<p>The diurnal shifts in population distribution increase uncertainty in healthcare demand patterns, posing a substantial challenge to the traditional principles of healthcare facility allocation. This has generated a substantial demand near workplaces. In response, this paper introduces the worktime population. It combines residents and workers with convenient healthcare access near workplaces, offering a comprehensive measure of healthcare demand. Using Beijing as a case, we explore the unique distributions and scales of healthcare demands, considering both residential and worktime populations. Through meticulous analysis, we evaluate healthcare accessibility for these groups and compare their spatiotemporal variations. Our findings highlight significant statistical and spatial disparities in healthcare demand and accessibility between worktime and residential populations. Overall, healthcare demand from worktime populations surpasses that of residential populations, while accessibility is lower for worktime populations. Traditional accessibility metrics often neglect commuter demands, especially in business and technical districts. Incorporating working-hour constraints further diminishes the accessibility advantage of city centers. These insights facilitate more precise, strategic healthcare facility allocation, assisting policymakers and urban planners enhancing equitable access and mitigating spatial inequities.</p>