Disclosed herein are sports helmets having modular components. A modular component includes an eyewear adapter that is releasably attachable to the helmet and configured to interface with corresponding eyewear in an orientation that permits a wearer of the helmet to see through the eyewear. The eyewear adapter is configured such that, in use, the eyewear adapter enhances the fit or function of the eyewear relative to the use of the helmet and the eyewear without the eyewear adapter. A modular component includes electronics modules that can be mechanically and electrically coupled to the helmet. A modular component includes other functional modules that affect the aerodynamics of the helmet, the air flow of the helmet, the fit of the helmet, or the look of the helmet.