May we count your visit with Google Analytics? It uses cookies and sends visit data to Google. You can change this any time under Cookie choices. Privacy

Where am ILOCATED

Williamson County, Illinois

Williamson County, Illinois, has 67,225 residents (July 2025 estimate). Its county seat is Marion. It uses Central Time and covers 420 sq mi (1,088 km²) of land.

ChicagoAurora
Williamson County in Illinois
CarbondaleMarionHerrinCartervilleJohnston City
Williamson County and its neighbors (simplified outlines). Open in OpenStreetMap ↗
Resident population, July 2025
67,225
Land area
420 sq mi (1,088 km²)
County seat or government
Marion
Time zone
Central TimeUTC-06:00 in January; UTC-05:00 in July
Median household income
$65,604 ± $3,466
Median home value
$156,400 ± $5,461
Median rent, with utilities
$930 ± $37
Homes lived in by their owners
70.7% ± 1.7 points
County type
County
Metro or micro area
Marion-Herrin, IL micro areaCentral county
Water area
24.1 sq mi (62.5 km²)
State
Illinois
County code (FIPS)
17199
Coordinates (central point)
37.730353, -88.930018
Open this point in the location finder

These coordinates mark a central point for the area, not a street address. Income, home value, rent and homes lived in by their owners: U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates, ± margin at 90% confidence; checked on October 13, 2026.

Time zones in Williamson County

Time zoneLocal time and UTC offsetNext clock change
Central TimeAmerica/ChicagoUTC-06:00 in January; UTC-05:00 in July. Enable JavaScript for the live clock.Enable JavaScript for upcoming changes.

Near a time-zone line, check where you are with the time-zone finder. Your phone’s setting can differ.

ZIP Code areas, largest first

  1. 6295927,793 people
  2. 6290122,946 people
  3. 6294812,758 people
  4. 6291810,658 people
  5. 6289610,627 people
  6. 629515,342 people
  7. 629024,135 people
  8. 629243,168 people
  9. 629392,958 people
  10. 629222,608 people
  11. 628902,377 people
  12. 629172,303 people
All 22
  1. 629352,178 people
  2. 629582,103 people
  3. 629871,724 people
  4. 629741,536 people
  5. 629331,101 people
  6. 62949702 people
  7. 62915384 people
  8. 62967309 people
  9. 62921233 people
  10. 62841118 people

22 ZIP Code areas overlap Williamson County. People counts are 2020–2024 estimates for each whole ZIP area. Mailing ZIPs can differ; check an address with USPS ZIP Code Lookup.

Official county information

We don’t have a website for this county yet. The US government’s local-office directory ↗ lists its offices. A geographic lookup cannot determine eligibility, tax liability or a court obligation.

Precincts in Williamson County, largest first

  1. Herrin Precinct14,121 people
  2. East Marion Precinct11,608 people
  3. West Marion Precinct10,993 people
  4. Carterville Precinct9,772 people
  5. Blairsville Precinct6,200 people
  6. Lake Creek Precinct3,965 people
  7. Southern Precinct3,841 people
  8. Creal Springs Precinct2,078 people
  9. Crab Orchard Precinct1,592 people
  10. Stonefort Precinct1,432 people
  11. Grassy Precinct638 people
  12. Corinth Precinct636 people

People counts are American Community Survey 2020–2024 5-year estimates. All precincts in Illinois, by county

School districts in Williamson County, largest first

  1. Carbondale Community High School District 16532,685 people
  2. Marion Community Unit School District 228,215 people
  3. Herrin Community Unit School District 416,304 people
  4. Carterville Community Unit School District 511,683 people
  5. Frankfort Community Unit School District 16810,560 people
  6. Vienna High School District 1339,821 people
  7. Johnston City Community Unit School District 17,168 people
  8. Zeigler-Royalton Community Unit School District 1883,917 people
  9. Carrier Mills-Stonefort Community Unit School District3,121 people
  10. Crab Orchard Community Unit School District 32,633 people
  11. Giant City Community Consolidated School District 1302,384 people
  12. Galatia Community Unit School District 12,322 people
All 13
  1. New Simpson Hill Consolidated District 322,037 people

Districts with land in the county; a district can cross county lines. People counts are American Community Survey 2020–2024 5-year estimates. A district boundary doesn’t decide which school a student attends.

Cities, towns and communities, largest first

These areas overlap the mapped boundary; an overlap does not mean that every address belongs to both.

  1. Carbondale, Illinois (city)22,158 people
  2. Marion, Illinois (city)16,836 people
  3. Herrin, Illinois (city)12,226 people
  4. Carterville, Illinois (city)5,818 people
  5. Johnston City, Illinois (city)3,327 people
  6. Crainville, Illinois (village)1,641 people
  7. Cambria, Illinois (village)1,300 people
  8. Energy, Illinois (village)1,050 people
  9. Hurst, Illinois (city)700 people
  10. Pittsburg, Illinois (village)682 people
  11. Stonefort, Illinois (village)422 people
  12. Crab Orchard, Illinois (CDP)394 people
All 19
  1. Bush, Illinois (village)354 people
  2. Creal Springs, Illinois (city)324 people
  3. Whiteash, Illinois (CDP)301 people
  4. Spillertown, Illinois (village)246 people
  5. Blairsville, Illinois (CDP)231 people
  6. Colp, Illinois (village)223 people
  7. Freeman Spur, Illinois (village)149 people

Bordering areas, nearest first

Distances are straight lines between map points.

  1. Franklin County, Illinois18 mi north
  2. Johnson County, Illinois19 mi south
  3. Saline County, Illinois21 mi east
  4. Union County, Illinois24 mi southwest
  5. Jackson County, Illinois25 mi west

Before using this answer on a form

Use a precise point for address-level questions. A device accuracy circle can cross a boundary; confirm tax, voting or jury details with the responsible office.

Find the county where you are now, check its ZIP area, or check the time zone where you are.

See this county on Census.gov ↗

Areas that only touch the edge

These areas meet the boundary only along a sliver. Most addresses here are not in them; for an address near the line, check with the county.