Counties in Illinois Cook County (Chicago) DuPage County (Wheaton) Lake County (Waukegan) Will County (Joliet) Kane County (Geneva) McHenry County (Woodstock) Winnebago County (Rockford) Madison County (Edwardsville) Saint Clair County (Belleville) Champaign County (Urbana) Sangamon County (Springfield) Peoria County (Peoria) McLean County (Bloomington) Rock Island County (Rock Island) Kendall County (Yorkville) Tazewell County (Pekin) La Salle County (Ottawa) Kankakee County (Kankakee) Macon County (Decatur) DeKalb County (Sycamore) Vermilion County (Danville) Williamson County (Marion) Adams County (Quincy) Whiteside County (Morrison) Boone County (Belvidere) Jackson County (Murphysboro) Grundy County (Morris) Ogle County (Oregon) Knox County (Galesburg) Henry County (Cambridge) Coles County (Charleston) Macoupin County (Carlinville) Stephenson County (Freeport) Woodford County (Eureka) Franklin County (Benton) Marion County (Salem) Jefferson County (Mount Vernon) Clinton County (Carlyle) Livingston County (Pontiac) Monroe County (Waterloo) Effingham County (Effingham) Lee County (Dixon) Christian County (Taylorville) Fulton County (Lewistown) Bureau County (Princeton) Morgan County (Jacksonville) Randolph County (Chester) Montgomery County (Hillsboro) Logan County (Lincoln) McDonough County (Macomb) Iroquois County (Watseka) Saline County (Harrisburg) Jo Daviess County (Galena) Jersey County (Jerseyville) Fayette County (Vandalia) Shelby County (Shelbyville) Perry County (Pinckneyville) Douglas County (Tuscola) Crawford County (Robinson) Hancock County (Carthage) Union County (Jonesboro) Edgar County (Paris) Warren County (Monmouth) Bond County (Greenville) Piatt County (Monticello) Wayne County (Fairfield) Richland County (Olney) Carroll County (Mount Carroll) Mercer County (Aledo) DeWitt County (Clinton) Clark County (Marshall) Lawrence County (Lawrenceville) Pike County (Pittsfield) Moultrie County (Sullivan) Massac County (Metropolis) White County (Carmi) Washington County (Nashville) Ford County (Paxton) Johnson County (Vienna) Clay County (Louisville) Mason County (Havana) Cass County (Virginia) Menard County (Petersburg) Greene County (Carrollton) Marshall County (Lacon) Wabash County (Mount Carmel) Cumberland County (Toledo) Jasper County (Newton) Hamilton County (McLeansboro) Schuyler County (Rushville) Henderson County (Oquawka) Edwards County (Albion) Brown County (Mount Sterling) Putnam County (Hennepin) Stark County (Toulon) Alexander County (Cairo) Pulaski County (Mound City) Scott County (Winchester) Gallatin County (Shawneetown) Calhoun County (Hardin) Pope County (Golconda) Hardin County (Elizabethtown)