I sized up to size 37 in these from my usual size 36. But I usually do that with boots anyways. These boots are suuuuper tight in the legs. They are like compression boots lol. But once they are on, they are basically like second skin. I've never had boots quite like this! They hug every curve. I think they make my ankles look super skinny and fragile though. But they do fit over skinny jeans, so that works for me. But I think that if you have calves on the thicker side, these boots would not fit even if you size up. On the other hands, if you have always felt most boots fit too loosely then these might just be perfect for you. So that's something to keep in mind. There are a few reviews for these on the Saks website that pretty much say the same thing.
I've already worn these boots a couple times! I really like them. They have a 20mm platform which is very thin. So the overall height is 120mm, but they are equivalent to a 100mm heel. That's right under 4 inches. So they are actually very comfortable. Here they are!
So as you can see in the last picture above, there is some elastic in the upper calf area. There's not a ton of stretch, but it does help a little.
I posted a picture with these boots on already, as seen here. So you can see how they look on me and how tight fitting it is in the ankles!
I do like how sleek these look though! Too bad the weather will be getting too warm for boots here pretty soon. Then I will have to wait a year to wear these! Noooo! lol.