Regional Statistics
Population in Ostrołęcki County 2025
In 2024, Ostrołęcki county ranked 138 of 380 Polish counties. Population shrank by 1,257 residents -1.42% between 2019-2024, at 87,397.
Among 339 declining counties, ranked in top 20% for steepest loss. Within Masovian voivodeship, ranked 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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Updated 52 days ago
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