I'm 5'3 and bought the size S and it fit. I feel like I could have fit both the XS or S. The fabric seems quite stretchy. I don't know how to describe it. It's like loose but fitted around the chest. having said that, I'm quite happy with the S since I can now layer thicker tops underneath. I think the XS would be overall tighter. I can also totally see myself wear this dress with some thick stockings and a nice leather jacket. Dress is very soft. Definitely a luxy comfy look. It's not as bulky as I initially thought it would be. I'm pretty happy with the turnout.