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 40% for population loss. Within Masovian voivodeship, ranks 16 of 42 counties.
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 77 days ago
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