This article examines interregional mortality inequality between Moscow City and the Republic of Tuva through a decomposition of differences in life expectancy at birth. The empirical basis of the study consists of official statistical data for 2023, which were used to construct abridged life tables for the two regions. To assess age-specific contributions to the overall gap, Arriaga’s decomposition method was applied. The calculations show that life expectancy at birth was 76.99 years in Moscow and 66.70 years in the Republic of Tuva; the total gap reached 10.29 years. The results indicate that differences are formed throughout the life course, but the largest contributions are made by the age groups 30—44, 60—74, and 75 years and older. The contribution of childhood ages remains relatively small. The findings demonstrate that mortality in Tuva has a pronounced premature character and is associated with increased risks in working and older population age groups.

life expectancy, mortality, interregional inequality, Arriaga decomposition method, Republic of Tuva, Moscow, age-specific mortality rates, demographic analysis.