I ordered the 18 in white, love them! So comfortable, yet not sloppy. They have a nice dressy casual look and fit smoothly under my summer tops. The pull-on style makes them as comfortable as yoga pants. The white isn't see/through that I can tell, but I would say maybe no to printed or patterned undergarments just in case. I just ordered another pair in black, love the cropped style for summer and that they aren't tight to the calf, the little bit of flare makes them a bit more presentable and not looking like leggings