Rock Island County, Illinois
Rock Island County: County in Illinois, United States
About
Rock Island County is a county located in the U.S. state of Illinois. As of the 2010 census, the population was 147,546 and a population density of 126 people per km². After 10 years in 2020 county had an estimated population of 140,907 inhabitants. Its county seat is Rock Island. The county was created 194 years ago in 1830.
Quick Facts about Rock Island County
| Population : | 140,907 (2020) |
| Country : | United States of America |
| State : | Illinois (United States) |
| Different from : | Rock County, Rock County, Rock County |
| Area : | 1168 km2 |
| Water as percent of area : | 5.2% |
| Land as percent of area : | 94.8% |
| Named for : | Rock Island Arsenal |
| Altitude : | 587 feet / 179 meters |
| Capital : | Rock Island |
| Establishment : | January 01, 1831 |
| Time Zone : | America/Chicago |
| Local time : | 11:45:42 (22nd February 2025) |
| Density : | 121 Pop. per km² as of 2020 |
| Population growth : | -4.71% (2010-2020) |
Geography
Rock Island County is located at 41°28'2"N 90°34'3"W (41.4673300, -90.5674300). It has 4 neighbors: Clinton County, Muscatine County, Henry County and Mercer County.
Rock Island County map
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The largest city of Rock Island County is Moline with a population of 41,065. Other cities include, Rock Island population 36,870, East Moline population 20,473, Silvis population 7,473 and Coal Valley population 3,719. See all Rock Island County cities & populated places.
Rock Island County Populated Places
Cities, towns, neighborhoods & other populated places in Rock Island County.
| City Name | Population | Title |
|---|---|---|
| Moline | 41,065 | The largest city in Rock Island County, Illinois. |
| Rock Island | 36,870 | City in Illinois |
| East Moline | 20,473 | City in Rock Island County, Illinois, United States |
| Silvis | 7,473 | City in Rock Island County, Illinois, United States |
| Coal Valley | 3,719 | City in Illinois, United States of America |
| Carbon Cliff | 1,932 | City in Illinois, United States of America |
| Hampton | 1,738 | Human settlement in Rock Island County, Illinois, United States of America |
| Port Byron | 1,597 | City in Illinois, United States of America |
| Edgington | 1,442 | Township in Rock Island County, Illinois |
| Andalusia | 1,088 | Human settlement in Illinois, United States of America |
| Rapids City | 962 | Human settlement in Rock Island County, Illinois, United States of America |
| Buffalo Prairie | 796 | Township in Rock Island County, Illinois |
| Cordova | 640 | Village in the United States |
| Reynolds | 508 | Village in Illinois, USA |
| Hillsdale | 502 | Village in Illinois |
- Official Website
Official website of Rock Island County
Rock Island County has 4 neighbours.
- Clinton County county in Iowa, United States of America
- Muscatine County county in Iowa, United States
- Henry County county in Illinois, United States
- Mercer County county in Illinois, United States
- Rock Island
Demographics
According to census records, the population of Rock Island County decreased by 4.71% in 10 years.
| Year | Population | % Change | Method |
| 2010 | 147,546 | - | census |
| 2011 | 147,457 | -0.06% | estimation process |
| 2012 | 147,672 | 0.15% | estimation process |
| 2013 | 147,650 | -0.01% | estimation process |
| 2014 | 147,035 | -0.42% | estimation process |
| 2015 | 146,094 | -0.64% | estimation process |
| 2016 | 144,943 | -0.79% | estimation process |
| 2017 | 143,828 | -0.78% | estimation process |
| 2018 | 142,621 | -0.85% | estimation process |
| 2019 | 141,879 | -0.52% | estimation process |
| 2020 | 140,907 | -0.69% | estimation process |
Illinois Other Counties (more counties)
| County Name | Population | Title |
|---|---|---|
| Cook County | 5,108,284 | County in Illinois, United States |
| Chicago | 2,677,643 | The third most populous city in the United States and the center of the Chicago metropolitan area. |
| DuPage County | 917,481 | County in Illinois, United States |
| Lake County | 693,593 | County in Oregon, United States |
| Will County | 688,726 | County in Illinois, United States |
| Kane County | 531,010 | County in southern Utah, United States |
| McHenry County | 305,888 | County in Illinois, United States |
| Winnebago County | 281,295 | County in Illinois, United States |
| Madison County | 262,635 | County in Montana, United States |
| Saint Clair County | 258,046 | The County of St. |
| Champaign County | 209,192 | County in Illinois, United States |
| Aurora | 196,383 | The second most populous city in Illinois. |
| Sangamon County | 193,882 | County in Illinois, United States |
| Peoria County | 177,652 | County in Illinois, United States of America |
| McLean County | 171,256 | County in North Dakota, United States |
| Naperville | 147,986 | The second most populous city in Illinois. |
