I ordered the shoe size I normally wear. These slippers were way too small. I returned the original order at my local store. I tried on a whole size larger and they fit so the store, which did not have the color I wanted, ordered the replacement and had them sipped to my home. The staff at Clackamas Town Center was superb, helpful, professional and efficient.
My dad had an old pair of these in a size 11–his shoe size is 10.5. He said they were super comfy, but I noticed that he had “walked down” the backs, and there was a little hold above his right toe, indicating to me that they were too small. To surprise him, I got another pair, this time in a 12. He initially reported that they were a bit snug, but then amended his impression, saying they did stretch out a bit with wear. So 12s were perfect for a 10.5 shoe. He loves his Uggs— but buyers should be aware they need to size up.