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/NH/HIGHEST-DENSITY

Most Densely Populated ZIP Codes in New Hampshire

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 03060 Nashua Hillsborough 4,827
2 03104 Manchester Hillsborough 4,228
3 03101 Manchester Hillsborough 4,184
4 03103 Manchester Hillsborough 4,112
5 03102 Manchester Hillsborough 3,747
6 03064 Nashua Hillsborough 3,480
7 03062 Nashua Hillsborough 2,448
8 03063 Nashua Hillsborough 1,949
9 03109 Manchester Hillsborough 1,370
10 03842 Hampton Rockingham 1,277
11 03079 Salem Rockingham 1,246
12 03878 Somersworth Strafford 1,243
13 03820 Dover Strafford 1,226
14 03854 New Castle Rockingham 1,022
15 03801 Portsmouth Rockingham 988
16 03038 Derry Rockingham 961
17 03874 Seabrook Rockingham 949
18 03051 Hudson Hillsborough 904
19 03054 Merrimack Hillsborough 865
20 03246 Laconia Belknap 861
21 03867 Rochester Strafford 800
22 03826 East Hampstead Rockingham 775
23 03857 Newmarket Rockingham 751
24 03865 Plaistow Rockingham 742
25 03110 Bedford Hillsborough 724
26 03868 Rochester Strafford 701
27 03301 Concord Merrimack 691
28 03824 Durham Strafford 673
29 03811 Atkinson Rockingham 653
30 03055 Milford Hillsborough 643
31 03871 Rye Beach Rockingham 641
32 03053 Londonderry Rockingham 632
33 03841 Hampstead Rockingham 627
34 03087 Windham Rockingham 600
35 03609 North Walpole Cheshire 582
36 03052 Litchfield Hillsborough 570
37 03076 Pelham Hillsborough 549
38 03839 Rochester Strafford 544
39 03885 Stratham Rockingham 513
40 03858 Newton Rockingham 493
41 03873 Sandown Rockingham 476
42 03833 Exeter Rockingham 471
43 03784 West Lebanon Grafton 457
44 03870 Rye Rockingham 431
45 03431 Keene Cheshire 418
46 03106 Hooksett Merrimack 417
47 03819 Danville Rockingham 407
48 03045 Goffstown Hillsborough 392
49 03840 Greenland Rockingham 392
50 03077 Raymond Rockingham 378

Showing the top 50 of 247 ZIP codes in New Hampshire that have this figure . 03060 ranks 1st at 4,827, against 378 in 50th place.

Other rankings for New Hampshire

Cite this page

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

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