Fasteners, and related methods, for securing deck boards to a support joist are disclosed. In one embodiment, the fastener comprises a base portion and a cap portion on the base portion. In some embodiments, the base portion includes an opening formed therethrough for receiving a securing device, and legs extending from an upper surface of the base portion and between edges of adjacent deck boards to define a spacing between the adjacent deck boards. The cap portion can include an opening for receiving the securing device therethrough to secure the fastener to the support joist. In addition, the cap portion may include legs extending around the base portion and comprising teeth extending therefrom that bite into grooves formed in the edges of the adjacent deck boards when the securing device secures the fastener to the support joist, thereby securing the deck boards to the support joist.