Objective Investigate the immediate and residual impacts of sleep extension in tactical athletes. Methods A randomized controlled trial (Sleep extension = EXT vs Control = CON) was conducted on 50 (EXT: 20.12 ± 2.01 years vs CON: 19.76 ± 1.09 years) tactical athletes enrolled in the Reserve Officers' Training Corps (ROTC). Participants wore actigraphs for 15 consecutive nights and completed a cognitive/motor battery after seven habitual sleep nights, after four sleep extension nights, and after the resumption of habitual sleep for four nights. The CON group remained on habitual sleep schedules for the entire study. Results During the intervention, the EXT group significantly increased mean sleep time (1.36 ± 0.71 h, p < 0.001). After sleep extension, there were significant between-group differences on the mean score change since baseline in Psychomotor Vigilance Test (PVT) reaction time (p = 0.026), Trail Making Test (TMT) – B time (p = 0.027), standing broad jump (SBJ) distance (p < 0.001), and motivation levels [to perform the cognitive tasks (p = 0.003) and the SBJ (p = 0.009)]; with the EXT group showing a greater enhancement in performance/motivation. After resuming habitual sleep schedules, significant between-group differences on the mean score change since baseline persisted on SBJ distance (p = 0.001) and motivation to perform the SBJ (p = 0.035), with the EXT showing greater enhancement in performance/motivation. Conclusion Increasing sleep duration in military tactical athletes resulted in immediate performance benefits in psychomotor vigilance, executive functioning, standing broad jump distance, and motivation levels. Benefits on motor performance were evident four days after resumption of habitual sleep schedules. Military tactical athletes aiming to optimize their overall performance should consider the impact of longer sleep durations when feasible.