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/KY/HIGHEST-DENSITY

Most Densely Populated ZIP Codes in Kentucky

What this measures. People per square mile of land area. Source: Census American Community Survey and Gazetteer, data release 2026-10-12.

# ZIP City County People per sq mi
1 40526 Lexington Fayette 39,066
2 41014 Covington Kenton 7,319
3 41073 Bellevue Campbell 6,228
4 40203 Louisville Jefferson 6,129
5 40208 Louisville Jefferson 5,981
6 40215 Louisville Jefferson 5,881
7 40517 Lexington Fayette 5,777
8 40514 Lexington Fayette 5,673
9 40508 Lexington Fayette 5,647
10 40404 Berea Madison 5,626
11 40507 Lexington Fayette 5,009
12 40217 Louisville Jefferson 4,864
13 40220 Louisville Jefferson 4,580
14 40202 Louisville Jefferson 4,496
15 40204 Louisville Jefferson 4,422
16 40063 Saint Mary Marion 4,347
17 40041 Masonic Home Jefferson 4,339
18 40210 Louisville Jefferson 4,259
19 40504 Lexington Fayette 4,188
20 41074 Dayton Campbell 3,970
21 41016 Covington Kenton 3,913
22 40242 Louisville Jefferson 3,905
23 41011 Covington Kenton 3,839
24 40212 Louisville Jefferson 3,829
25 40218 Louisville Jefferson 3,748
26 40807 Benham Harlan 3,729
27 40502 Lexington Fayette 3,655
28 41071 Newport Campbell 3,588
29 40205 Louisville Jefferson 3,581
30 40206 Louisville Jefferson 3,451
31 41517 Burdine Letcher 3,243
32 40505 Lexington Fayette 3,204
33 40434 Gray Hawk Jackson 3,200
34 40503 Lexington Fayette 3,107
35 40214 Louisville Jefferson 3,034
36 41075 Fort Thomas Campbell 2,955
37 42356 Maple Mount Daviess 2,933
38 41268 West Van Lear Johnson 2,932
39 40243 Louisville Jefferson 2,922
40 40216 Louisville Jefferson 2,814
41 40339 Keene Jessamine 2,813
42 40211 Louisville Jefferson 2,792
43 40219 Louisville Jefferson 2,686
44 41042 Florence Boone 2,606
45 40280 Louisville Jefferson 2,563
46 41018 Erlanger Kenton 2,502
47 40207 Louisville Jefferson 2,463
48 40229 Louisville Jefferson 2,359
49 40241 Louisville Jefferson 2,344
50 40258 Louisville Jefferson 2,299

Showing the top 50 of 780 ZIP codes in Kentucky that have this figure . 40526 ranks 1st at 39,066, against 2,299 in 50th place.

Other rankings for Kentucky

Cite this page

zipcodes.pro. “Most Densely Populated ZIP Codes in Kentucky.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/rankings/ky/highest-density

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