Went by the "apparel fit guide" and ordered L (I am size 14) and it fits like 12 - definitely would NOT fit 16 (the guide says 14-16 for L). Should have guessed since the shirt seems/looks fitted - still would have not gone for XL so making the shoppers aware of the sizing. Also it is on the short side, altho does not look like such on the photo. I have not washed it yet so can not speak for durability. Otherwise it is nicely soft.