Regional Statistics
Population in Ostrołęcki County 2026
Ostrołęcki county ranks 138 of 380 Polish counties. Population shrank by 1,257 residents -1.42% between 2019-2024, now at 87,397.
Among 339 declining counties, ranks in top 20% for steepest loss. Within Masovian voivodeship, ranks 16 of 42 counties (9 growing, 33 declining).
Based on 31 years of official GUS statistics for Ostrołęcki county and its 11 municipalities within Masovian voivodeship.
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Contact Information for Ostrołęcki
Updated 28 days ago
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