I ordered an XL for myself.  I am a fairly large dude at 6'3", 250, built like a linebacker, and it fit perfectly.  Some larges may fit similar to how this fit me, but then again, some larges are too small for me.  This was perfect, so it may be between an XL and a L, but I would consider it roughly true to size.  The material is pretty thin, so don't expect this to be a sweater worn for warmth in particular although it would still be better than a T shirt.  I mean, who wears clothing for warmth anymore to begin with?  Anyhow, it's a good-looking sweater although I am unsure of the quality, and I mean that I am unsure, not that it's necessarily bad.  I'm not used to acrylic is all.