Yes, I believe that most are heated. When we were at AllStars last Dec (12-17) there were people in the pool. You could see the steam coming off it. I'm sure the kids were quite warm in the water, but they had to come out at some point!!! We've been in early Nov and the weather was terrific. No problem swimming at all. We're going again over Thanksgiving so hoping that the weather is warm enough to get out of the pool and not freeze!!