While most prior research has demonstrated the wide-ranging beneficial outcomes of intrinsic motivation, some studies have shown that it may lead to deleterious consequences. These conflicting findings indicate that the question of whether employees' intrinsic motivation helps improve their functioning remains open. Drawing on effort-recovery theory and employing a multilevel daily diary design, we aimed to explore how, when, and why employees' daily intrinsic motivation might impact their functioning. Utilizing a sample of tour guides from China, the results suggested that daily intrinsic motivation simultaneously increased next-day state depletion and task performance via nighttime problem-solving pondering (PSP). Moreover, recovery self-efficacy was found to weaken the positive association between nighttime PSP and next-day state depletion and strengthen the positive association between nighttime PSP and next-day task performance. Our research advances knowledge about the differential effects of employees’ daily intrinsic motivation on their next-day performance and well-being.