Every ZIP code in the United States, with weather, radar, trivia and the numbers behind it. Five digits since 1963!

ZIP stands for Zone Improvement Plan. The codes went live on July 1, 1963.The lowest ZIP code is 00501 — the IRS in Holtsville, New York.The highest ZIP code is 99950, in Ketchikan, Alaska.Type 07734 into a calculator and turn it upside down: hELLO. It is Keansburg, New Jersey.12345 belongs to one company: General Electric in Schenectady, New York.The first digit is a region: 0 is New England and New Jersey, 9 is the West Coast, Alaska and Hawaii.Mr. ZIP, the cartoon mailman, was the mascot that sold the idea to America.ZIP+4 arrived in 1983 and can narrow a ZIP down to one side of one block.A ZIP code is a mail route, not a place: plenty of them cross county and even state lines.Play ZIP Hunt: guess the secret ZIP code of the day in six tries.
zipcodes.pro — RANKINGS/IL/LARGEST-POPULATION

ZIP Codes With the Largest Population in Illinois

What this measures. Population of the Census tabulation area, ACS 5-year estimate. Source: Census American Community Survey, data release 2026-10-12.

# ZIP City County Population
1 60629 Chicago Cook 108,324
2 60618 Chicago Cook 91,901
3 60632 Chicago Cook 89,107
4 60647 Chicago Cook 84,749
5 60639 Chicago Cook 84,240
6 60804 Cicero Cook 82,797
7 60623 Chicago Cook 81,277
8 60608 Chicago Cook 80,737
9 60625 Chicago Cook 76,760
10 60617 Chicago Cook 74,790
11 60634 Chicago Cook 73,885
12 60085 Waukegan Lake 72,341
13 60657 Chicago Cook 71,904
14 60614 Chicago Cook 70,693
15 60641 Chicago Cook 68,894
16 60640 Chicago Cook 65,445
17 60620 Chicago Cook 64,871
18 60402 Berwyn Cook 63,721
19 60651 Chicago Cook 63,335
20 60073 Round Lake Lake 62,868
21 60609 Chicago Cook 62,028
22 60016 Des Plaines Cook 60,898
23 60628 Chicago Cook 60,431
24 60619 Chicago Cook 59,503
25 60505 Aurora Kane 57,199
26 60638 Chicago Cook 57,074
27 60453 Oak Lawn Cook 56,861
28 60056 Mount Prospect Cook 55,818
29 60630 Chicago Cook 55,486
30 60622 Chicago Cook 54,609
31 60616 Chicago Cook 54,308
32 61761 Normal McLean 54,075
33 60637 Chicago Cook 52,721
34 60148 Lombard DuPage 52,596
35 60613 Chicago Cook 52,244
36 60411 Chicago Heights Cook 52,175
37 60440 Bolingbrook Will 51,940
38 60004 Arlington Heights Cook 51,835
39 60120 Elgin Cook 51,225
40 60506 Aurora Kane 50,038
41 60626 Chicago Cook 49,662
42 60014 Crystal Lake McHenry 48,590
43 60123 Elgin Kane 48,379
44 60645 Chicago Cook 48,208
45 60435 Joliet Will 48,167
46 60649 Chicago Cook 48,056
47 60586 Plainfield Will 47,834
48 60126 Elmhurst DuPage 47,516
49 60644 Chicago Cook 47,210
50 60564 Naperville Will 47,016

Showing the top 50 of 1,396 ZIP codes in Illinois that have this figure . 60629 ranks 1st at 108,324, against 47,016 in 50th place.

Other rankings for Illinois

Cite this page

zipcodes.pro. “ZIP Codes With the Largest Population in Illinois.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/rankings/il/largest-population

Underlying data is public domain or openly licensed — sources, vintages and licences.