UPDATE: If you are in the US, please use the newer version of the order form that I have posted here. It was updated in 2011 to account for the changes to the cake selections (like, no carrot cake or cupcakes and fewer icing and filling options).
One of the friendly Costco Bakery folks commented (on Costco Bakery Makes an Excellent Cake) a while back that the sheet cake and cupcake order form for the US had been updated, so the one I had posted was no longer valid. Apparently, this was to account for changes to filling and icing choices that Costco has put into effect. So, when we were in New York I picked up the new order form so I could share it with everyone here. I still don’t understand why they don’t have a copy of this on the Costco.com website, but I’ll fill in the gap. I’m also going to take this opportunity to add the UK cake order form to the site, as well.
The order form is pretty self-explanatory and pretty clearly lists all choices. The order form for the US Costco locations lists prices: $16.99 for white or chocolate cake and 20 pack of cupcakes; $18.99 for a Carrot Cake. It is also nice enough to let you know that there are 48 servings per cake. The UK order form does not list prices, though the cakes are always £11.99 when I have looked at them previously. Also, in the UK you can still mix and match your cake, filling and icing choices. However, no carrot cake option here in the UK. Also, in the US you just need to give them 24 hours of advanced notice but here in the UK they require at least 48 hours advanced notice.
Since you can fax the order forms to the Costco Bakery location of your choosing, you should now be able to handle ordering without a special trip to Costco. And, if you missed it, I did post images of the US Costco cake designs. I’ll try to get something similar for the UK designs as well. Just click on the image below to get the full-sized order form.