A winglet includes a vertical member and a mounting member. The mounting member is configured to facilitate the mounting of the winglet to the tip of a fan blade. The vertical member is configured to extend perpendicularly relative the tip of a fan blade. A cuff extends from the vertical member to substantially cover at least a portion of the interface between the end of a fan blade and the vertical member. Adding winglets to fan blades may improve the aerodynamics of the fan blades, and thereby increase efficiencies of a fan.