A multi-suture knotless anchor and related method for securing soft tissue, such as tendons, to bone are described. The suture anchor includes a body, a sleeve, and an outer deformable bone locking structure. The bone locking structure has a first low profile configuration for insertion into the bone, and a second larger profile configuration for engaging the bone when actuated. The bone anchor and methods permit a suture attachment that lies beneath the cortical bone surface and does not require tying of knots in the suture.