I usually wear an 11 in FN Jeans. I purchased a 9 based off of reviews. Very comfy. Hips 42in. Waist 35. If your waist is smaller by an inch or 2 I think a 9 will still fit nicely.. maybe you can size down 1 size if your waist is smaller than that. If your hips are bigger by an inch or 2 I think it will still fit comfortably. Depends on how tight your like your jeans. They have a good amount of stretch through out the pants