Bates Established 1841 County Seat: Butler Communities: Adrian, Amoret, Amsterdam, Drexel, Foster, Hume, Merwin, Passaic, Rich Hill, Rockville Townships: Charlotte, Deepwater, Deer Creek, East Boone, Elkhart, Grand River, Homer, Howard, Hudson, Lone Oak, Mingo, Mound, Mount Pleasant, New Home, Osage, Pleasant Gap, Prairie, Rockville, Shawnee, Spruce, Summit, Walnut, West Boone, West Point
Benton Established 1835 County Seat: Warsaw Communities: Cole Camp, Edwards, Ionia, Lincoln, Mora Townships: Alexander, Cole, Lindsey, Tom, Union, White, Williams
Cass Established 1835 as Van Buren, renamed 1849 County Seat: Harrisonville Communities: Archie, Austin, Baldwin Park, Belton, Cleveland, Creighton, Drexel, East Lynne, Freeman, Garden City, Greenwood, Gunn City, Lake Annette, Lake Winnebago, Loch Lloyd, Peculiar, Pleasant Hill, Raymore, Strasburg, Villiage of Riverview Estates, West Line Townships: Austin, Big Creek, Camp Branch, Coldwater, Dolan, Everett, Grand River, Index, Mount Pleasant, Peculiar, Pleasant Hill, Polk, Raymore, Sherman, Union, West Dolan, West Peculiar
Henry Established 1834 County Seat: Clinton Communities: Blairstown, Brownington, Calhoun, Deepwater, Hartwell, La Due, Montrose, Tightwad, Urich, Windsor Townships: Bear Creek, Bethlehem, Big Creek, Bogard, Clinton, Davis, Deepwater, Deer Creek, Fairview, Fields Creek, Honey Creek, Leesville, Osage, Shawnee, Springfield, Tebo, Walker, White Oak, Windsor
Jackson Established 1826 County Seat: Independence and Kansas City Communities: Blue Springs, Blue Summit, Buckner, Grain Valley, Grandview, Greenwood, Lake Totawanna, Lake Tapawingo, Lee's Summit, Levasy, Lone Jack, Martin City, Oak Grove, Raytown, River Bend, Sibley, Sugar Creek, Unity Village Townships: Blue, Brooking, Fort Osage, Kaw, Prairie, Sni-A-Bar, Van Buren, Washington
Johnson Established 1834 County Seat: Warrensburg Communities: Centerview, Chilhowee, Holden, Kingsville, Knob Noster, La Tour, Leeton, Post Oak, Whiteman AFB Townships: Centerview, Chilhowee, Columbus, Grover, Hazel Hill, Jackson, Jefferson, Kingsville, Madison, Monsterrat, Post Oak, Simpson, Warrensburg, Washington
Lafayette Established 1820 as Lillard, renamed 1825 County Seat: Lexington Communities: Alma, Aullville, Bates City, Blackburn, Concordia, Corder, Dover, Emma, Higginsville, Lake Lafayette, Mayview, Napoleon, Oak Grove, Odessa, Waverly, Wellington Townships: Clay, Davis, Dover, Freedom, Lexington, Middleton, Sni-A-bar, Washington
Pettis Established 1833 County Seat: Sedalia Communities: Dresden, Green Ridge, Houstonia, Hughesville, Ionia, La Monte, Smithton, Windsor Townships: Blackwater, Bowling Green, Cedar, Dresden, Elk Fork, Flat Creek, Green Ridge, Heath's Creek, Houstonia, Hughesvill, La Monte, Lake Creek, Longwood, Mount Sterling (historical), Prairie, Sedalia, Smithton, Washington
Saline Established 1820 County Seat: Marshall Communities: Arrow Rock, Blackburn, Emma, Gilliam, Grand Pass, Malta Bend, Miami, Mount Leonard, Napton, Nelson, Pennytown, Slater, Sweet Springs Townships: Arrow Rock, Blackwater, Cambridge, Clay, Elmwood, Grand Pass, Liberty, Marshall, Miami, Salt Fork, Salt Pond
St. Clair Established 1841 County Seat: Osceola Communities: Appleton City, Lowry City, Collins, Gerster, Roscoe, Vista, Iconium, Taberville Townships: Appleton, Butler, Center, Chalk Level, Collins, Dallas, Doyle, Jackson, Monegaw, Osage, Osceola, Polk, Roscoe, Speedwell, Taber, Washington