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/ID/SMALLEST-AREA

Smallest ZIP Codes in Idaho by Land Area

What this measures. Land area of the Census tabulation area, smallest first. These are almost always dense urban ZIP codes covering a few city blocks. Source: Census Gazetteer, data release 2026-10-12.

# ZIP City County Land area
1 83720 Boise Ada 0.01 sq mi
2 83354 Sun Valley Blaine 0.02 sq mi
3 83438 Parker Fremont 0.05 sq mi
4 83725 Boise Ada 0.07 sq mi
5 83215 Atomic City Bingham 0.08 sq mi
6 83454 Ucon Bonneville 0.16 sq mi
7 83656 Notus Canyon 0.26 sq mi
8 83460 Rexburg Madison 0.29 sq mi
9 83840 Kootenai Bonner 0.30 sq mi
10 83203 Fort Hall Bingham 0.44 sq mi
11 83218 Basalt Bingham 0.45 sq mi
12 83825 Dover Bonner 0.54 sq mi
13 83844 Moscow Latah 0.59 sq mi
14 83209 Pocatello Bannock 0.67 sq mi
15 83433 Macks Inn Fremont 1.55 sq mi
16 83636 Letha Gem 2.49 sq mi
17 83852 Ponderay Bonner 2.50 sq mi
18 83223 Bloomington Bear Lake 3.10 sq mi
19 83643 Mesa Adams 3.48 sq mi
20 83867 Silverton Shoshone 4.21 sq mi
21 83626 Greenleaf Canyon 6.60 sq mi
22 83713 Boise Ada 6.60 sq mi
23 83868 Smelterville Shoshone 6.68 sq mi
24 83706 Boise Ada 7.43 sq mi
25 83703 Boise Ada 8.13 sq mi
26 83232 Dayton Franklin 8.25 sq mi
27 83277 Springfield Bingham 8.34 sq mi
28 83704 Boise Ada 8.75 sq mi
29 83353 Sun Valley Blaine 8.90 sq mi
30 83827 Elk River Clearwater 9.51 sq mi
31 83648 Mountain Home Afb Elmore 9.97 sq mi
32 83666 Placerville Boise 10.20 sq mi
33 83520 Ahsahka Clearwater 11.11 sq mi
34 83220 Bern Bear Lake 11.68 sq mi
35 83421 Chester Fremont 11.69 sq mi
36 83826 Eastport Boundary 11.77 sq mi
37 83431 Lewisville Jefferson 12.53 sq mi
38 83815 Coeur d'Alene Kootenai 15.62 sq mi
39 83651 Nampa Canyon 15.94 sq mi
40 83705 Boise Ada 16.21 sq mi
41 83451 Teton Madison 16.59 sq mi
42 83809 Careywood Bonner 16.91 sq mi
43 83849 Osburn Shoshone 17.70 sq mi
44 83842 Medimont Kootenai 19.05 sq mi
45 83602 Banks Boise 21.22 sq mi
46 83669 Star Ada 22.01 sq mi
47 83712 Boise Ada 22.95 sq mi
48 83237 Franklin Franklin 23.21 sq mi
49 83261 Paris Bear Lake 23.66 sq mi
50 83841 Laclede Bonner 23.91 sq mi

Showing the top 50 of 279 ZIP codes in Idaho that have this figure and meet the threshold above. 83720 ranks 1st at 0.01 sq mi, against 23.91 sq mi in 50th place.

Other rankings for Idaho

Cite this page

zipcodes.pro. “Smallest ZIP Codes in Idaho by Land Area.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/rankings/id/smallest-area

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