I’m 5’5 and 137lbs. I usually wear medium and I am small chested. I ended up ordering Large cause that was all they had and I really wanted this outfit. If it was too big, I was going to just get it altered. It came in and I tried it on, it fit me perfectly. I do have a booty tho and if I bend over, my cheeks would show. I like how the large fit me and covered me nicely enough. I was really surprised it fit me so good and even the arm piece fit me perfectly, that’s why I say this runs a bit small. Overall, good material, super freakin cute and I tied the strings and cut the excess off. They’re SO LONG! I didn’t tie it exactly like the pic since I couldn’t figure it out but I like how i tied it. I wish I can post my pic! The outfit is so cute and I got so many compliments!