I'm a size 14/16 and I ordered this in a size 3X/4X based off many comments that it ran small. Glad I did. Fits almost perfectly. Also, the length fits like a mini dress on a 5'6" frame. It would definitely cover you if you want to rock the tights, but I would prefer leggings as it would be really close to exposing when you sit. Will be a nice warm layer on Halloween.