A 10 petite is usually a safe bet for me. I have JJill pants in authentic fit in an 8 petite, and the denim crops from last yr in a 8 reg., and even a 6 reg in the boyfriend style jeans. All of that to compare if you have any of those too. I thought the 10 petite would give me a bit of breathing room as I gained a bit of weight over the winter that I am still trying to lose, and figured the poplin would shrink over time anyway. These are surprisingly a bit tight in the backside! I am very hourglass shaped with a round rear end and on the cusp of petite. Waist was perfect and hit at my navel. To compare I am 5'3'', 134 pounds, waist 28, hips 39. I will keep these, line dry and motivate myself harder in the gym. Hope this helps! they are a nice lightweight fabric, and a bargain price.

I found these, like many of JJill's items, were generously sized. I recommend ordering your usual size. I returned these in white because the fabric was somewhat thin. Probably okay in other colors. I find that to be a common issue with white slacks/pants, skirts, etc.