Population

Residents of Montgomery County, by year (Census estimates as of July 1).

Montgomery County: 539,598 in 2025. Change from 2024: +0.5%.

400,000600,000Jan 2025Montgomery County 539,598
400,000600,000Jan ’25County 539,598
400,000600,00020212022202320242025Montgomery County 539,598
400,000600,00020212022202320242025County 539,598
400,000600,000800,0001971197419771980198319861989199219951998200120042007201020132016201920222025Montgomery County 539,598
400,000600,000800,0001971197419771980198319861989199219951998200120042007201020132016201920222025County 539,598
Montgomery CountyPopulation, 1970 to 2025. Source: U.S. Census Bureau, Population Estimates Program (through FRED, Federal Reserve Bank of St. Louis).

Next update: 2026 figures, expected around May 20, 2027.

20252024Change
Montgomery County539,598536,930+0.5%

Recent updates

About this data

The Census Bureau’s resident population estimates for July 1 of each year. Each new release revises the past decade’s estimates, so earlier figures can change; the decennial census years (2010, 2020) are the benchmarks.

Source: U.S. Census Bureau, Population Estimates Program (through FRED, Federal Reserve Bank of St. Louis). Updated November 3, 2026, yearly. Download the data (CSV).

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