Significance. Current demographic trends in Russia, associated with the second demographic transition (population ageing, declining birth rates, and changes in the age structure of society), lead to an increasing share of elderly citizens, greater pressure on the healthcare and social protection systems, and a shift in the structure of healthcare expenditures. According to Rosstat forecasts, by 2046 the proportion of the population above working age will reach 26.9%, necessitating a revision of approaches to healthcare organization and financing. Purpose. To assess actual and projected healthcare utilization and its financing in selected Russian regions by medical service profile and population sex–age groups. Materials and methods. The study is based on aggregated data from Territorial Funds of Mandatory Health Insurance (MHI) and Rosstat for 2023–2046. Methods of statistical analysis, calculation of relative and average indicators, and data visualization in Microsoft Excel were used. Special formulas were applied to assess healthcare utilization and financing, considering the number of visits, service costs, and population size by sex and age. Projections were built on age-specific utilization and cost coefficients extrapolated to the projected sex–age structure. Results. Analysis showed that outpatient care predominates in all studied regions (89.9–95.1% of visits), while inpatient care accounts for the largest share of costs (43–75%). Women account for about 60% of visits and financing. The costliest age groups are newborns, school-age children, women of reproductive age, and the elderly (65+ years). In the structure of visits by disease class, the leading causes are “Factors influencing health status”, diseases of the respiratory system, digestive system, and circulatory system. By 2035, a decrease in the total number of visits is projected, especially among the working-age population and children, with a simultaneous increase among the elderly. Healthcare costs are expected to rise due to the growing share of elderly patients and cardiovascular diseases. Discussion. Common trends across all regions include the predominance of inpatient care, gender dominance of women in visits and financing, and rising costs for the elderly. Regional differences in visit and cost structures are noted, as well as the impact of the COVID-19 pandemic on the nosological structure of expenditures. The necessity of considering sex–age structure in planning healthcare volumes and financing is substantiated. It is proposed to introduce a special coefficient for more accurate distribution of MHI funds, considering the share of the elderly population. Conclusions. Population ageing and changes in disease structure require adaptation of the healthcare system: priority is given to serving the elderly and patients with chronic diseases. An increase in healthcare costs is forecasted, despite a decrease in outpatient visits. There is an urgent need to revise MHI financing mechanisms, considering regional and demographic specifics.