Editing List of counties in Ohio

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{{Use mdy dates|date=April 2024}}
[[File:Ohio Counties Labeled White.svg|thumb|right|300px|Counties of Ohio]]

There are 88 [[County (United States)|counties]] in the [[U.S. state]] of [[Ohio]]. Nine of them existed at the time of the [[Ohio Constitutional Convention (1802)|Ohio Constitutional Convention]] in 1802.<ref name="Laning">{{cite journal|last1=Laning|first1=J.F.|author-link=J. Ford Laning|year=1896|title=The Evolution of Ohio Counties|journal=[[Ohio Archaeological and Historical Publications]]|volume=V|pages=326–350|url=http://publications.ohiohistory.org/ohj/browse/volumeresult.php?page=2&ipp=20&vol=5|url-status=dead|archive-url=https://web.archive.org/web/20151121000518/http://publications.ohiohistory.org/ohj/browse/volumeresult.php?page=2&ipp=20&vol=5|archive-date=November 21, 2015}}. Other editions available at {{ISBN|1249686741}} and [https://books.google.com/books?id=2mIUAAAAYAAJ&dq=The+Evolution+of+Ohio+Counties&pg=PA326 Google Books]</ref> A tenth county, [[Wayne County, Michigan|Wayne]], was established on August 15, 1796, and encompassed roughly the present state of [[Michigan]].<ref name="OH Statehood">{{cite book |last=Lawyer |first=James Patterson |url=https://books.google.com/books?id=cHgt2eYYXqwC&q=History+of+Ohio:+to+the+Present+Time&pg=PA6 |title=History of Ohio: From the Glacial Period to the Present Time |publisher=Press of F. J. Heer |year=1905 |page=381 |access-date=August 18, 2007}} Other editions available at {{ISBN|9781279183281}}</ref> During the Convention, the county was opposed to statehood, and was not only left out of the Convention, but dissolved; the current [[Wayne County, Ohio|Wayne County]] is in northeastern Ohio, considerably distant from the area that was the original Wayne County.<ref name="Laning"/>

The [[Ohio Constitution]] allows counties to set up a [[Municipal charter|charter]] government as many [[city#United States|cities]] and [[Village (United States)#Ohio|village]]s do,<ref name="charter">{{cite book |title= The Ohio State Constitution A Reference Guide|last1= Steinglass |first1= Steven |last2=Scarselli|first2=Gino|year= 2004|publisher= Praeger Publishers|location= Westport, CT |pages= 272–273 }} (OH county charter). Other editions available: {{ISBN|0313267650}} and [https://books.google.com/books?isbn=0313267650 Google Books]</ref> but only [[Summit County, Ohio|Summit]] and [[Cuyahoga County, Ohio|Cuyahoga]] counties have done so,<ref name="yes">{{cite web |date=November 15, 2011 |title=Ohio Counties |url=http://www.co.summit.oh.us/index.php/links/ohio-counties |url-status=usurped |archive-url=https://web.archive.org/web/20200127094019/http://www.co.summit.oh.us/index.php/links/ohio-counties |archive-date=January 27, 2020 |access-date=February 28, 2013 |publisher=County of Summit}}</ref> the latter having been approved by voters in November 2009.<ref>{{cite web|url=http://www.cleveland.com/politics/index.ssf/2009/11/issue_6_reform_wins_big_and_se.html|title= Issue 6 reform wins big and sets in motion even bigger changes for Cuyahoga County|date= November 4, 2009|publisher= cleveland.com|access-date= January 28, 2010}}</ref> Counties do not possess [[home rule]] powers and can do only what has been expressly authorized by the [[Ohio General Assembly]]. The elected county officials in [[Ohio county government]]s include [[County commission|three commissioners]], a [[Sheriffs in the United States|sheriff]] (the highest law enforcement officer in the county); prosecutor (equivalent of a [[district attorney]] in other states); [[coroner]], engineer, Recorder, [[County auditor|auditor]], [[treasurer]], and [[Court clerk|clerk of courts]].<ref>{{cite web|url=https://www.ohiobar.org/AboutOSBA/People/Pages/StaffDirectory.aspx|title=OSBA - OSBA Staff Directory|website=www.ohiobar.org}}</ref><ref name="ORC Title III">{{cite web|url=http://codes.ohio.gov/orc/3|title=Title 3 - Ohio Revised Code &#124; Ohio Laws}}</ref>

Population figures are based on the 2024 vintage [[United States Census|Census]] population estimates. The population of Ohio was 11,883,304 at that time, an increase of 0.7% from 2020. The average population of Ohio's counties was 135,038; [[Franklin County, Ohio|Franklin County]] was the most populous (1,356,303) and [[Vinton County, Ohio|Vinton County]] was the least (12,545). The average land area is {{convert|464|sqmi|abbr=on}}. The largest county by area is [[Ashtabula County, Ohio|Ashtabula County]] at {{convert|702.44|sqmi|abbr=on}}, and its neighbor, [[Lake County, Ohio|Lake County]], is the smallest at {{convert|228.21|sqmi|abbr=on}}. The total area of the state is {{convert|40,860.69|sqmi|abbr=on}}.<ref name="cen">{{cite web|url=http://quickfacts.census.gov/qfd/states/39000.html |title=Ohio QuickFacts |publisher=U.S. Census Bureau |access-date=February 27, 2013 |url-status=dead |archive-url=https://web.archive.org/web/20130303055638/http://quickfacts.census.gov/qfd/states/39000.html |archive-date=March 3, 2013 }}</ref><ref name="2000pop">{{cite web|url=https://www.census.gov/popest/states/states.html |archive-url=https://web.archive.org/web/20090322152314/http://www.census.gov/popest/states/states.html |url-status=dead |archive-date=March 22, 2009 |title=Population Estimates |publisher=U.S. Census Bureau |date=December 2009 |access-date=February 27, 2013 }}</ref>

==List of counties==
{{Countytabletop
|fips_ref=<ref name="FIPS"/>
|region_seat_title=County Seat
|region_seat_ref=<ref name=NACo>{{cite web |url=http://www.naco.org/Template.cfm?Section=Find_a_County&Template=/cffiles/counties/state.cfm&statecode=oh |title=NACo - Find a County |access-date=July 22, 2007 |archive-url=https://web.archive.org/web/20070413041811/http://www.naco.org/Template.cfm?Section=Find_a_County&Template=%2Fcffiles%2Fcounties%2Fstate.cfm&statecode=oh |archive-date=April 13, 2007 |url-status=dead }}</ref>
|region_seat_width=
|data2_title={{abbr|Est.|Established}}
|data2_ref=<ref name=federal>{{cite web|url=https://www.sos.state.oh.us/sos/upload/publications/election/fedroster2009/HistoricalAppendix.pdf|title=Federal Roster: Counties of Ohio, Derivation of Name and Date of Erection|access-date=July 21, 2013|url-status=bot: unknown|archive-url=https://web.archive.org/web/20130712062648/https://www.sos.state.oh.us/sos/upload/publications/election/fedroster2009/HistoricalAppendix.pdf|archive-date=July 12, 2013}}</ref>
|data2_width=
|data3_ref=<ref name="source">{{cite book |title= Historical Collections of Ohio|last= Howe |first= Henry |year= 1891|publisher= Henry Howe and Son|location= Columbus, OH|volume= 2}} (OH county source). Other editions available: {{ISBN|1425565735}} and [https://books.google.com/books?id=wXEOAAAAIAAJ Google Books]</ref>
|data4_ref=<ref name=federal/><ref name="source"/>
|population_ref=<ref name="FIPS"/><ref name=NACo/><ref>{{cite web |title=QuickFacts: Ohio |url=https://www.census.gov/quickfacts/fact/table/OH/PST045223 |website=United States Census Bureau |access-date=18 March 2025}}</ref>
|population_year=2024
|area_ref=<ref name=NACo/>
}}
{{Countyrow|Name=Adams|N=39|Num=001|Seat=West Union|Data1={{dts|1797|7|10|abbr=on}}|Data2=Hamilton County|Data3=[[John Adams]] (1735–1826), [[President of the United States]] when the county was organized|Population=27671 |Area=583.91|Size=100px}}
{{Countyrow|Name=Allen|N=39|Num=003|Seat=Lima|Data1={{dts|1820|3|1|abbr=on}}|Data2=Shelby County|Data3=[[John Allen (soldier)|John Allen]] (1771/2-1813), a [[War of 1812]] colonel<ref>[[:Image:Allen-naming-resolution.jpg|Resolution of 111th Ohio General Assembly designating John Allen as the person for which Allen County was named]].</ref>|Population=100866|Area=404.43|Size=100px}}
{{Countyrow|Name=Ashland|N=39|Num=005|Seat=Ashland|Data1={{dts|1846|2|24|abbr=on}}|Data2=Wayne, Richland, Huron, and Lorain Counties|Data3=[[Ashland (Henry Clay home)|Ashland]], home of U.S. Senator from [[Kentucky]] [[Henry Clay]] |Population=52420 | Area=424.37| Size=100px}}
{{Countyrow|Name=Ashtabula|N=39|Num=007|Seat=Jefferson|Data1={{dts|1807|6|7|abbr=on}}|Data2=Trumbull and Geauga Counties|Data3=[[Ashtabula River]], which means "fish river" in an [[Algonquian languages|Algonquian language]]<ref>[https://www.britannica.com/eb/article-9009848/Ashtabula Ashtabula], [[Encyclopædia Britannica]], 2007.  Accessed November 19, 2007.</ref>|Population=96906|Area=702.44|Size=100px}}
{{Countyrow|Name=Athens|N=39|Num=009|Seat=Athens|Data1={{dts|1805|3|1|abbr=on}}|Data2=Washington County|Data3=[[Athens]] in Greece|Population=63218 |Area=506.76|Size=100px}}
{{Countyrow|Name=Auglaize|N=39|Num=011|Seat=Wapakoneta|Data1={{dts|1848|2|14|abbr=on}}|Data2=Allen, Mercer, Darke, Hardin, Logan, Shelby, and Van Wert Counties|Data3=[[Auglaize River]], which means "fallen timbers river" in the [[Shawnee]] Indian language|Population=45922|Area=401.25|Size=100px}}
{{Countyrow|Name=Belmont|N=39|Num=013|Seat=St. Clairsville|Data1={{dts|1801|9|7|abbr=on}}|Data2=Jefferson and Washington Counties|Data3=French for "beautiful mountain"|Population=64692|Area=537.35|Size=100px}}
{{Countyrow|Name=Brown|N=39|Num=015|Seat=Georgetown|Data1={{dts|1818|3|1|abbr=on}}|Data2=Adams and Clermont Counties|Data3=General [[Jacob Brown (general)|Jacob Brown]] (1775–1828), an officer of the [[War of 1812]]|Population=44292|Area=491.76|Size=100px}}
{{Countyrow|Name=Butler|N=39|Num=017|Seat=Hamilton|Data1={{dts|1803|5|1|abbr=on}}|Data2=Hamilton County|Data3=General [[Richard Butler (general)|Richard Butler]] (1743–1791), killed at the [[St. Clair's Defeat|Battle of the Wabash]]|Population=399542|Area=467.27|Size=100px}}
{{Countyrow|Name=Carroll|N=39|Num=019|Seat=Carrollton|Data1={{dts|1833|1|1|abbr=on}}|Data2=Columbiana, Stark, Harrison, Jefferson, and Tuscarawas Counties|Data3=[[Charles Carroll of Carrollton|Charles Carroll]] (1737–1832), last surviving signer of the [[United States Declaration of Independence]]|Population=26460|Area=394.67|Size=100px}}
{{Countyrow|Name=Champaign|N=39|Num=021|Seat=Urbana|Data1={{dts|1805|3|1|abbr=on}}|Data2=Greene and Franklin Counties|Data3=French for "a plain", describing the land in the area|Population=38907|Area=428.56|Size=100px}}
{{Countyrow|Name=Clark|N=39|Num=023|Seat=Springfield|Data1={{dts|1818|3|1|abbr=on}}|Data2=Champaign, Madison, and Greene Counties|Data3=General [[George Rogers Clark]] (1752–1818), defeated the [[Shawnee]] Indians in a battle near the [[Springfield, Ohio|Springfield]] area|Population=134985|Area=399.86|Size=100px}}
{{Countyrow|Name=Clermont|N=39|Num=025|Seat=Batavia|Data1={{dts|1800|12|6|abbr=on}}|Data2=Hamilton County|Data3=French for "clear mountain"|Population=214123|Area=451.99|Size=100px}}
{{Countyrow|Name=Clinton|N=39|Num=027|Seat=Wilmington|Data1={{dts|1810|3|1|abbr=on}}|Data2=Highland and Warren Counties|Data3=[[George Clinton (vice president)|George Clinton]] (1739–1812), vice-president when the county was organized| Population=42019|Area=410.88|Size=100px}}
{{Countyrow|Name=Columbiana|N=39|Num=029|Seat=Lisbon|Data1={{dts|1803|5|1|abbr=on}}|Data2=Jefferson and Washington Counties|Data3=[[Christopher Columbus]], European explorer of the Americas|Population=99823|Area=532.46|Size=100px}}
{{Countyrow|Name=Coshocton|N=39|Num=031|Seat=Coshocton|Data1={{dts|1810|1|31|abbr=on}}|Data2=Muskingum and Tuscarawas Counties|Data3=[[Delaware language|Delaware]] Indian word meaning "union of waters"|Population=37003|Area=564.07|Size=100px}}
{{Countyrow|Name=Crawford|N=39|Num=033|Seat=Bucyrus|Data1={{dts|1820|4|1|abbr=on}}|Data2=Delaware County|Data3=Colonel [[William Crawford (soldier)|William Crawford]] (1732–1782), [[American Revolutionary War|Revolutionary War]] officer|Population=41626|Area=402.11|Size=100px}}
{{Countyrow|Name=Cuyahoga|N=39|Num=035|Seat=Cleveland|Data1={{dts|1807|6|7|abbr=on}}|Data2=Geauga County|Data3=[[Cuyahoga River]], which means "crooked river" in an [[Iroquoian languages|Iroquoian language]]<ref>[https://www.britannica.com/eb/article-9028349/Cuyahoga-River Cuyahoga River], [[Encyclopædia Britannica]], 2007.  Accessed November 19, 2007.</ref>|Population=1240594|Area=458.49|Size=100px}}
{{Countyrow|Name=Darke|N=39|Num=037|Seat=Greenville|Data1={{dts|1809|1|3|abbr=on}}|Data2=Miami County|Data3=General [[William Darke]] (1736–1801), [[American Revolutionary War|Revolutionary War]] officer|Population=51462|Area=599.80|Size=100px}}
{{Countyrow|Name=Defiance|N=39|Num=039|Seat=Defiance|Data1={{dts|1845|4|7|abbr=on}}|Data2=Williams, Henry, and Paulding Counties|Data3=[[Fort Defiance (Ohio)|Fort Defiance]], built in 1794 by General [[Anthony Wayne]]|Population=38644|Area=411.16|Size=100px}}
{{Countyrow|Name=Delaware|N=39|Num=041|Seat=Delaware|Data1={{dts|1808|4|1|abbr=on}}|Data2=Franklin County|Data3=[[Delaware Indians]]|Population=237966|Area=442.41|Size=100px}}
{{Countyrow|Name=Erie|N=39|Num=043|Seat=Sandusky|Data1={{dts|1838|3|15|abbr=on}}|Data2=Huron and Sandusky Counties|Data3=[[Erie Indians]]|Population=73841|Area=254.88|Size=100px}}
{{Countyrow|Name=Fairfield|N=39|Num=045|Seat=Lancaster|Data1={{dts|1800|12|9|abbr=on}}|Data2=Ross and Washington Counties|Data3=Named for the beauty of its "fair fields"|Population=167762|Area=505.11|Size=100px}}
{{Countyrow|Name=Fayette|N=39|Num=047|Seat=Washington Court House|Data1={{dts|1810|3|1|abbr=on}}|Data2=Ross and Highland Counties|Data3=[[Gilbert du Motier, marquis de La Fayette]], French military officer and aristocrat who participated in both the American and French revolutions|Population=28782|Area=406.58|Size=100px}}
{{Countyrow|Name=Franklin|N=39|Num=049|Seat=Columbus|Data1={{dts|1803|4|30|abbr=on}}|Data2=Ross and Wayne Counties|Data3=[[Benjamin Franklin]] (1706–1791), [[Founding Fathers of the United States|Founding Father]], author, printer, political theorist, scientist, inventor, and statesman |Population=1356303|Area=539.87|Size=100px}}
{{Countyrow|Name=Fulton|N=39|Num=051|Seat=Wauseon|Data1={{dts|1850|4|1|abbr=on}}|Data2=Lucas, Henry, and Williams Counties|Data3=[[Robert Fulton]] (1765–1815), inventor of the [[steamboat]]<ref>[https://www.fultoncountyoh.com/101/About-Fulton-County About Fulton County]</ref>|Population=42028|Area=406.78|Size=100px}}
{{Countyrow|Name=Gallia|N=39|Num=053|Seat=Gallipolis|Data1={{dts|1803|4|30|abbr=on}}|Data2=Washington and Adams Counties|Data3=[[Gaul]], the ancient name of [[France]]|Population=28886|Area=468.78|Size=100px}}
{{Countyrow|Name=Geauga|N=39|Num=055|Seat=Chardon|Data1={{dts|1806|3|1|abbr=on}}|Data2=Trumbull County|Data3=A native american word meaning "raccoon"|Population=95362|Area=403.66|Size=100px}}
{{Countyrow|Name=Greene|N=39|Num=057|Seat=Xenia|Data1={{dts|1803|5|1|abbr=on}}|Data2=Hamilton and Ross Counties|Data3=General [[Nathanael Greene]] (1742–1786), [[American Revolutionary War|Revolutionary War]] officer|Population=172347|Area=414.88|Size=100px}}
{{Countyrow|Name=Guernsey|N=39|Num=059|Seat=Cambridge|Data1={{dts|1810|3|1|abbr=on}}|Data2=Belmont and Muskingum Counties|Data3=Island of [[Guernsey]], from where most of the settlers originated|Population=38219|Area=521.90|Size=100px}}
{{Countyrow|Name=Hamilton|N=39|Num=061|Seat=Cincinnati|Data1={{dts|1790|1|2|abbr=on}}|Data2=One of the original counties|Data3=[[Alexander Hamilton]] (1755/7-1804), [[United States Secretary of the Treasury|Secretary of the Treasury]] when the county was organized|Population=837359|Area=407.36|Size=100px}}
{{Countyrow|Name=Hancock|N=39|Num=063|Seat=Findlay|Data1={{dts|1820|4|1|abbr=on}}|Data2=Logan County|Data3=[[John Hancock]] (1737–1793), president of the [[Continental Congress]]|Population=75016|Area=531.35|Size=100px}}
{{Countyrow|Name=Hardin|N=39|Num=065|Seat=Kenton|Data1={{dts|1820|4|1|abbr=on}}|Data2=Logan County|Data3=General [[John Hardin]] (1753–1792), [[American Revolutionary War|Revolutionary War]] officer|Population=30402|Area=470.29|Size=100px}}
{{Countyrow|Name=Harrison|N=39|Num=067|Seat=Cadiz|Data1={{dts|1813|2|1|abbr=on}}|Data2=Jefferson and Tuscarawas Counties|Data3=General [[William Henry Harrison]] (1773–1841), an officer of the [[War of 1812]] and future [[President of the United States]]|Population=14042|Area=403.53|Size=100px}}
{{Countyrow|Name=Henry|N=39|Num=069|Seat=Napoleon|Data1={{dts|1820|4|1|abbr=on}}|Data2=Shelby County|Data3=[[Patrick Henry]] (1736–1799), [[American Revolutionary War|Revolutionary War]]-era legislator, orator, and scholar|Population=27536|Area=416.50|Size=100px}}
{{Countyrow|Name=Highland|N=39|Num=071|Seat=Hillsboro|Data1={{dts|1805|5|1|abbr=on}}|Data2=Ross, Adams, and Clermont Counties|Data3=Descriptive of the county's terrain|Population=43785|Area=553.28|Size=100px}}
{{Countyrow|Name=Hocking|N=39|Num=073|Seat=Logan|Data1={{dts|1818|3|1|abbr=on}}|Data2=Athens, Ross, and Fairfield Counties|Data3=Possibly derived from the [[Delaware Indian]] word "Hoch-Hoch-ing", meaning "bottle"|Population=27429|Area=422.75|Size=100px}}
{{Countyrow|Name=Holmes|N=39|Num=075|Seat=Millersburg|Data1={{dts|1824|1|20|abbr=on}}|Data2=Coshocton, Wayne, and Tuscarawas Counties|Data3=Major [[Andrew Holmes (army officer)|Andrew Holmes]] (died 1814), a [[War of 1812]] officer|Population=44668|Area=422.99|Size=100px}}
{{Countyrow|Name=Huron|N=39|Num=077|Seat=Norwalk|Data1={{dts|1809|3|7|abbr=on}}|Data2=Portage and Cuyahoga Counties|Data3=[[Wyandot people|Huron Indians]]|Population=58168|Area=492.69|Size=100px}}
{{Countyrow|Name=Jackson|N=39|Num=079|Seat=Jackson|Data1={{dts|1816|3|1|abbr=on}}|Data2=Scioto, Gallia, Athens, and Ross Counties|Data3=General [[Andrew Jackson]] (1767–1845), future President of the United States |Population=32723|Area=420.28|Size=100px}}
{{Countyrow|Name=Jefferson|N=39|Num=081|Seat=Steubenville|Data1={{dts|1797|7|29|abbr=on}}|Data2=Washington County|Data3=[[Thomas Jefferson]] (1743–1826), [[Vice President of the United States|Vice President]] when the county was organized, future [[President of the United States]], and principal author of the [[United States Declaration of Independence|Declaration of Independence]] |Population=63900|Area=409.61|Size=100px}}
{{Countyrow|Name=Knox|N=39|Num=083|Seat=Mount Vernon|Data1={{dts|1808|3|1|abbr=on}}|Data2=Fairfield County|Data3=General [[Henry Knox]], the first [[United States Secretary of War|Secretary of War]]|Population=63848|Area=527.12|Size=100px}}
{{Countyrow|Name=Lake|N=39|Num=085|Seat=Painesville|Data1={{dts|1840|3|6|abbr=on}}|Data2=Geauga and Cuyahoga Counties|Data3=Its location on [[Lake Erie]]|Population=232360|Area=228.21|Size=100px}}
{{Countyrow|Name=Lawrence|N=39|Num=087|Seat=Ironton|Data1={{dts|1815|12|21|abbr=on}}|Data2=Gallia and Scioto Counties|Data3=Captain [[James Lawrence]] (1781–1813), naval hero in the [[War of 1812]]| Population=55829 |Area=454.96|Size=100px}}
{{Countyrow|Name=Licking|N=39|Num=089|Seat=Newark|Data1={{dts|1808|3|1|abbr=on}}|Data2=Fairfield County|Data3=[[Licking River (Ohio)|Licking River]], named for the [[salt licks]] in the area, or an English pronunciation of the [[Lenape]] word ''W'li/'ik'/nk'' meaning "where the flood waters recede"<ref>{{cite journal |last1=Mahr |first1=August C. |title=Indian River and Place Names in Ohio |journal=Ohio Archaeological and Historical Quarterly |date=April 1957 |volume=66 |issue=2 |pages=146–148 |url=https://resources.ohiohistory.org/ohj/search/display.php?page=10&ipp=20&vol=66&pages=137-158 |ref=IndianRiver}}</ref>|Population=184898|Area=686.50|Size=100px}}
{{Countyrow|Name=Logan|N=39|Num=091|Seat=Bellefontaine|Data1={{dts|1818|3|1|abbr=on}}|Data2=Champaign County|Data3=General [[Benjamin Logan]] ({{Circa|1742}} – 1802), who destroyed [[Shawnee Indian]] towns in the county|Population=46085|Area=458.44|Size=100px}}
{{Countyrow|Name=Lorain|N=39|Num=093|Seat=Elyria|Data1={{dts|1822|12|26|abbr=on}}|Data2=Huron, Cuyahoga, and Medina Counties|Data3=Province of [[Lorraine (province)|Lorraine]], [[France]]|Population=322030|Area=492.50|Size=100px}}
{{Countyrow|Name=Lucas|N=39|Num=095|Seat=Toledo|Data1={{dts|1835|6|20|abbr=on}}|Data2=Wood, Sandusky, and Huron Counties|Data3=[[Robert Lucas (governor)|Robert Lucas]] (1781–1853), [[Governor of Ohio]] when the county was created|Population=426291|Area=340.46|Size=100px}}
{{Countyrow|Name=Madison|N=39|Num=097|Seat=London|Data1={{dts|1810|3|1|abbr=on}}|Data2=Franklin County|Data3=[[James Madison]] (1751–1836), fourth [[President of the United States]]|Population=45531|Area=465.44|Size=100px}}
{{Countyrow|Name=Mahoning|N=39|Num=099|Seat=Youngstown|Data1={{dts|1846|3|1|abbr=on}}|Data2=Columbiana and Trumbull Counties|Data3=[[Mahoning River]], from a [[Lenape]] word meaning "at the licks"|Population=225786|Area=415.25|Size=100px}}
{{Countyrow|Name=Marion|N=39|Num=101|Seat=Marion|Data1={{dts|1820|4|1|abbr=on}}|Data2=Delaware County|Data3=General [[Francis Marion]] (1732–1795), lieutenant colonel in the [[Continental Army]] and later brigadier general in the [[American Revolutionary War]]|Population=64976|Area=403.84|Size=100px}}
{{Countyrow|Name=Medina|N=39|Num=103|Seat=Medina|Data1={{dts|1812|2|18|abbr=on}}|Data2=Portage County|Data3=[[Medina]], world-renowned religious site in western [[Saudi Arabia]]|Population=184625|Area=423|Size=100px}}
{{Countyrow|Name=Meigs|N=39|Num=105|Seat=Pomeroy|Data1={{dts|1819|4|1|abbr=on}}|Data2=Gallia and Athens Counties|Data3=[[Return Jonathan Meigs Jr.]] (1764–1825), [[Governor of Ohio]] and [[United States Postmaster General|Postmaster General]] at the time the county was organized|Population=21491|Area=429.42|Size=100px}}
{{Countyrow|Name=Mercer|N=39|Num=107|Seat=Celina|Data1={{dts|1820|4|1|abbr=on}}|Data2=Darke County|Data3=General [[Hugh Mercer]] (1726–1777), a [[American Revolutionary War|Revolutionary War]] officer|Population=42648|Area=463.27|Size=100px}}
{{Countyrow|Name=Miami|N=39|Num=109|Seat=Troy|Data1={{dts|1807|3|1|abbr=on}}|Data2=Montgomery County|Data3=[[Miami Indians]]|Population=111950|Area=407.04|Size=100px}}
{{Countyrow|Name=Monroe|N=39|Num=111|Seat=Woodsfield|Data1={{dts|1813|1|29|abbr=on}}|Data2=Belmont, Washington, and Guernsey Counties|Data3=[[James Monroe]] (1758–1831), [[United States Secretary of State|Secretary of State]] when the county was organized and future [[President of the United States]]|Population=13051|Area=455.54|Size=100px}}
{{Countyrow|Name=Montgomery|N=39|Num=113|Seat=Dayton|Data1={{dts|1803|5|1|abbr=on}}|Data2=Hamilton and Wayne Counties|Data3=General [[Richard Montgomery]] (1738–1775), a [[American Revolutionary War|Revolutionary War]] officer|Population=537443|Area=461.68|Size=100px}}
{{Countyrow|Name=Morgan|N=39|Num=115|Seat=McConnelsville|Data1={{dts|1817|12|29|abbr=on}}|Data2=Washington, Guernsey, and Muskingum Counties|Data3=General [[Daniel Morgan]] (c. 1735 – 1802), a [[American Revolutionary War|Revolutionary War]] officer|Population=13532|Area=417.66|Size=100px}}
{{Countyrow|Name=Morrow|N=39|Num=117|Seat=Mount Gilead|Data1={{dts|1848|3|1|abbr=on}}|Data2=Knox, Marion, Delaware, and Richland Counties|Data3=[[Jeremiah Morrow]] (1771–1852), [[Governor of Ohio]]|Population=35927|Area=406.22|Size=100px}}
{{Countyrow|Name=Muskingum|N=39|Num=119|Seat=Zanesville|Data1=March 1, 1804{{sfn|Downes|p=368}}{{sfn|Taylor & Taylor|p=40}}|Data2=Washington and Fairfield Counties|Data3=An Indian word meaning "A town by the river" or "by the river side"|Population=86582|Area=664.63|Size=100px}}
{{Countyrow|Name=Noble|N=39|Num=121|Seat=Caldwell|Data1={{dts|1851|4|1|abbr=on}}|Data2=Monroe, Washington, Morgan, and Guernsey Counties|Data3=James Noble, an early settler in the area|Population=14269|Area=399.00|Size=100px}}
{{Countyrow|Name=Ottawa|N=39|Num=123|Seat=Port Clinton|Data1={{dts|1840|3|6|abbr=on}}|Data2=Erie, Sandusky, and Lucas Counties|Data3=Named for the [[Ottawa Indians]]; Ottawa means "trader" in their language|Population=39692|Area=254.95|Size=100px}}
{{Countyrow|Name=Paulding|N=39|Num=125|Seat=Paulding|Data1={{dts|1820|4|1|abbr=on}}|Data2=Darke County|Data3=[[John Paulding]]  (1758–1818), captor of spy [[John André]] during the [[American Revolutionary War|Revolutionary War]]|Population=18755|Area=416.26|Size=100px}}
{{Countyrow|Name=Perry|N=39|Num=127|Seat=New Lexington|Data1={{dts|1818|3|1|abbr=on}}|Data2=Washington, Fairfield, and Muskingum Counties|Data3=Commodore [[Oliver Hazard Perry]] (1785–1819), a naval officer of the [[War of 1812]]|Population=35682|Area=409.78|Size=100px}}
{{Countyrow|Name=Pickaway|N=39|Num=129|Seat=Circleville|Data1={{dts|1810|3|1|abbr=on}}|Data2=Ross, Fairfield, and Franklin Counties|Data3=A misspelling of the [[Pekowi|Piqua]] tribe, a branch of the [[Shawnee]]|Population=62158|Area=501.91|Size=100px}}
{{Countyrow|Name=Pike|N=39|Num=131|Seat=Waverly|Data1={{dts|1815|2|1|abbr=on}}|Data2=Ross, Scioto, and Adams Counties|Data3=General [[Zebulon M. Pike]] (1779–1813), a [[War of 1812]] officer and discoverer of [[Pikes Peak]] in Colorado in 1806|Population=27065|Area=441.49|Size=100px}}
{{Countyrow|Name=Portage|N=39|Num=133|Seat=Ravenna|Data1={{dts|1807|6|7|abbr=on}}|Data2=Trumbull County|Data3=Derived from an Indian [[portage]]|Population=163839|Area=492.39|Size=100px}}
{{Countyrow|Name=Preble|N=39|Num=135|Seat=Eaton|Data1={{dts|1808|3|1|abbr=on}}|Data2=Montgomery and Butler Counties|Data3=Captain [[Edward Preble]] (1761–1807), a Naval commander in the [[American Revolutionary War|Revolutionary War]]|Population=40801|Area=424.80|Size=100px}}
{{Countyrow|Name=Putnam|N=39|Num=137|Seat=Ottawa|Data1={{dts|1820|4|1|abbr=on}}|Data2=Shelby County|Data3=General [[Israel Putnam]] (1718–1790), a [[American Revolutionary War|Revolutionary War]] officer|Population=34206|Area=483.87|Size=100px}}
{{Countyrow|Name=Richland|N=39|Num=139|Seat=Mansfield|Data1={{dts|1808|3|1|abbr=on}}|Data2=Fairfield County|Data3=Descriptive of the soil in the area|Population=124853|Area=496.88|Size=100px}}
{{Countyrow|Name=Ross|N=39|Num=141|Seat=Chillicothe|Data1={{dts|1798|8|20|abbr=on}}|Data2=Adams and Washington Counties|Data3=Named for U.S. Senator from [[Pennsylvania]] [[James Ross (Pennsylvania congressman)|James Ross]] by territorial governor [[Arthur St. Clair]] |Population=76046|Area=688.41|Size=100px}}
{{Countyrow|Name=Sandusky|N=39|Num=143|Seat=Fremont|Data1={{dts|1820|4|1|abbr=on}}|Data2=Huron County|Data3=An [[Iroquois]] word meaning "cold water"|Population=58866|Area=409.18|Size=100px}}
{{Countyrow|Name=Scioto|N=39|Num=145|Seat=Portsmouth|Data1={{dts|1803|5|1|abbr=on}}|Data2=Adams County|Data3=[[Scioto River]]; Scioto is a [[Wyandot people|Wyandot]] Indian word meaning "deer"|Population=71798|Area=612.27|Size=100px}}
{{Countyrow|Name=Seneca|N=39|Num=147|Seat=Tiffin|Data1={{dts|1820|4|1|abbr=on}}|Data2=Huron County|Data3=[[Seneca nation|Seneca]] Indians, who had a reservation in the county area at the time|Population=54730|Area=550.59|Size=100px}}
{{Countyrow|Name=Shelby|N=39|Num=149|Seat=Sidney|Data1={{dts|1819|4|1|abbr=on}}|Data2=Miami County|Data3=General [[Isaac Shelby]] (1750–1826), a [[American Revolutionary War|Revolutionary War]] officer and [[Governor of Kentucky]]|Population=47952|Area=409.27|Size=100px}}
{{Countyrow|Name=Stark|N=39|Num=151|Seat=Canton|Data1={{dts|1808|2|13|abbr=on}}|Data2=Columbiana County|Data3=General [[John Stark]] (1728–1822), a [[American Revolutionary War|Revolutionary War]] officer; known as the "Hero of Bennington" for his exemplary service at the [[Battle of Bennington]] in 1777|Population=374091|Area=576.14|Size=100px}}
{{Countyrow|Name=Summit|N=39|Num=153|Seat=Akron|Data1={{dts|1840|3|3|abbr=on}}|Data2=Medina, Portage, and Stark Counties|Data3=Its location at the highest elevation along the [[Ohio and Erie Canal]]|Population=538370|Area=419.38|Size=100px}}
{{Countyrow|Name=Trumbull|N=39|Num=155|Seat=Warren|Data1={{dts|1800|7|10|abbr=on}}|Data2=Jefferson and Wayne Counties|Data3=[[Jonathan Trumbull]] (1710–1785), Governor of Connecticut when the county was organized|Population=200300|Area=616.48|Size=100px}}
{{Countyrow|Name=Tuscarawas|N=39|Num=157|Seat=New Philadelphia|Data1={{dts|1808|3|15|abbr=on}}|Data2=Muskingum County|Data3=[[Tuscarawas River]], meaning "open mouth river"<br />'''or'''<br />the Tuscarawas tribe who lived on the river|Population=92048|Area=567.58|Size=100px}}
{{Countyrow|Name=Union|N=39|Num=159|Seat=Marysville|Data1={{dts|1820|4|1|abbr=on}}|Data2=Delaware, Franklin, Logan, and Madison Counties|Data3=Its formation by a union of four counties|Population=71721|Area=436.65|Size=100px}}
{{Countyrow|Name=Van Wert|N=39|Num=161|Seat=Van Wert|Data1={{dts|1820|4|1|abbr=on}}|Data2=Darke County|Data3=[[Isaac Van Wart]] (1760–1828), captor of spy [[John André]] during the [[American Revolutionary War|Revolutionary War]]|Population=28887|Area=410.09|Size=100px}}
{{Countyrow|Name=Vinton|N=39|Num=163|Seat=McArthur|Data1={{dts|1850|3|23|abbr=on}}|Data2=Athens, Gallia, Hocking, Jackson, and Ross Counties|Data3=[[Samuel Finley Vinton]] (1792–1862), Ohio Statesman and U.S. Congressman|Population=12545|Area=414.08|Size=100px}}
{{Countyrow|Name=Warren|N=39|Num=165|Seat=Lebanon|Data1={{dts|1803|5|1|abbr=on}}|Data2=Hamilton County|Data3=General [[Joseph Warren]] (1741–1775), a [[American Revolutionary War|Revolutionary War]] officer|Population=256059|Area=399.63|Size=100px}}
{{Countyrow|Name=Washington|N=39|Num=167|Seat=Marietta|Data1={{dts|1788|7|27|abbr=on}}|Data2=One of the original counties|Data3=[[George Washington]] (1732–1799), commander of the [[Continental Army]], president of the [[Philadelphia Convention|Constitutional Convention]], and future [[President of the United States]] |Population=58332|Area=635.15|Size=100px}}
{{Countyrow|Name=Wayne|N=39|Num=169|Seat=Wooster|Data1={{dts|1812|3|1|abbr=on}}|Data2=Stark County|Data3=General [[Anthony Wayne]] (1745–1796), a [[American Revolutionary War|Revolutionary War]] officer|Population=116632|Area=555.36|Size=100px}}
{{Countyrow|Name=Williams|N=39|Num=171|Seat=Bryan|Data1={{dts|1820|4|1|abbr=on}}|Data2=Darke County|Data3=[[David Williams (soldier)|David Williams]] (1754–1831), captor of spy [[John André]] during the [[American Revolutionary War|Revolutionary War]]|Population=36554|Area=421.74|Size=100px}}
{{Countyrow|Name=Wood|N=39|Num=173|Seat=Bowling Green|Data1={{dts|1820|4|1|abbr=on}}|Data2=Refactored from non-county territory|Data3=[[Eleazer D. Wood]] (1783–1814), founder of [[Fort Meigs]]|Population=133077|Area=617.32|Size=100px}}
{{Countyrow|Name=Wyandot|N=39|Num=175|Seat=Upper Sandusky|Data1={{dts|1845|2|3|abbr=on}}|Data2=Marion, Crawford, and Hardin Counties|Data3=[[Wyandot people|Wyandot]] Indians|Population=21394|Area=405.61|Size=100px}}
|}

==List of county codes==
The [[Federal Information Processing Standard]] (FIPS) is used by the U.S. government to uniquely identify counties. In the following table, these codes link to the United States Census Bureau's "quick facts" for each county. Ohio's FIPS code of 39 is used to distinguish from counties in other states. For example, Adams County's unique nationwide identifier is 39001.<ref name=FIPS>{{cite web |url=https://www.epa.gov/enviro/county-fips-code-listing-state-ohio |title=County FIPS Code Listing for the State of OHIO |publisher=United States Environmental Protection Agency |access-date=July 9, 2016}}</ref>

Various state agencies identify counties by different coding schemes. The [[Ohio Department of Taxation]] assigns [[Vehicle registration plates of Ohio#List of county numbers|consecutive numbers]] for the purpose of enumerating taxing districts.<ref name="ODT">{{cite web|title=Ohio Counties with County Number|location=Columbus, Ohio|date=June 25, 2020|accessdate=September 11, 2023|publisher=Ohio Department of Taxation|url=https://tax.ohio.gov/static/excise/Ohio%20County%20Listing.pdf}}</ref> The [[Ohio Department of Public Safety]], including the [[Ohio Bureau of Motor Vehicles]], associates these county numbers with vehicle registrations.<ref name="ODPS">{{cite book|title=Taxing District Code Book 2023|publisher=Ohio Bureau of Motor Vehicles, Tax Distribution Section|date=January 3, 2023|accessdate=September 12, 2023|url=https://publicsafety.ohio.gov/static/Taxing-District-Code-Book.pdf}}</ref> The [[Ohio Department of Transportation|Department of Transportation]] uses three-letter abbreviations in road inventory and traffic management applications.<ref name="ODOT">{{cite web|title=ODOT County Abbreviation Table|publisher=Ohio Department of Transportation|date=May 1, 2013|access-date=December 21, 2014|url=http://www.dot.state.oh.us/Divisions/Planning/TechServ/TIM/Documents/SLD/ODOT_County_Abbreviation_Table.pdf}}</ref> For historic preservation purposes, [[Ohio History Connection]] refers to counties by two- and three-letter abbreviations in the Ohio Archaeological Inventory and Ohio Historic Inventory, respectively.<ref name="OHPO">{{cite news |title=Ohio Archaeological Inventory Form Instruction Manual |publisher=[[Ohio Historical Society|Ohio Historic Preservation Office]] |date=June 2003 |page=61|accessdate=September 12, 2023 |url=https://www.ohiohistory.org/wp-content/uploads/2022/01/OAI_Manual_rev_2003.pdf#page=61}}</ref>

{| class="wikitable sortable"
|-
! County !! {{abbr|FIPS|Federal Information Processing Standard}} code !! {{abbr|ODPS|Ohio Department of Public Safety}}<ref name="ODPS" />/{{abbr|ODT|Ohio Department of Taxation}}<ref name="ODT" /> code !! {{abbr|OAI|Ohio Archaeological Inventory}}<ref name="OHPO" /> code !! {{abbr|ODOT|Ohio Department of Transportation}}<ref name="ODOT" />/{{abbr|OHI|Ohio Historic Inventory}}<ref name="OHPO" /> code
|-
| [[Adams County, Ohio|Adams County]] || 001 || 01 || AD || ADA
|-
| [[Allen County, Ohio|Allen County]] || 003 || 02 || AL || ALL
|-
| [[Ashland County, Ohio|Ashland County]] || 005 || 03 || AS || ASD
|-
| [[Ashtabula County, Ohio|Ashtabula County]] || 007 || 04 || AB || ATB
|-
| [[Athens County, Ohio|Athens County]] || 009 || 05 || AT || ATH
|-
| [[Auglaize County, Ohio|Auglaize County]] || 011 || 06 || AU || AUG
|-
| [[Belmont County, Ohio|Belmont County]] || 013 || 07 || BL || BEL
|-
| [[Brown County, Ohio|Brown County]] || 015 || 08 || BR || BRO
|-
| [[Butler County, Ohio|Butler County]] || 017 || 09 || BU || BUT
|-
| [[Carroll County, Ohio|Carroll County]] || 019 || 10 || CA || CAR
|-
| [[Champaign County, Ohio|Champaign County]] || 021 || 11 || CH || CHP
|-
| [[Clark County, Ohio|Clark County]] || 023 || 12 || CL || CLA
|-
| [[Clermont County, Ohio|Clermont County]] || 025 || 13 || CT || CLE
|-
| [[Clinton County, Ohio|Clinton County]] || 027 || 14 || CN || CLI
|-
| [[Columbiana County, Ohio|Columbiana County]] || 029 || 15 || CO || COL
|-
| [[Coshocton County, Ohio|Coshocton County]] || 031 || 16 || CS || COS
|-
| [[Crawford County, Ohio|Crawford County]] || 033 || 17 || CR || CRA
|-
| [[Cuyahoga County, Ohio|Cuyahoga County]] || 035 || 18 || CU || CUY
|-
| [[Darke County, Ohio|Darke County]] || 037 || 19 || DA || DAR
|-
| [[Defiance County, Ohio|Defiance County]] || 039 || 20 || DE || DEF
|-
| [[Delaware County, Ohio|Delaware County]] || 041 || 21 || DL || DEL
|-
| [[Erie County, Ohio|Erie County]] || 043 || 22 || ER || ERI
|-
| [[Fairfield County, Ohio|Fairfield County]] || 045 || 23 || FA || FAI
|-
| [[Fayette County, Ohio|Fayette County]] || 047 || 24 || FE || FAY
|-
| [[Franklin County, Ohio|Franklin County]] || 049 || 25 || FR || FRA
|-
| [[Fulton County, Ohio|Fulton County]] || 051 || 26 || FU || FUL
|-
| [[Gallia County, Ohio|Gallia County]] || 053 || 27 || GA || GAL
|-
| [[Geauga County, Ohio|Geauga County]] || 055 || 28 || GE || GEA
|-
| [[Greene County, Ohio|Greene County]] || 057 || 29 || GR || GRE
|-
| [[Guernsey County, Ohio|Guernsey County]] || 059 || 30 || GU || GUE
|-
| [[Hamilton County, Ohio|Hamilton County]] || 061 || 31 || HA || HAM
|-
| [[Hancock County, Ohio|Hancock County]] || 063 || 32 || HK || HAN
|-
| [[Hardin County, Ohio|Hardin County]] || 065 || 33 || HR || HAR
|-
| [[Harrison County, Ohio|Harrison County]] || 067 || 34 || HN || HAS
|-
| [[Henry County, Ohio|Henry County]] || 069 || 35 || HY || HEN
|-
| [[Highland County, Ohio|Highland County]] || 071 || 36 || HI || HIG
|-
| [[Hocking County, Ohio|Hocking County]] || 073 || 37 || HO || HOC
|-
| [[Holmes County, Ohio|Holmes County]] || 075 || 38 || HS || HOL
|-
| [[Huron County, Ohio|Huron County]] || 077 || 39 || HU || HUR
|-
| [[Jackson County, Ohio|Jackson County]] || 079 || 40 || JA || JAC
|-
| [[Jefferson County, Ohio|Jefferson County]] || 081 || 41 || JE || JEF
|-
| [[Knox County, Ohio|Knox County]] || 083 || 42 || KN || KNO
|-
| [[Lake County, Ohio|Lake County]] || 085 || 43 || LA || LAK
|-
| [[Lawrence County, Ohio|Lawrence County]] || 087 || 44 || LE || LAW
|-
| [[Licking County, Ohio|Licking County]] || 089 || 45 || LI || LIC
|-
| [[Logan County, Ohio|Logan County]] || 091 || 46 || LO || LOG
|-
| [[Lorain County, Ohio|Lorain County]] || 093 || 47 || LN || LOR
|-
| [[Lucas County, Ohio|Lucas County]] || 095 || 48 || LU || LUC
|-
| [[Madison County, Ohio|Madison County]] || 097 || 49 || MA || MAD
|-
| [[Mahoning County, Ohio|Mahoning County]] || 099 || 50 || MH || MAH
|-
| [[Marion County, Ohio|Marion County]] || 101 || 51 || MN || MAR
|-
| [[Medina County, Ohio|Medina County]] || 103 || 52 || ME || MED
|-
| [[Meigs County, Ohio|Meigs County]] || 105 || 53 || MS || MEG
|-
| [[Mercer County, Ohio|Mercer County]] || 107 || 54 || MR || MER
|-
| [[Miami County, Ohio|Miami County]] || 109 || 55 || MI || MIA
|-
| [[Monroe County, Ohio|Monroe County]] || 111 || 56 || MO || MOE
|-
| [[Montgomery County, Ohio|Montgomery County]] || 113 || 57 || MY || MOT
|-
| [[Morgan County, Ohio|Morgan County]] || 115 || 58 || MG || MRG
|-
| [[Morrow County, Ohio|Morrow County]] || 117 || 59 || MW || MRW
|-
| [[Muskingum County, Ohio|Muskingum County]] || 119 || 60 || MU || MUS
|-
| [[Noble County, Ohio|Noble County]] || 121 || 61 || NO || NOB
|-
| [[Ottawa County, Ohio|Ottawa County]] || 123 || 62 || OT || OTT
|-
| [[Paulding County, Ohio|Paulding County]] || 125 || 63 || PA || PAU
|-
| [[Perry County, Ohio|Perry County]] || 127 || 64 || PE || PER
|-
| [[Pickaway County, Ohio|Pickaway County]] || 129 || 65 || PI || PIC
|-
| [[Pike County, Ohio|Pike County]] || 131 || 66 || PK || PIK
|-
| [[Portage County, Ohio|Portage County]] || 133 || 67 || PO || POR
|-
| [[Preble County, Ohio|Preble County]] || 135 || 68 || PR || PRE
|-
| [[Putnam County, Ohio|Putnam County]] || 137 || 69 || PU || PUT
|-
| [[Richland County, Ohio|Richland County]] || 139 || 70 || RI || RIC
|-
| [[Ross County, Ohio|Ross County]] || 141 || 71 || RO || ROS
|-
| [[Sandusky County, Ohio|Sandusky County]] || 143 || 72 || SA || SAN
|-
| [[Scioto County, Ohio|Scioto County]] || 145 || 73 || SC || SCI
|-
| [[Seneca County, Ohio|Seneca County]] || 147 || 74 || SE || SEN
|-
| [[Shelby County, Ohio|Shelby County]] || 149 || 75 || SH || SHE
|-
| [[Stark County, Ohio|Stark County]] || 151 || 76 || ST || STA
|-
| [[Summit County, Ohio|Summit County]] || 153 || 77 || SU || SUM
|-
| [[Trumbull County, Ohio|Trumbull County]] || 155 || 78 || TR || TRU
|-
| [[Tuscarawas County, Ohio|Tuscarawas County]] || 157 || 79 || TU || TUS
|-
| [[Union County, Ohio|Union County]] || 159 || 80 || UN || UNI
|-
| [[Van Wert County, Ohio|Van Wert County]] || 161 || 81 || VW || VAN
|-
| [[Vinton County, Ohio|Vinton County]] || 163 || 82 || VI || VIN
|-
| [[Warren County, Ohio|Warren County]] || 165 || 83 || WA || WAR
|-
| [[Washington County, Ohio|Washington County]] || 167 || 84 || WN || WAS
|-
| [[Wayne County, Ohio|Wayne County]] || 169 || 85 || WE || WAY
|-
| [[Williams County, Ohio|Williams County]] || 171 || 86 || WI || WIL
|-
| [[Wood County, Ohio|Wood County]] || 173 || 87 || WO || WOO
|-
| [[Wyandot County, Ohio|Wyandot County]] || 175 || 88 || WY || WYA
|}

==See also==
* [[Ohio county government]]
* [[List of Ohio townships]]
* [[Illinois County, Virginia]], the county that formerly covered all of present-day Ohio

==References==
{{reflist|30em}}

== Further reading ==
{{commons category|Counties of Ohio}}
* {{cite journal
 |journal     = [[Ohio Archaeological and Historical Publications]]
 |title       = Evolution of Ohio County Boundaries
 |first       = Randolph Chandler
 |last        = Downes
 |volume      = 36
 |pages       = 340–477
 |url         = http://publications.ohiohistory.org/ohj/browse/volumeresult.php?page=2&ipp=20&vol=36
 |url-status     = dead
 |archive-url  = https://web.archive.org/web/20141105013307/http://publications.ohiohistory.org/ohj/browse/volumeresult.php?page=2&ipp=20&vol=36
 |archive-date = November 5, 2014
}}
* {{cite book 
|title=Ohio statesmen and annals of progress: from the year 1788 to the year 1900 ... 
|first1=William Alexander 
|last1=Taylor 
|first2=Aubrey Clarence 
|last2=Taylor 
|ref={{sfnRef|Taylor & Taylor}}
|year=1899 
|publisher=State of Ohio 
|url=https://books.google.com/books?id=ztegAAAAMAAJ&q=Muskingum&pg=PA40 
}}
* {{cite web |last1=writer |first1=Statf |author-link1= |collaboration= |year=2022 |location= |title=OHIO COUNTY GOVERNMENT OVERVIEW |url=https://ce.naco.org//app/profiles/CountyGov/CountyGov_39000.pdf |url-access= |format= |department= |website=ce.naco.org |type= |language= |edition= |agency=National Association of Counties (NACo) |arxiv= |asin= |asin-tld= |bibcode= |bibcode-access= |biorxiv= |citeseerx= |doi= |doi-access= |eissn= |hdl= |hdl-access= |isbn= |ismn= |issn= |jfm= |jstor= |jstor-access= |lccn= |medrxiv= |mr= |oclc= |ol= |ol-access= |osti= |osti-access= |pmc= |pmid= |rfc= |sbn= |ssrn= |s2cid= |s2cid-access= |zbl= |id= |url-status= |archive-url= |archive-format= |archive-date= |access-date=January 3, 2025 |quote-page= |quote-pages= |quote= }}

{{U.S. Counties}}
{{Ohio}}

{{DEFAULTSORT:List Of Counties In Ohio}}
[[Category:Lists of counties of the United States by state|Ohio, counties in]]
[[Category:Ohio counties|*List]]
[[Category:Ohio geography-related lists|Counties]]