So I ordered these shorts in a 12 and a 14.  I usually wear a 12 in US sizes, sometimes smaller.  These shorts have some stretch to them and the 12s fit perfectly with stretch to spare.  The 14s would not have stayed up.  Ordering from random brands on Amazon, I find that I usually have to size up.  But these are actually true to US sizes!!  They 12s are very comfy and fit very nicely.  I'll probably order another pair in another color.