Women's Size Chart Women's shirts run true to size.* Size Numeric Size Bust Natural Waist XS 0 32.5 25 2 33.5 26 S 4 34.5 27 6 35.5 28 M 8 36.5 29 10 37.5 30 L 12 39 31.5 14 40.5 33 XL 16 42 34.5 18 43.5 36 Our boyfriend fit provides an extra 2 1/2 inches in the body and 2 1/2 inches in length.