A latch assembly for a surgical instrument, a handle assembly of a surgical instrument including the latch assembly, and a surgical instrument including the latch assembly are provided. The latch assembly includes a lever having a distal engagement section, an intermediate section, and a proximal manipulatable section. The distal engagement section of the lever includes a base and an engagement tooth depending from the base. The engagement tooth is configured to releasably engage first and second components of a surgical instrument with one another and defines a first surface having a concave portion defining a varied radius of curvature.