Illinois is divided into 102 counties, each governed by its own local administration responsible for various community services and regulations. This interactive map and search tools allow you to explore Illinois counties in depth, including detailed information on cities, towns, and ZIP codes within each county.

Interactive Map of All Illinois Counties

Click on any county below to explore more about it.

No.	County Name	Largest City	County Map & Zip Code
1	Adams	Quincy	Adams County Map Link
2	Alexander	Cairo	Alexander County Map Link
3	Bond	Greenville	Bond County Map Link
4	Boone	Belvidere	Boone County Map Link
5	Brown	Mount Sterling	Brown County Map Link
6	Bureau	Princeton	Bureau County Map Link
7	Calhoun	Hardin	Calhoun County Map Link
8	Carroll	Mount Carroll	Carroll County Map Link
9	Cass	Virginia	Cass County Map Link
10	Champaign	Urbana	Champaign County Map Link
11	Christian	Taylorville	Christian County Map Link
12	Clark	Marshall	Clark County Map Link
13	Clay	Clay City	Clay County Map Link
14	Clinton	Breese	Clinton County Map Link
15	Coles	Charleston	Coles County Map Link
16	Cook	Chicago	Cook County Map Link
17	Crawford	Robinson	Crawford County Map Link
18	Cumberland	Toledo	Cumberland County Map Link
19	DeKalb	DeKalb	DeKalb County Map Link
20	De Witt	Clinton	De Witt County Map Link
21	Douglas	Arcola	Douglas County Map Link
22	DuPage	Naperville	DuPage County Map Link
23	Edgar	Paris	Edgar County Map Link
24	Edwards	Albion	Edwards County Map Link
25	Effingham	Effingham	Effingham County Map Link
26	Fayette	Vandalia	Fayette County Map Link
27	Ford	Paxton	Ford County Map Link
28	Franklin	West Frankfort	Franklin County Map Link
29	Fulton	Lewistown	Fulton County Map Link
30	Gallatin	Gallatin	Gallatin County Map Link
31	Greene	Carrollton	Greene County Map Link
32	Grundy	Joliet	Grundy County Map Link
33	Hamilton	McLeansboro	Hamilton County Map Link
34	Hancock	Carthage	Hancock County Map Link
35	Hardin	Elizabethtown	Hardin County Map Link
36	Henderson	Oquawka	Henderson County Map Link
37	Henry	Cambridge	Henry County Map Link
38	Iroquois	Watseka	Iroquois County Map Link
39	Jackson	Carbondale	Jackson County Map Link
40	Jasper	Newton	Jasper County Map Link
41	Jefferson	Mount Vernon	Jefferson County Map Link
42	Jersey	Jerseyville	Jersey County Map Link
43	Jo Daviess	Galena	Jo Daviess County Map Link
44	Johnson	Vienna	Johnson County Map Link
45	Kane	Aurora	Kane County Map Link
46	Kankakee	Kankakee	Kankakee County Map Link
47	Kendall	Oswego	Kendall County Map Link
48	Knox	Galesburg	Knox County Map Link
49	Lake	Waukegan	Lake County Map Link
50	LaSalle	Ottawa	LaSalle County Map Link
51	Lawrence	Lawrenceville	Lawrence County Map Link
52	Lee	Amboy	Lee County Map Link
53	Livingston	Pontiac	Livingston County Map Link
54	Logan	Lincoln	Logan County Map Link
55	Macon	Decatur	Macon County Map Link
56	Macoupin	Carlinville	Macoupin County Map Link
57	Madison	Edwardsville	Madison County Map Link
58	Marion	Centralia	Marion County Map Link
59	Marshall	Lacon	Marshall County Map Link
60	Mason	Havana	Mason County Map Link
61	Massac	Metropolis	Massac County Map Link
62	McDonough	Macomb	McDonough County Map Link
63	McHenry	Woodstock	McHenry County Map Link
64	McLean	Bloomington	McLean County Map Link
65	Menard	Petersburg	Menard County Map Link
66	Mercer	Aledo	Mercer County Map Link
67	Monroe	Waterloo	Monroe County Map Link
68	Montgomery	Litchfield	Montgomery County Map Link
69	Morgan	Jacksonville	Morgan County Map Link
70	Moultrie	Dalton City	Moultrie County Map Link
71	Ogle	Oregon	Ogle County Map Link
72	Peoria	Peoria	Peoria County Map Link
73	Perry	Pinckneyville	Perry County Map Link
74	Piatt	Monticello	Piatt County Map Link
75	Pike	Pittsfield	Pike County Map Link
76	Pope	Golconda	Pope County Map Link
77	Pulaski	Mound City	Pulaski County Map Link
78	Putnam	Hennepin	Putnam County Map Link
79	Randolph	Chester	Randolph County Map Link
80	Richland	Olney	Richland County Map Link
81	Rock Island	Moline	Rock Island County Map Link
82	St. Clair	Belleville	St. Clair County Map Link
83	Saline	Harrisburg	Saline County Map Link
84	Sangamon	Springfield	Sangamon County Map Link
85	Schuyler	Rushville	Schuyler County Map Link
86	Scott	Winchester	Scott County Map Link
87	Shelby	Shelbyville	Shelby County Map Link
88	Stark	Wyoming	Stark County Map Link
89	Stephenson	Freeport	Stephenson County Map Link
90	Tazewell	East Peoria	Tazewell County Map Link
91	Union	Anna	Union County Map Link
92	Vermilion	Danville	Vermilion County Map Link
93	Wabash	Mount Carmel	Wabash County Map Link
94	Warren	Monmouth	Warren County Map Link
95	Washington	Nashville	Washington County Map Link
96	Wayne	Fairfield	Wayne County Map Link
97	White	Grayville	White County Map Link
98	Whiteside	Sterling	Whiteside County Map Link
99	Will	Joliet	Will County Map Link
100	Williamson	Marion	Williamson County Map Link
101	Winnebago	Rockford	Winnebago County Map Link
102	Woodford	East Peoria	Woodford County Map Link

Illinois County Map Download

You can download the Illinois County Map from below:

Frequently Asked Questions

The largest county in Illinois by land area is McLean County. It covers about 1,183 square miles, making it the biggest county in the state geographically.

The smallest county in Illinois by land area is Calhoun County. It covers about 284 square miles, making it the smallest county geographically in the state.

Illinois has 102 counties in total.

Source: Wikipedia, Census.gov