• Fresh fruit upgrades: Strawberries, blueberries, raspberries—layer them across the top for extra colour and taste. The cake’s smooth buttercream top is a perfect blank slate for fresh upgrades, especially in summer.
• Chocolate, nuts, or sprinkles: Pour on caramel drizzle, chocolate pieces, or even edible glitter after pickup. Kids absolutely love rainbow sprinkles, and let’s be honest—so do grownups.
• Order early, pick up late: If your party’s on a Saturday, order by Thursday and arrange a late Friday pick-up. The cakes keep well in the fridge for 2-3 days if you want to get ahead on busy weekends.
• Check seasonal designs: Costco adds new upgrades for holidays—look out for Halloween, Christmas, or Valentine’s themes every year.

And here’s something most don’t know: Costco’s cakes freeze beautifully. If you’re hosting a combo birthday or want leftovers for another event, slice the cake into portions, wrap well, and pop in the freezer for up to three months. Plenty of parents in the Bristol area swear by this hack for stretching costs across two events.

Costco itself estimates they sell several million sheet cakes worldwide every year (last available data, 2023: nearly 7 million in North America alone). The biggest slice of the market isn’t weddings or retirements—it’s birthdays, especially for primary-age children and milestone celebrations. Nothing like a cake that feeds a football team and still leaves extras for the lunchboxes on Monday.

So, next time you’re sprinting past the bakery with a screaming toddler and a trolley full of snacks, don’t just assume you’re stuck with generic. With a bit of savvy, you absolutely can add a personal twist to your Costco cake, whether it’s with a witty inside joke piped on top or a homegrown mountain of strawberries tumbled across the buttercream. The magic, more often than not, comes from the little finishing touches you bring to the party yourself.