Background <p>The ageing and shortage of healthcare workers represents a major problem in many countries worldwide, including Czechia. This study focuses specifically on nurses in the Czech healthcare system. The aims of the article are to describe the age and geographical structures of nurses and analyse their entry into and exit from the healthcare system, as well as to provide projections aimed at highlighting the potential risks of a shortage of nurses.</p> Methods <p>This retrospective observational study utilised data from the largest Czech health insurance company (the General Health Insurance Company of the Czech Republic (GHIC)), which has concluded contracts with almost all healthcare providers in Czechia, for the period from 31 December 2012 to 30 September 2023. Demographic methods were used to evaluate the age structures and entry and exit patterns, which was followed by the compilation of a “what-if” projection model of nursing capacities up to 2035.</p> Results <p>The analysis revealed a clear ageing trend across all the country’s healthcare segments, as reflected in the increasing proportion of nurses in older age groups and the declining representation of younger age groups. If current entry and exit trends continue, projections for 2035 predict declines in both the full-time equivalent capacity (FTE) and physical capacity (headcounts) of up to 8% compared to the year 2022.</p> Conclusions <p>The study points to the need for targeted planning, improved entry conditions for nursing graduates and support for personnel retention, especially in regions and care sectors most at risks of shortages. It further highlights the importance of implementing policies that ensure the long-term sustainability of the nursing workforce in an ageing healthcare system.</p>