Future Estimates of Public Long-Term Care Insurance Premiums in Japan and Their Considerations

Abstract In the context of a globally aging population, nursing care coverage has become a critical issue in insurance research. Japan, where population aging is advancing ahead of global trends, may serve as a reference for many other countries. The country’s public long-term care insurance system, introduced over two decades ago, is administered by 1,571 municipalities (as of 2020), representing a more localized governance structure compared to the 47 prefectures. Half of the system’s financial resources derive from long-term care insurance premiums, which vary across municipalities. Accurate projections of these premiums are essential for informing policies related to social security financing and public fiscal burdens. However, current estimates lack precision. This study projects the long-term care certification rate and insurance premiums at the municipal level for the next 20 years and analyzes regional disparities. Results indicate that nationwide premiums nationwide are expected to increase by 1.5–1.6 times over two decades, with disparities widening between municipalities. By 2040, half of the 20 municipalities with the highest premiums are projected to be in Osaka Prefecture, while substantial increases are also anticipated in commuter areas surrounding Tokyo. These findings underscore the need for targeted policy interventions to mitigate regional inequalities and ensure the financial sustainability of the long-term care system.