List of counties in Iowa

See also: List of United States counties and county-equivalents

Counties of Iowa
LO SX OA OB DK CY ET PL KH WN HK WT CE MT FD HW CW WH AM CT FT BM BT FN WR HB PT BV CK PM WD IA SA CH WB HM HA GN BH BC DW DB JK JN LN BE TM MR SR BN GR CR CF MN HR SH AB GT DA PK JP PH IW JH CD CN ST MC LA WS KK MK MA WA MD AD CA PW ML MM AA UN CL LC MO WP JF HN DM LE VB DV AN WE DT RN TA PA FM
Location	State of Iowa
Number	99
Populations	4,029 (Adams) – 430,640 (Polk)
Areas	381 square miles (990 km2) (Dickinson) – 973 square miles (2,520 km2) (Kossuth)
Government	County government
Subdivisions	cities, towns, townships, unincorporated communities, census designated place

There are 99 counties in the U.S. state of Iowa. The first two counties, Des Moines County and Dubuque County, were created in 1834 when Iowa was still part of the Michigan Territory. In preparation for Michigan's statehood, part of Michigan Territory was formed into Wisconsin Territory in 1836. Two years later, the western portion was split off to become Iowa Territory. The south-eastern part of Iowa Territory became Iowa, the 29th state in the union, on 28 December 1846, by which point 44 counties had been created. Counties continued to be created by the state government until 1857, when the last county, Humboldt County, was created. One of the most significant days in Iowa county history was January 15, 1851, on which 49 counties were created.

Map of counties numbered as in the National Atlas of the United States

The Iowa Constitution of 1857, which is still in effect today, states that counties must have an area of at least 432 square miles (1,120 km²), and no county may be reduced below that size by boundary changes. However, exceptions to this rule were granted, as ten counties have areas below this size. (The table below shows land area, but the Constitution deals with total area.) The smallest county (Dickinson) has a land area of 381 sq mi (990 km²), while the largest (Kossuth) has an area 973 sq mi (2,520 km²). Polk County is the most densely populated county at 756/sq mi (291.7/km²), an increase in density from 2000 when it was 657 inhabitants per square mile (254/km²). Polk County contains the state's capital and largest city, Des Moines. In addition Iowa has one of the fewest number of counties whose boundaries are dictated by natural means, the vast majority of which being formed by lines of survey instead, resulting in a large number of "box counties".

County information

The number in the column headed "#" is the one used on the map from the National Atlas of the United States, shown on the left. The Federal Information Processing Standard (FIPS) code, which is used by the United States government to uniquely identify counties, is provided with each entry. The FIPS code for each county links to census data for that county.

County	FIPS code	County seat	#	Established	Formed from	Etymology	Population	Area	Map
Adair County	001	Greenfield	69	January 15, 1851	Cass County	John Adair (1757–1840), sixth governor of Kentucky	7,682	569 sq mi (1,474 km2)
Adams County	003	Corning	81	January 15, 1851	Taylor County	John Adams, second President of the United States (1797–1801)	4,029	424 sq mi (1,098 km2)
Allamakee County	005	Waukon	11	February 20, 1847	Clayton County	Disputed, possibly named for Allan Makee, an early Indian trader and guide for early settlers	14,330	640 sq mi (1,658 km2)
Appanoose County	007	Centerville	96	February 17, 1843	Davis County	Appanoose, Native American chief who headed peace party in the Black Hawk War	12,884	496 sq mi (1,285 km2)
Audubon County	009	Audubon	57	January 15, 1851	Black Hawk County and Cass County	John James Audubon (1785–1851), ornithologist and artist	6,119	443 sq mi (1,147 km2)
Benton County	011	Vinton	51	December 21, 1837	Native American lands and Wisconsin Territory	Thomas Hart Benton, United States Senator (1821–1851)	26,076	716 sq mi (1,854 km2)
Black Hawk County	013	Waterloo	39	February 17, 1843	Delaware County	Black Hawk (1767–1838), chief of Fox and Sac Indians and leader in the Black Hawk War	131,090	567 sq mi (1,469 km2)
Boone County	015	Boone	47	January 13, 1846	Polk County	Nathan Boone (1781–1863), one of the first to survey Iowa	26,306	572 sq mi (1,481 km2)
Bremer County	017	Waverly	30	January 15, 1851	Native American lands and Winnebago County	Fredrika Bremer (1801–1865), Swedish poet and author	24,276	428 sq mi (1,109 km2)
Buchanan County	019	Independence	40	December 21, 1837	Delaware County and Wisconsin Territory	James Buchanan, fifteenth President of the United States (1857–1861)	20,958	571 sq mi (1,479 km2)
Buena Vista County	021	Storm Lake	24	January 15, 1851	Clay County and Sac County	Battle of Buena Vista, a battle during the Mexican-American War	20,260	575 sq mi (1,489 km2)
Butler County	023	Allison	29	January 15, 1851	Black Hawk County and Buchanan County	William Orlando Butler (1791–1880), War of 1812 hero and unsuccessful candidate for Vice President	14,867	580 sq mi (1,502 km2)
Calhoun County	025	Rockwell City	34	January 15, 1851	Fox County (renamed)	John Caldwell Calhoun, Vice President of the United States (1825–1832)	9,670	570 sq mi (1,476 km2)
Carroll County	027	Carroll	45	January 15, 1851	Guthrie County	Charles Carroll (1737–1832), longest lived signatory of the Declaration of Independence	20,816	569 sq mi (1,474 km2)
Cass County	029	Atlantic	68	January 15, 1851	Pottawattamie County	Lewis Cass, United States Senator from Michigan and unsuccessful candidate for President (1848)	13,956	564 sq mi (1,461 km2)
Cedar County	031	Tipton	65	December 21, 1837	Wisconsin Territory	Red Cedar River, river which runs through county	18,499	580 sq mi (1,502 km2)
Cerro Gordo County	033	Mason City	17	January 15, 1851	Floyd County	Battle of Cerro Gordo, battle during the Mexican-American War	44,151	568 sq mi (1,471 km2)
Cherokee County	035	Cherokee	23	January 15, 1851	Crawford County	Cherokee Native American tribe	12,072	577 sq mi (1,494 km2)
Chickasaw County	037	New Hampton	19	January 15, 1851	Fayette County	Chickasaw Native American tribe	12,439	505 sq mi (1,308 km2)
Clarke County	039	Osceola	83	January 13, 1846	Lucas County	James Clarke, third Governor of Iowa Territory (1845–1846)	9,286	431 sq mi (1,116 km2)
Clay County	041	Spencer	14	January 15, 1851	Native American lands	Henry Clay, Jr. (1807–1847), officer in the Mexican-American War	16,667	569 sq mi (1,474 km2)
Clayton County	043	Elkader	21	December 21, 1837	Dubuque County and Wisconsin Territory	John M. Clayton (1796–1856), United States Senator from Delaware	18,129	779 sq mi (2,018 km2)
Clinton County	045	Clinton	66	December 21, 1837	Dubuque County and Wisconsin Territory	DeWitt Clinton (1769–1828), Governor of New York	49,116	695 sq mi (1,800 km2)
Crawford County	047	Denison	44	January 15, 1851	Shelby County	William Harris Crawford (1772–1834), United States Senator from Georgia	17,096	714 sq mi (1,849 km2)
Dallas County	049	Adel	59	January 13, 1846	Polk County	George Mifflin Dallas (1792–1864), eleventh Vice President of the United States	66,135	586 sq mi (1,518 km2)
Davis County	051	Bloomfield	97	February 17, 1843	Van Buren County	Garrett Davis (1801–1872), congressman	8,753	503 sq mi (1,303 km2)
Decatur County	053	Leon	94	January 13, 1846	Appanoose County	Stephen Decatur (1779–1820), naval officer in the War of 1812	8,457	532 sq mi (1,378 km2)
Delaware County	055	Manchester	41	December 21, 1837	Dubuque County and Wisconsin Territory	State of Delaware, home of Iowa statehood advocate U.S. Senator John M. Clayton	17,764	578 sq mi (1,497 km2)
Des Moines County	057	Burlington	89	September 6, 1834	Michigan Territory and Wisconsin Territory	Des Moines River, river that once ran through the county	40,325	416 sq mi (1,077 km2)
Dickinson County	059	Spirit Lake	3	January 15, 1851	Kossuth County	Daniel Stevens Dickinson (1800–1866), United States Senator from New York	16,667	381 sq mi (987 km2)
Dubuque County	061	Dubuque	42	September 6, 1834	Michigan Territory and Wisconsin Territory	Julien Dubuque (1762–1810), first permanent white settler in Iowa	93,653	608 sq mi (1,575 km2)
Emmet County	063	Estherville	4	January 15, 1851	Dickinson County and Kossuth County	Robert Emmet (1778–1803), Irish revolutionary and American republican sympathizer	10,302	396 sq mi (1,026 km2)
Fayette County	065	West Union	20	December 21, 1837	Clayton County and Wisconsin Territory	Marquis de Lafayette (1757–1834), Frenchman who aided colonial forces during the American Revolutionary War	20,880	731 sq mi (1,893 km2)
Floyd County	067	Charles City	18	January 15, 1851	Chickasaw County	Charles Floyd (1782–1804), member of the Lewis and Clark Expedition who died in Iowa	16,303	501 sq mi (1,298 km2)
Franklin County	069	Hampton	28	January 15, 1851	Chickasaw County	Benjamin Franklin (1706–1790), statesman and U.S. founding father	10,680	582 sq mi (1,507 km2)
Fremont County	071	Sidney	90	February 24, 1847	Pottawattamie County	John Charles Fremont (1813–1890), officer in Mexican-American War	7,441	511 sq mi (1,323 km2)
Greene County	073	Jefferson	46	January 15, 1851	Dallas County	Nathanael Greene (1742–1786), American Revolutionary War general	9,336	568 sq mi (1,471 km2)
Grundy County	075	Grundy Center	38	January 15, 1851	Black Hawk County	Felix Grundy (1777–1840), United States Senator	12,453	503 sq mi (1,303 km2)
Guthrie County	077	Guthrie Center	58	July 8, 1851	Jackson County	Edwin B. Guthrie, officer in Mexican-American War	10,954	591 sq mi (1,531 km2)
Hamilton County	079	Webster City	36	December 22, 1856	Webster County	William W. Hamilton, President of the Iowa Senate (1856–1857)	15,673	577 sq mi (1,494 km2)
Hancock County	081	Garner	16	January 15, 1851	Wright County	John Hancock (1737–1793), President of the First Continental Congress	11,341	571 sq mi (1,479 km2)
Hardin County	083	Eldora	37	January 15, 1851	Black Hawk County	John J. Hardin (1810–1847), prominent soldier in the Black Hawk War	17,534	569 sq mi (1,474 km2)
Harrison County	085	Logan	55	January 15, 1851	Pottawattamie County	William Henry Harrison (1773–1841), ninth President of the United States	14,928	697 sq mi (1,805 km2)
Henry County	087	Mount Pleasant	88	December 7, 1836	Wisconsin Territory	Disputed; either Henry Dodge (1782–1867), governor of Wisconsin Territory; or James Dougherty Henry, general in the Black Hawk War	20,145	434 sq mi (1,124 km2)
Howard County	089	Cresco	9	January 15, 1851	Chickasaw County	Tilghman Ashurst Howard (1797–1844), congressman	9,566	473 sq mi (1,225 km2)
Humboldt County	091	Dakota City	26	February 26, 1857	Webster County	Alexander von Humboldt (1769–1859), German scientist	9,815	434 sq mi (1,124 km2)
Ida County	093	Ida Grove	32	January 15, 1851	Cherokee County	Mount Ida in Greece	7,089	432 sq mi (1,119 km2)
Iowa County	095	Marengo	63	February 17, 1843	Washington County	Iowa River, river that flows through the county, and which is itself named for the Ioway Native American tribe	16,355	586 sq mi (1,518 km2)
Jackson County	097	Maquoketa	54	December 21, 1837	Wisconsin Territory	Andrew Jackson (1767–1845), seventh President of the United States	19,848	636 sq mi (1,647 km2)
Jasper County	099	Newton	61	January 13, 1846	Mahaska County	William Jasper (1750–1779), sergeant in the American Revolutionary War	36,842	730 sq mi (1,891 km2)
Jefferson County	101	Fairfield	87	January 21, 1839	Native American lands	Thomas Jefferson (1743–1826), third President of the United States	16,843	435 sq mi (1,127 km2)
Johnson County	103	Iowa City	64	December 21, 1837	Des Moines County, Iowa and Wisconsin Territory	Richard Mentor Johnson (1780–1850), Vice President of the United States 1837-1841	130,882	614 sq mi (1,590 km2)
Jones County	105	Anamosa	53	December 21, 1837	Wisconsin Territory	George Wallace Jones (1804–1896), United States Senator from Iowa	20,638	575 sq mi (1,489 km2)
Keokuk County	107	Sigourney	74	December 21, 1837	Washington County	Keokuk (1767–1848), chief of the Sac Native American tribe	10,511	579 sq mi (1,500 km2)
Kossuth County	109	Algona	5	January 15, 1851	Webster County	Lajos Kossuth (1802–1894), Hungarian revolutionary who was inspired by American democratic ideals	15,543	973 sq mi (2,520 km2)
Lee County	111	Fort Madison and Keokuk	99	December 7, 1836	Des Moines County	William Elliott Lee, businessman from the New York Land Company, which sold the county's first tracts of land	35,862	517 sq mi (1,339 km2)
Linn County	113	Cedar Rapids	52	December 21, 1837	Wisconsin Territory	Lewis Fields Linn (1795–1843), doctor and United States Senator from Missouri	211,226	718 sq mi (1,860 km2)
Louisa County	115	Wapello	76	December 7, 1836	Des Moines County	Disputed; either Louisa Massey, a woman then famous for avenging the death of her brother; or Louisa County, Virginia	11,387	402 sq mi (1,041 km2)
Lucas County	117	Chariton	84	January 13, 1846	Monroe County	Robert Lucas (1781–1853), first Governor of Iowa Territory	8,898	431 sq mi (1,116 km2)
Lyon County	119	Rock Rapids	1	January 15, 1851	Woodbury County, Iowa	Nathaniel Lyon (1818–1861), first Union general to be killed in the American Civil War, (formerly named Buncombe County)	11,581	588 sq mi (1,523 km2)
Madison County	121	Winterset	70	January 13, 1846	Polk County	James Madison (1751–1836), fourth President of the United States	15,679	561 sq mi (1,453 km2)
Mahaska County	123	Oskaloosa	73	February 17, 1843	Fox and Sac Indian lands	Mahaska (1784–1834), chief of the Ioway Native American tribe	22,381	571 sq mi (1,479 km2)
Marion County	125	Knoxville	72	June 10, 1845	Washington County	Francis Marion (1732–1795), general in the American Revolutionary War	33,309	554 sq mi (1,435 km2)
Marshall County	127	Marshalltown	49	January 13, 1846	Jasper County	John Marshall (1755–1835), fourth Chief Justice of the United States Supreme Court	40,648	572 sq mi (1,481 km2)
Mills County	129	Glenwood	79	January 15, 1851	Pottawattamie County	Frederick Mills, major killed during the Battle of Churubusco in the Mexican-American War	15,059	437 sq mi (1,132 km2)
Mitchell County	131	Osage	8	January 15, 1851	Chickasaw County	John Mitchel (1815–1875), Irish revolutionary who for a time operated out of the United States	10,776	469 sq mi (1,215 km2)
Monona County	133	Onawa	43	January 15, 1851	Harrison County	Word of Native American origin that perhaps translates to "peaceful valley"	9,243	693 sq mi (1,795 km2)
Monroe County	135	Albia	85	February 17, 1843	Wapello County	James Monroe (1758–1831), fifth President of the United States	7,970	433 sq mi (1,121 km2)
Montgomery County	137	Red Oak	80	January 15, 1851	Polk County	Richard Montgomery (1738–1775), general in the American Revolutionary War	10,740	424 sq mi (1,098 km2)
Muscatine County	139	Muscatine	77	December 7, 1836	Des Moines County	Muscatine Native American tribe	42,745	439 sq mi (1,137 km2)
O'Brien County	141	Primghar	13	January 15, 1851	Cherokee County	William Smith O'Brien (1803–1864), Irish revolutionary who was inspired by American democratic ideals	14,398	573 sq mi (1,484 km2)
Osceola County	143	Sibley	2	January 15, 1851	Woodbury County	Osceola (1804–1838), Native American leader	6,462	399 sq mi (1,033 km2)
Page County	145	Clarinda	91	February 24, 1847	Pottawattamie County	John Page, officer killed in Battle of Palo Alto in the Mexican-American War	15,932	535 sq mi (1,386 km2)
Palo Alto County	147	Emmetsburg	15	January 15, 1851	Kossuth County	Battle of Palo Alto in the Mexican-American War	9,421	564 sq mi (1,461 km2)
Plymouth County	149	Le Mars	22	January 15, 1851	Woodbury County	Landing place of the Pilgrims who came to America on the Mayflower	24,986	864 sq mi (2,238 km2)
Pocahontas County	151	Pocahontas	25	January 15, 1851	Greene County and Humboldt County	Pocahontas (1595–1618), famous Native American woman	7,310	578 sq mi (1,497 km2)
Polk County	153	Des Moines	60	January 13, 1846	Native American lands	James K. Polk (1795–1849), eleventh President of the United States	430,640	570 sq mi (1,476 km2)
Pottawattamie County	155	Council Bluffs	67	February 24, 1847	Native American lands	Pottawattamie Native American tribe	93,158	954 sq mi (2,471 km2)
Poweshiek County	157	Montezuma	62	February 17, 1843	Mesquakie Indian lands	Poweshiek, chief of the Fox tribe	18,914	585 sq mi (1,515 km2)
Ringgold County	159	Mount Ayr	93	February 24, 1847	Taylor County	Samuel Ringgold (1796–1846), major killed in the Mexican-American War	5,131	538 sq mi (1,393 km2)
Sac County	161	Sac City	33	January 15, 1851	Greene County	Sac Native American tribe	10,350	576 sq mi (1,492 km2)
Scott County	163	Davenport	78	December 21, 1837	Wisconsin Territory	Winfield Scott (1786–1866), U.S. Army General during the War of 1812	165,224	458 sq mi (1,186 km2)
Shelby County	165	Harlan	56	January 15, 1851	Cass County	Isaac Shelby (1750–1826), general in the American Revolutionary War and the War of 1812	12,167	591 sq mi (1,531 km2)
Sioux County	167	Orange City	12	January 15, 1851	Plymouth County	Sioux Native American tribe	33,704	768 sq mi (1,989 km2)
Story County	169	Nevada	48	January 13, 1846	Boone County, Jasper County, and Polk County	Joseph Story (1779–1845), United States Supreme Court justice	89,542	573 sq mi (1,484 km2)
Tama County	171	Toledo	50	February 17, 1843	Benton County and Boone County	Disputed; either Taimah, Fox chief; or Taomah, wife of Poweshiek	17,767	721 sq mi (1,867 km2)
Taylor County	173	Bedford	92	February 24, 1847	Page County	Zachary Taylor (1784–1850), twelfth President of the United States	6,317	534 sq mi (1,383 km2)
Union County	175	Creston	82	January 15, 1851	Clarke County	The union of the states	12,534	424 sq mi (1,098 km2)
Van Buren County	177	Keosauqua	98	December 7, 1836	Des Moines County	Martin Van Buren (1782–1862), eighth President of the United States	7,570	485 sq mi (1,256 km2)
Wapello County	179	Ottumwa	86	February 17, 1843	Native American lands	Wapello, chief of the Fox Native American tribe	35,625	432 sq mi (1,119 km2)
Warren County	181	Indianola	71	January 13, 1846	Polk County	Joseph Warren (1741–1775), General in the American Revolutionary War	46,225	572 sq mi (1,481 km2)
Washington County	183	Washington	75	January 25, 1839	Wisconsin Territory	George Washington (1732–1799), first President of the United States	21,704	569 sq mi (1,474 km2)
Wayne County	185	Corydon	95	January 13, 1846	Appanoose County	Anthony Wayne (1745–1796), General in the American Revolutionary War	6,403	526 sq mi (1,362 km2)
Webster County	187	Fort Dodge	35	January 12, 1853	Risley County and Yell County (defunct counties)	Daniel Webster (1782–1852), U.S. Senator from Massachusetts	38,013	715 sq mi (1,852 km2)
Winnebago County	189	Forest City	6	January 15, 1851	Kossuth County	Winnebago Native American tribe	10,866	400 sq mi (1,036 km2)
Winneshiek County	191	Decorah	10	February 20, 1847	Native American lands	Winneshiek, chief of the Winnebago Native American tribe	21,056	690 sq mi (1,787 km2)
Woodbury County	193	Sioux City	31	January 12, 1853	Polk County	Levi Woodbury (1789–1851), Governor of New Hampshire, (formerly named Wahkaw County)	102,172	873 sq mi (2,261 km2)
Worth County	195	Northwood	7	January 15, 1851	Mitchell County	William Jenkins Worth (1794–1849), officer in the Black Hawk War and the Mexican-American War	7,598	400 sq mi (1,036 km2)
Wright County	197	Clarion	27	January 15, 1851	Webster County and Kossuth County	Silas Wright (1795–1847), Governor of New York, and Joseph Albert Wright (1810–1867), Governor of Indiana, brothers	13,229	581 sq mi (1,505 km2)

Former counties

The following counties no longer exist:

• Bancroft (1851–1855), merged with Kossuth County
• Cook (1836–1837), merged with Muscatine County
• Crocker (1870–1871), merged with Kossuth County
• Risley (1851–1853), formed Webster County
• Yell (1851–1853), formed Webster County

See also

• List of cities in Iowa
• List of townships in Iowa

External links

• Iowa: Individual County Chronologies