Rock Island County, Illinois
Rock Island County, Illinois, has 141,869 residents (July 2025 estimate). Its county seat is Rock Island. It uses Central Time and covers 427 sq mi (1,107 km²) of land.
- Resident population, July 2025
- 141,869
- Land area
- 427 sq mi (1,107 km²)
- County seat or government
- Rock Island
- Time zone
- Central TimeUTC-06:00 in January; UTC-05:00 in July
- Median household income
- $67,159 ± $1,869
- Median home value
- $150,400 ± $3,354
- Median rent, with utilities
- $889 ± $21
- Homes lived in by their owners
- 69.7% ± 1.2 points
- County type
- County
- Metro or micro area
- Davenport-Moline-Rock Island, IA-IL metro areaCentral county
- Water area
- 23.8 sq mi (61.6 km²)
- State
- Illinois
- County code (FIPS)
- 17161
- Coordinates (central point)
- 41.468421, -90.572125
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 Rock Island County
| Time zone | Local time and UTC offset | Next clock change |
|---|---|---|
| Central TimeAmerica/Chicago | UTC-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
- 6126543,748 people
- 6120136,766 people
- 6124423,308 people
- 6126410,073 people
- 612828,394 people
- 612405,795 people
- 612754,253 people
- 612733,120 people
- 612842,599 people
- 612812,520 people
- 612561,926 people
- 612321,469 people
All 21
21 ZIP Code areas overlap Rock Island 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
Rock Island County government website ↗ is the next stop for county offices, tax, voting, jury and records information. A geographic lookup cannot determine eligibility, tax liability or a court obligation.
Townships in Rock Island County, largest first
- South Moline Township36,127 people
- Moline Township22,570 people
- Hampton Township21,529 people
- South Rock Island Township18,160 people
- Rock Island Township15,831 people
- Blackhawk Township9,430 people
- Coal Valley Township4,433 people
- Bowling Township3,335 people
- Andalusia Township2,318 people
- Coe Township2,023 people
- Edgington Township1,505 people
- Port Byron Township1,303 people
All 18
- Zuma Township808 people
- Rural Township778 people
- Cordova Township764 people
- Drury Township739 people
- Buffalo Prairie Township565 people
- Canoe Creek Township539 people
People counts are American Community Survey 2020–2024 5-year estimates. All townships in Illinois, by county
School districts in Rock Island County, largest first
- Moline-Coal Valley School District 4047,779 people
- Rock Island-Milan School District 4142,349 people
- United Township High School District 3039,552 people
- East Moline School District 3726,678 people
- Sherrard Community Unit School District 2008,704 people
- Mercer County School District 4047,985 people
- Rockridge Community Unit School District 3007,712 people
- Riverdale Community Unit School District 1006,779 people
- Orion Community Unit School District 2235,794 people
- Silvis School District 345,191 people
- Erie Community Unit School District 13,549 people
- Hampton School District 292,233 people
All 13
- Carbon Cliff-Barstow School District 361,581 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.
- Moline, Illinois (city)42,197 people
- Rock Island, Illinois (city)36,151 people
- East Moline, Illinois (city)20,904 people
- Silvis, Illinois (city)7,955 people
- Milan, Illinois (village)5,034 people
- Coal Valley, Illinois (village)4,229 people
- Carbon Cliff, Illinois (village)2,151 people
- Hampton, Illinois (village)1,926 people
- Port Byron, Illinois (village)1,854 people
- Andalusia, Illinois (village)1,021 people
- Rapids City, Illinois (village)980 people
- Coyne Center, Illinois (CDP)904 people
All 24
- Cordova, Illinois (village)666 people
- Reynolds, Illinois (village)584 people
- Rock Island Arsenal, Illinois (CDP)470 people
- Hillsdale, Illinois (village)451 people
- Edgington, Illinois (CDP)390 people
- Oak Grove, Illinois (village)277 people
- Taylor Ridge, Illinois (CDP)276 people
- Campbell's Island, Illinois (CDP)203 people
- Illinois City, Illinois (CDP)73 people
- Joslin, Illinois (CDP)56 people
- Barstow, Illinois (CDP)34 people
- Buffalo Prairie, Illinois (CDP)9 people
Bordering areas, nearest first
Distances are straight lines between map points.
- Scott County, Iowa12 mi north
- Mercer County, Illinois20 mi southwest
- Henry County, Illinois24 mi east
- Muscatine County, Iowa28 mi west
- Clinton County, Iowa30 mi north
- Whiteside County, Illinois39 mi northeast
- Louisa County, Iowa40 mi southwest
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