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County ProfileMO

Washington County

Population: 23,514 · 10 ZIP codes

Demographics

Source: U.S. Census Bureau (ACS/Decennial). Estimates vary by year.

People
Total population
23,514
People
Median age
40.7
Housing
Total households
8,920
Income
Median household income
$56,043
Housing
Total housing units
10,734
Employment
Employment rate
49.8%
Education
Bachelor’s degree or higher
11.7%
Healthcare
Insured population
89.6%
County details
Local time 04:22:08(CT)
NameWashington
Total ZIP codes10total
ZIP codes (by type)
9 Standard1 PO Box
Area code573, 636
TimezoneCentral Time (CT)
Coordinates37.9426107, -90.8970179
Land area759.9 sq miles(1,968 km²)

Map of Washington county, Missouri with ZIP codes

Map of Washington County, Missouri and ZIP codes

Cities and Communities in Washington County

Compare the largest cities in Washington County by population, median income, and growth. Use the table below to analyze key demographic shifts across the region.

CityPopulation
Median incomeHousehold
ZIP codes
Cadet4,1691ZIPs
Potosi2,538$39,8461ZIPs
Richwoods1,0941ZIPs
Blackwell9351ZIPs
Belgrade9341ZIPs
Irondale368$37,3681ZIPs
Fletcher2671ZIPs
Mineral Point231$41,3941ZIPs
Caledonia131$60,4171ZIPs
Tiff1191ZIPs

Data unavailable or suppressed by the U.S. Census Bureau for areas with small sample sizes to protect individual privacy.

ZIP Codes in Washington County

Review the most populated postal areas across Washington County. Use the ranking below to compare resident density and demographic scales between the county's major zones.

ZIPCity
Median incomeHousehold
Population (ZIP)
63664Potosi$61,2168,333
63630Cadet$52,4824,169
63660Mineral Point$51,4103,699
63648Irondale$51,7651,348
63071Richwoods$44,8531,094
63626Blackwell$82,599935
63622Belgrade$31,750934
63631Caledonia$74,211754
63030Fletcher$91,042267
63674Tiff119

Data Sources & Citations

The geographic and demographic information presented on this site is compiled from publicly available, authoritative sources, including:

  • United States Census BureauDemographic, population, housing, and socioeconomic data sourced from Census Bureau datasets, including the Decennial Census and the American Community Survey (ACS).Census Data
  • United States Postal Service (USPS)ZIP code classifications, delivery types, and postal designations used for reference purposes. USPS ZIP codes are intended for mail delivery and may not always align exactly with Census geographic boundaries.USPS