SIZING: This is a Performance Loose-Fit. If your son or daughter prefers a more snug fit shirt or a compression fit shirt, please order one size down. Youth Sizes: XS(4-5), S(7-8), M(10-12), L(14-16), XL(18-20). Can run a little large. If you typically find yourself in between sizes and you prefer a more snug fit, please consider the smaller size. Shop with confidence and our 100% Satisfaction Guarantee.