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/IA/LARGEST-POPULATION

ZIP Codes With the Largest Population in Iowa

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 50023 Ankeny Polk 46,306
2 50613 Cedar Falls Black Hawk 43,867
3 52001 Dubuque Dubuque 43,101
4 52404 Cedar Rapids Linn 42,958
5 52402 Cedar Rapids Linn 42,938
6 52302 Marion Linn 42,706
7 52722 Bettendorf Scott 41,264
8 51503 Council Bluffs Pottawattamie 37,972
9 50266 West Des Moines Dallas 37,523
10 50317 Des Moines Polk 36,548
11 52240 Iowa City Johnson 35,074
12 50315 Des Moines Polk 34,816
13 51501 Council Bluffs Pottawattamie 34,618
14 50010 Ames Story 33,799
15 50265 West Des Moines Polk 33,488
16 50014 Ames Story 32,958
17 50322 Urbandale Polk 31,931
18 50158 Marshalltown Marshall 31,396
19 50310 Des Moines Polk 31,177
20 52501 Ottumwa Wapello 30,371
21 50021 Ankeny Polk 30,283
22 50701 Waterloo Black Hawk 30,232
23 50263 Waukee Dallas 29,611
24 52761 Muscatine Muscatine 29,474
25 50501 Fort Dodge Webster 28,823
26 50401 Mason City Cerro Gordo 28,703
27 51106 Sioux City Woodbury 28,592
28 52601 Burlington Des Moines 27,341
29 52806 Davenport Scott 26,871
30 52804 Davenport Scott 26,835
31 52405 Cedar Rapids Linn 26,526
32 52732 Clinton Clinton 25,880
33 50320 Des Moines Polk 24,807
34 50131 Johnston Polk 24,583
35 52241 Coralville Johnson 23,250
36 51104 Sioux City Woodbury 23,197
37 52317 North Liberty Johnson 23,097
38 50009 Altoona Polk 22,886
39 52245 Iowa City Johnson 22,853
40 52803 Davenport Scott 22,742
41 52403 Cedar Rapids Linn 22,551
42 52246 Iowa City Johnson 22,308
43 50702 Waterloo Black Hawk 20,882
44 50208 Newton Jasper 20,595
45 50125 Indianola Warren 20,121
46 50325 Clive Polk 19,012
47 50703 Waterloo Black Hawk 17,952
48 50313 Des Moines Polk 17,440
49 50323 Urbandale Dallas 17,265
50 52002 Dubuque Dubuque 17,005

Showing the top 50 of 970 ZIP codes in Iowa that have this figure . 50023 ranks 1st at 46,306, against 17,005 in 50th place.

Other rankings for Iowa

Cite this page

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

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