Every company has different sizing. These are bigger in the hip, or conversely, smaller in the waistline. I think in a way they are true to size. The other two companies which are my favorites, have the waistline associated with a smaller hip size. I sadly did go up a size and will keep to my regime. I am a senior. They do not stay up without pulling them up sometimes. I really like them. I have bought a second pair. Sometimes my legs feel tired when wearing them. Summer pants. They seem to never need washing .