The 26oz does not fit in standard car or cart cupholders. Its pretty big. At a course near me with Ez-go carts, I cant even fit the 26oz in the front dash cubbies. Its great for more water, but about the only place it'll fit is in the back basket. It barely fits in the drink holder on my bag. I have had the 18 and 26 for years though and love both of them. As others mentioned, have to be careful to not get too much ice because it doesn't melt fast enough.