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/MT/LARGEST-AREA

Largest ZIP Codes in Montana by Land Area

What this measures. Land area of the Census tabulation area, in square miles. Water is excluded. Source: Census Gazetteer, data release 2026-10-12.

# ZIP City County Land area
1 59301 Miles City Custer 2,851.90 sq mi
2 59538 Malta Phillips 2,491.76 sq mi
3 59337 Jordan Garfield 2,116.85 sq mi
4 59327 Forsyth Rosebud 2,003.88 sq mi
5 59725 Dillon Beaverhead 1,959.82 sq mi
6 59645 White Sulphur Springs Meagher 1,630.51 sq mi
7 59523 Chinook Blaine 1,534.63 sq mi
8 59230 Glasgow Valley 1,496.93 sq mi
9 59936 West Glacier Flathead 1,480.08 sq mi
10 59923 Libby Lincoln 1,412.52 sq mi
11 59317 Broadus Powder River 1,405.64 sq mi
12 59427 Cut Bank Glacier 1,380.69 sq mi
13 59324 Ekalaka Carter 1,370.32 sq mi
14 59501 Havre Hill 1,345.40 sq mi
15 59215 Circle McCone 1,331.36 sq mi
16 59201 Wolf Point Roosevelt 1,313.06 sq mi
17 59349 Terry Prairie 1,305.24 sq mi
18 59072 Roundup Musselshell 1,291.32 sq mi
19 59087 Winnett Petroleum 1,277.23 sq mi
20 59241 Hinsdale Valley 1,219.03 sq mi
21 59422 Choteau Teton 1,190.57 sq mi
22 59410 Augusta Lewis and Clark 1,158.89 sq mi
23 59524 Dodson Phillips 1,120.65 sq mi
24 59520 Big Sandy Chouteau 1,120.39 sq mi
25 59336 Ismay Custer 1,046.99 sq mi
26 59353 Wibaux Wibaux 1,037.84 sq mi
27 59935 Troy Lincoln 1,035.55 sq mi
28 59761 Wisdom Beaverhead 1,035.20 sq mi
29 59471 Roy Fergus 1,026.10 sq mi
30 59739 Lima Beaverhead 1,017.61 sq mi
31 59330 Glendive Dawson 1,014.16 sq mi
32 59457 Lewistown Fergus 995.61 sq mi
33 59928 Polebridge Flathead 937.18 sq mi
34 59011 Big Timber Sweet Grass 936.36 sq mi
35 59313 Baker Fallon 906.01 sq mi
36 59347 Rosebud Rosebud 899.48 sq mi
37 59270 Sidney Richland 891.03 sq mi
38 59858 Philipsburg Granite 880.17 sq mi
39 59038 Hysham Treasure 879.54 sq mi
40 59829 Darby Ravalli 871.51 sq mi
41 59854 Ovando Powell 844.17 sq mi
42 59522 Chester Liberty 821.93 sq mi
43 59311 Alzada Carter 808.18 sq mi
44 59034 Hardin Big Horn 791.31 sq mi
45 59442 Fort Benton Chouteau 790.29 sq mi
46 59047 Livingston Park 781.31 sq mi
47 59873 Thompson Falls Sanders 769.35 sq mi
48 59261 Saco Phillips 761.74 sq mi
49 59014 Bridger Carbon 759.02 sq mi
50 59417 Browning Glacier 758.74 sq mi

Showing the top 50 of 369 ZIP codes in Montana that have this figure and meet the threshold above. 59301 ranks 1st at 2,851.90 sq mi, against 758.74 sq mi in 50th place.

Other rankings for Montana

Cite this page

zipcodes.pro. “Largest ZIP Codes in Montana by Land Area.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/rankings/mt/largest-area

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