Regional Statistics
Population in Sejneński County 2026
Sejneński county ranks 380 of 380 Polish counties. Population shrank by 1,480 residents -7.43% between 2019-2024, now at 18,434.
Among 339 declining counties, in the bottom 20% for rate of decline. Within Podlaskie voivodeship, ranks 17 of 17 counties.
Based on 31 years of official GUS statistics for Sejneński county and its 5 municipalities within Podlaskie voivodeship.
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Contact Information for Sejneński
Updated 28 days ago
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