Order at least 1 size too big because these will shrink a full size as soon as they are washed! Also, these are NOT heavyweight... medium weight might even be a stretch. Once washed, all the ribbing at the sleeves and waist are folded up and need to be ironed flat. I have premium Ts from Kirkland that have been through nearly 100 washes that feel much heavier in weight and don't need ironing when I pull them from the dryer.