Sleep deprivation reduces cognitive performance; however, its effects on prospective memory (remembering to perform intended actions) are unknown. One view suggests that effects of sleep deprivation are limited to tasks associated with prefrontal functioning. An alternative view suggests a global, unspecific effect on human cognition, which should affect a variety of cognitive tasks. We investigated the impact of sleep deprivation (25 hours of sleep deprivation vs. no sleep deprivation) on prospective-memory performance in more resource-demanding and less resource-demanding prospective-memory tasks. Performance was lower after sleep deprivation and with a more resource-demanding prospective-memory task, but these factors did not interact. These results support the view that sleep deprivation affects cognition more globally and demonstrate that sleep deprivation increases failures to carry out intended actions, which may have severe consequences in safety-critical situations.