Spread out and enjoy more bed space by getting a California king size mattress from BJ's Wholesale Club. These extra large mattresses are 84" by 72", giving you plenty of room for great sleep. Check out big mattress brands like Sealy, Cradlesoft, Contour and many more, all priced low exclusively for Club Members. Choose your new California king size bed from a large collection boasting options with many different great features. Innerspring mattresses offer exceptional full-body support with ease of movement, while memory foam flexes and molds to your body to relieve stress on common pressure points. Get too hot at night? Try a mattress with cooling gel for a more restful night. Worried about cleanliness? Easy to clean, removable and washable covers are perfect for when your mattress needs a little TLC. No matter what kind of bed you want, BJ's Wholesale Club has a California king mattress for you.