List of Illinois counties.html |
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This is a list of the 102 counties in the state of Illinois. Information on the FIPS county code, county seat, year of establishment, origin, etymology, population, area and map of each county is included in the table below.
Alphabetical list
Note: the links in the FIPS County Code column are to the Census Bureau info page for that county.
| County |
FIPS Code 1 |
County seat 2 |
Established 2 |
Origin |
Etymology34 |
Population 2 |
Area 2 |
Map |
|---|---|---|---|---|---|---|---|---|
| Adams County | 001 | Quincy | 1825 | Pike County | John Quincy Adams (1767-1848), Second President of the United States | 68,277 | 857 sq mi (2,220 km²) |
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| Alexander County | 003 | Cairo | 1819 | state of Missouri | William M. Alexander, a settler and State Representative in the Illinois General Assembly | 9,590 | 236 sq mi (611 km²) |
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| Bond County | 005 | Greenville | 1817 | Crawford County, Edwards County, and Madison County | Shadrach Bond (1773-1832), First Governor of Illinois | 17,633 | 380 sq mi (984 km²) |
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| Boone County | 007 | Belvidere | 1837 | Winnebago County | Daniel Boone (1734-1820), trailblazer of the Wilderness Road in Kentucky | 41,786 | 281 sq mi (728 km²) |
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| Brown County | 009 | Mount Sterling | 1839 | Schuyler County | Jacob Brown (1775-1828), a successful American Revolution army officer responsible for Great Lakes defenses | 6,950 | 306 sq mi (793 km²) |
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| Bureau County | 011 | Princeton | 1837 | Putnam County | Pierre de Bureo, Frenchman, North American fur trader | 35,503 | 869 sq mi (2,251 km²) |
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| Calhoun County | 013 | Hardin | 1825 | Pike County | John C. Calhoun (1782-1850), South Carolina senator and seventh Vice President of the United States | 5,084 | 254 sq mi (658 km²) |
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| Carroll County | 015 | Mount Carroll | 1839 | Jo Daviess | Charles Carroll of Carrollton (1737-1832), signed the Declaration of Independence on behalf of Maryland | 16,674 | 444 sq mi (1,150 km²) |
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| Cass County | 017 | Virginia | 1837 | Morgan County | Lewis Cass (1782-1866), Second governor of Michigan Territory from which Illinois was formed, Fourteenth United States Secretary of War | 13,695 | 376 sq mi (974 km²) |
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| Champaign County | 019 | Urbana | 1833 | Vermilion County | Champaign County, Ohio | 179,669 | 997 sq mi (2,582 km²) |
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| Christian County | 021 | Taylorville | 1839 | Sangamon County | Christian County, Kentucky | 35,372 | 709 sq mi (1,836 km²) |
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| Clark County | 023 | Marshall | 1819 | Crawford County | George Rogers Clark (1752-1818), Highest ranking officer in the Northwest Territory during the American Revolution, in which Illinois was located | 17,008 | 502 sq mi (1,300 km²) |
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| Clay County | 025 | Louisville | 1824 | Wayne, Lawrence, Fayette, and Crawford County | Henry Clay (1777-1852), Kentucky legislator who negotiated the Missouri Compromise | 14,560 | 469 sq mi (1,215 km²) |
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| Clinton County | 027 | Carlyle | 1824 | Washington, Bond, and Fayette County | DeWitt Clinton (1769-1828), Governor of New York, responsible for the construction of the Erie Canal | 35,535 | 474 sq mi (1,228 km²) |
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| Coles County | 029 | Charleston | 1830 | Clark and Edgar County | Edward Coles (1786-1868) Second Governor of Illinois, responsible for the abolition of slavery in Illinois | 53,196 | 508 sq mi (1,316 km²) |
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| Cook County | 031 | Chicago | 1831 | Putnam County | Daniel Pope Cook (1794-1827), politician and first Attorney General of Illinois | 5,376,741 | 946 sq mi (2,450 km²) |
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| Crawford County | 033 | Robinson | 1816 | Edwards County | William H. Crawford (1772-1834) Ninth United States Secretary of War, seventh Secretary of the Treasury | 20,452 | 444 sq mi (1,150 km²) |
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| Cumberland County | 035 | Toledo | 1843 | Coles County | Disputed: Cumberland Road, which entered the county; Cumberland, Maryland; or Cumberland River in Kentucky | 11,253 | 346 sq mi (896 km²) |
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| De Witt County | 039 | Clinton | 1839 | Macon and McLean County | DeWitt Clinton (1769-1828), Governor of New York, responsible for the construction of the Erie Canal | 16,798 | 398 sq mi (1,031 km²) |
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| DeKalb County | 037 | Sycamore | 1837 | Kane County | Johann de Kalb (1721-1780), German soldier in the Continental Army who fought alongside Gilbert du Motier, marquis de Lafayette | 88,969 | 634 sq mi (1,642 km²) |
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| Douglas County | 041 | Tuscola | 1859 | Coles County | Stephen A. Douglas (1813-1861), prominent Illinois Democrat who engaged in debates with Abraham Lincoln | 19,922 | 417 sq mi (1,080 km²) |
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| DuPage County | 043 | Wheaton | 1839 | Cook County | DuPage River | 904,161 | 334 sq mi (865 km²) |
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| Edgar County | 045 | Paris | 1823 | Clark County | John Edgar (circa 1750-1832), Illinois delegate to the Northwest Territory legislature; at time, wealthiest man in Illinois | 19,704 | 624 sq mi (1,616 km²) |
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| Edwards County | 047 | Albion | 1814 | Gallatin County and Madison County | Ninian Edwards (1775-1833), third Governor of the State of Illinois and only Governor of Illinois Territory | 6,971 | 222 sq mi (575 km²) |
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| Effingham County | 049 | Effingham | 1831 | Fayette and Crawford County | Lord Edward Effingham, military officer who resigned from the British Army to avoid fighting the American colonies | 34,264 | 479 sq mi (1,241 km²) |
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| Fayette County | 051 | Vandalia | 1821 | Bond, Wayne, Clark, Jefferson, and Crawford County | Marquis de la Fayette (1757-1834), a French military officer who was a key factor in the American and French Revolutions. | 21,802 | 716 sq mi (1,854 km²) |
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| Ford County | 053 | Paxton | 1859 | Kankakee County | Thomas Ford (1800-1850), Eighth Governor of Illinois; served during the Illinois Mormon War | 14,241 | 486 sq mi (1,259 km²) |
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| Franklin County | 055 | Benton | 1818 | White County and Gallatin County | Benjamin Franklin (1706-1790), prolific writer, inventor, and politician; key factor in the American Revolution | 39,018 | 412 sq mi (1,067 km²) |
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| Fulton County | 057 | Lewistown | 1823 | Pike County | Robert Fulton (1765-1815), inventor of the steamboat | 38,250 | 866 sq mi (2,243 km²) |
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| Gallatin County | 059 | Shawneetown | 1812 | Randolph County | Albert Gallatin (1761-1849), Fourth and longest-serving United States Secretary of the Treasury | 6,445 | 324 sq mi (839 km²) |
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| Greene County | 061 | Carrollton | 1821 | Madison County | Nathanael Greene (1742-1786), Major general in the Continental Army | 14,761 | 543 sq mi (1,406 km²) |
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| Grundy County | 063 | Morris | 1841 | LaSalle County | Felix Grundy (1777-1840), Tennessean senator that served as the thirteenth United States Attorney General | 37,535 | 420 sq mi (1,088 km²) |
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| Hamilton County | 065 | McLeansboro | 1821 | White County | Alexander Hamilton (1755-1804), First United States Secretary of the Treasury | 8,621 | 435 sq mi (1,127 km²) |
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| Hancock County | 067 | Carthage | 1825 | Adams County | John Hancock (1737-1793), first governor of the Massachusetts colony and president of the Second Continental Congress | 20,121 | 795 sq mi (2,059 km²) |
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| Hardin County | 069 | Elizabethtown | 1839 | Pope County | Hardin County, Kentucky | 4,800 | 178 sq mi (461 km²) |
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| Henderson County | 071 | Oquawka | 1841 | Warren County | Henderson County, Kentucky | 8,213 | 379 sq mi (982 km²) |
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| Henry County | 073 | Cambridge | 1825 | Adams County | Patrick Henry | 51,020 | 823 sq mi (2,132 km²) |
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| Iroquois County | 075 | Watseka | 1833 | Vermilion County | Iroquois Native Americans | 31,334 | 1,116 sq mi (2,890 km²) |
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| Jackson County | 077 | Murphysboro | 1816 | Randolph County and Johnson County | Andrew Jackson | 59,612 | 588 sq mi (1,523 km²) |
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| Jasper County | 079 | Newton | 1831 | Clay and Crawford County | William Jasper | 10,117 | 494 sq mi (1,279 km²) |
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| Jefferson County | 081 | Mount Vernon | 1819 | Edwards and White County | Thomas Jefferson | 40,045 | 571 sq mi (1,479 km²) |
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| Jersey County | 083 | Jerseyville | 1839 | Greene County | New Jersey | 21,668 | 369 sq mi (956 km²) |
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| Jo Daviess County | 085 | Galena | 1827 | Henry, Mercer, and Putnam County | Joseph Hamilton Daviess | 22,289 | 601 sq mi (1,557 km²) |
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| Johnson County | 087 | Vienna | 1812 | Randolph County | Richard Mentor Johnson | 12,878 | 346 sq mi (896 km²) |
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| Kane County | 089 | Geneva | 1836 | Cook County | Elias Kane | 404,119 | 521 sq mi (1,349 km²) |
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| Kankakee County | 091 | Kankakee | 1853 | Iroquois and Will County | Kankakee River | 103,833 | 678 sq mi (1,756 km²) |
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| Kendall County | 093 | Yorkville | 1841 | LaSalle and Kane County | Amos Kendall | 54,544 | 321 sq mi (831 km²) |
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| Knox County | 095 | Galesburg | 1825 | original two counties | Gen. Henry Knox | 55,836 | 716 sq mi (1,854 km²) |
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| Lake County | 097 | Waukegan | 1839 | McHenry County | lakes in the county | 644,356 | 448 sq mi (1,160 km²) |
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| LaSalle County | 099 | Ottawa | 1831 | Putnam County | Sieur de la Salle | 111,509 | 1,135 sq mi (2,940 km²) |
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| Lawrence County | 101 | Lawrenceville | 1821 | Crawford and Edwards County | James Lawrence | 15,452 | 372 sq mi (963 km²) |
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| Lee County | 103 | Dixon | 1839 | Ogle County | Lighthorse Harry Lee | 36,062 | 725 sq mi (1,878 km²) |
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| Livingston County | 105 | Pontiac | 1837 | LaSalle and McLean County | Edward Livingston | 39,678 | 1,044 sq mi (2,704 km²) |
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| Logan County | 107 | Lincoln | 1839 | Sangamon County | John A. Logan | 31,183 | 618 sq mi (1,601 km²) |
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| Macon County | 115 | Decatur | 1829 | Shelby County | Nathaniel Macon | 114,706 | 581 sq mi (1,505 km²) |
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| Macoupin County | 117 | Carlinville | 1829 | Greene County | Native American word Macoupin | 49,019 | 864 sq mi (2,238 km²) |
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| Madison County | 119 | Edwardsville | 1812 | St. Claire County and Randolph County | James Madison | 258,941 | 725 sq mi (1,878 km²) |
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| Marion County | 121 | Salem | 1823 | Fayette and Jefferson County | Francis Marion | 41,691 | 572 sq mi (1,481 km²) |
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| Marshall County | 123 | Lacon | 1839 | Putnam County | John Marshall | 13,180 | 386 sq mi (1,000 km²) |
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| Mason County | 125 | Havana | 1841 | Tazewell and Menard County | George Mason | 16,038 | 539 sq mi (1,396 km²) |
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| Massac County | 127 | Metropolis | 1843 | Pope and Johnson County | Fort Massac | 15,161 | 239 sq mi (619 km²) |
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| McDonough County | 109 | Macomb | 1826 | Schuyler County | Commodore Thomas McDonough | 32,913 | 589 sq mi (1,526 km²) |
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| McHenry County | 111 | Woodstock | 1836 | Cook County | Gen. William McHenry | 260,077 | 604 sq mi (1,564 km²) |
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| McLean County | 113 | Bloomington | 1830 | Tazewell County | John McLean | 150,433 | 1,184 sq mi (3,067 km²) |
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| Menard County | 129 | Petersburg | 1839 | Sangamon County | Pierre Menard | 12,486 | 314 sq mi (813 km²) |
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| Mercer County | 131 | Aledo | 1825 | Schuyler County | Hugh Mercer | 16,957 | 561 sq mi (1,453 km²) |
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| Monroe County | 133 | Waterloo | 1816 | Randolph County and St. Claire County | James Monroe | 27,619 | 388 sq mi (1,005 km²) |
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| Montgomery County | 135 | Hillsboro | 1821 | Bond and Madison County | Richard Montgomery | 30,652 | 704 sq mi (1,823 km²) |
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| Morgan County | 137 | Jacksonville | 1823 | Sangamon County | Daniel Morgan | 36,616 | 569 sq mi (1,474 km²) |
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| Moultrie County | 139 | Sullivan | 1843 | Shelby and Macon County | William Moultrie | 14,287 | 336 sq mi (870 km²) |
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| Ogle County | 141 | Oregon | 1836 | Jo Daviess | Joseph Ogle | 51,032 | 759 sq mi (1,966 km²) |
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| Peoria County | 143 | Peoria | 1825 | Fulton County | Native American Peoria | 183,433 | 620 sq mi (1,606 km²) |
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| Perry County | 145 | Pinckneyville | 1827 | Randolph and Jackson County | Oliver Hazard Perry | 23,094 | 441 sq mi (1,142 km²) |
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| Piatt County | 147 | Monticello | 1841 | De Witt and Macon County | John Piatt | 16,365 | 440 sq mi (1,140 km²) |
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| Pike County | 149 | Pittsfield | 1821 | Madison, Bond, and Clark County | Zebulon Pike | 17,384 | 830 sq mi (2,150 km²) |
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| Pope County | 151 | Golconda | 1816 | Gallatin and Johnson County | Nathaniel Pope | 4,413 | 371 sq mi (961 km²) |
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| Pulaski County | 153 | Mound City | 1843 | Alexander and Johnson County | Kazimierz Pulaski | 7,348 | 201 sq mi (521 km²) |
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| Putnam County | 155 | Hennepin | 1825 | Peoria County | Israel Putnam | 6,086 | 160 sq mi (414 km²) |
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| Randolph County | 157 | Chester | 1795 | St. Claire County | Edmund Randolph | 33,893 | 578 sq mi (1,497 km²) |
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| Richland County | 159 | Olney | 1841 | Clay and Lawrence County | Richland County Oh. | 16,149 | 360 sq mi (932 km²) |
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| Rock Island County | 161 | Rock Island | 1831 | Jo Daviess County | Rock Island | 149,374 | 427 sq mi (1,106 km²) |
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| Saline County | 165 | Harrisburg | 1847 | Gallatin County | salt springs within the county | 26,733 | 383 sq mi (992 km²) |
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| Sangamon County | 167 | Springfield | 1821 | Madison and Bond County | Sangamon River | 188,951 | 868 sq mi (2,248 km²) |
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| Schuyler County | 169 | Rushville | 1825 | Pike and Fulton County | Philip Schuyler | 7,189 | 437 sq mi (1,132 km²) |
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| Scott County | 171 | Winchester | 1839 | Morgan County | Scott family | 5,537 | 251 sq mi (650 km²) |
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| Shelby County | 173 | Shelbyville | 1827 | Fayette County | Isaac Shelby | 22,893 | 759 sq mi (1,966 km²) |
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| St. Clair County | 163 | Belleville | 1790 | original two counties | Arthur St. Clair | 256,082 | 664 sq mi (1,720 km²) |
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| Stark County | 175 | Toulon | 1839 | Knox and Putnam County | John Stark | 6,332 | 288 sq mi (746 km²) |
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| Stephenson County | 177 | Freeport | 1837 | Jo Daviess and Winnebago County | Benjamin Stephenson | 48,979 | 564 sq mi (1,461 km²) |
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| Tazewell County | 179 | Pekin | 1827 | Sangamon County | Littleton Waller Tazewell | 128,485 | 649 sq mi (1,681 km²) |
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| Union County | 181 | Jonesboro | 1818 | Johnson County | federal union | 18,293 | 416 sq mi (1,077 km²) |
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| Vermilion County | 183 | Danville | 1826 | Clark and Edgar County | Vermilion River | 83,919 | 899 sq mi (2,328 km²) |
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| Wabash County | 185 | Mount Carmel | 1824 | Edwards County | Wabash River | 12,937 | 224 sq mi (580 km²) |
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| Warren County | 187 | Monmouth | 1825 | Schuyler County | Joseph Warren | 18,735 | 543 sq mi (1,406 km²) |
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| Washington County | 189 | Nashville | 1818 | St. Claire County | George Washington | 15,148 | 563 sq mi (1,458 km²) |
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| Wayne County | 191 | Fairfield | 1819 | Knox County | Gen. "Mad" Anthony Wayne | 17,151 | 714 sq mi (1,849 km²) |
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| White County | 193 | Carmi | 1815 | Gallatin County | Isaac White | 15,371 | 495 sq mi (1,282 km²) |
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| Whiteside County | 195 | Morrison | 1836 | Jo Daviess and Henry County | Samuel Whiteside | 60,653 | 685 sq mi (1,774 km²) |
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| Will County | 197 | Joliet | 1836 | Cook and Iroquois County | Conrad Will | 502,266 | 837 sq mi (2,168 km²) |
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| Williamson County | 199 | Marion | 1839 | Franklin County | Hugh Williamson | 61,296 | 424 sq mi (1,098 km²) |
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| Winnebago County | 201 | Rockford | 1836 | Jo Daviess | Winnebago Native Americans | 278,418 | 514 sq mi (1,331 km²) |
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| Woodford County | 203 | Eureka | 1841 | Tazewell and McLean County | William Woodford | 35,469 | 528 sq mi (1,368 km²) |
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