While most people are aware of the importance of sleep for their health, well‐being, and performance, bedtime procrastination is a pervasive phenomenon that can be conceptualized as a case of self‐control failure (Kroese et al., Frontiers in Psychology, 5, 2014, 1). Two daily diary studies (N1 = 185, N2 = 137) investigated beliefs about willpower and stress as interactive predictors of bedtime procrastination. Beliefs about willpower capture whether people think of their willpower as limited resource that gets easily depleted (limited theory) or as something that remains regardless of previous acts of self‐control (non‐limited theory). Results show that after a stressful day, people with a limited versus non‐limited theory procrastinate more on going to bed, while there is no difference in bedtime procrastination on less stressful days. Thus, ironically, limited theorists who should be more concerned with recovering their resources after a stressful day sleep less the following night.