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/WA/OLDEST

ZIP Codes With the Oldest Population in Washington

What this measures. Median age of residents, ACS 5-year estimate. Source: Census American Community Survey, data release 2026-10-12.

# ZIP City County Median age
1 98558 Mckenna Pierce 91.7
2 99136 Hay Whitman 82.2
3 98536 Copalis Crossing Grays Harbor 75.0
4 98644 Seaview Pacific 72.3
5 98581 Ryderwood Cowlitz 72.1
6 99146 Laurier Ferry 70.3
7 99131 Gifford Stevens 70.1
8 98286 Shaw Island San Juan 69.4
9 98832 Marlin Grant 68.5
10 99401 Anatone Asotin 67.9
11 98297 Waldron San Juan 67.8
12 98555 Lilliwaup Mason 67.2
13 98050 Preston King 66.5
14 98253 Greenbank Island 66.3
15 98340 Hansville Kitsap 66.2
16 99147 Lincoln Lincoln 66.2
17 98616 Cougar Skamania 66.0
18 98852 Stehekin Chelan 65.6
19 98365 Port Ludlow Jefferson 65.1
20 98575 Quinault Grays Harbor 65.0
21 98819 Conconully Okanogan 64.8
22 99150 Malo Ferry 64.8
23 98592 Union Mason 64.7
24 98569 Ocean Shores Grays Harbor 63.7
25 98361 Packwood Lewis 63.5
26 98260 Langley Island 63.3
27 98640 Ocean Park Pacific 63.1
28 99181 Valley Stevens 62.8
29 98320 Brinnon Jefferson 62.7
30 98358 Nordland Jefferson 62.5
31 98647 Skamokawa Wahkiakum 62.4
32 99180 Usk Pend Oreille 62.3
33 98261 Lopez Island San Juan 62.2
34 98547 Grayland Pacific 62.2
35 98280 Orcas San Juan 61.9
36 98376 Quilcene Jefferson 61.8
37 98382 Sequim Clallam 61.8
38 98303 Anderson Island Pierce 61.6
39 98257 La Conner Skagit 61.5
40 98834 Methow Okanogan 61.5
41 98602 Appleton Klickitat 61.2
42 98239 Coupeville Island 61.1
43 98262 Lummi Island Whatcom 61.1
44 98814 Carlton Okanogan 61.1
45 98833 Mazama Okanogan 61.0
46 99105 Benge Adams 60.8
47 98224 Baring King 60.5
48 98641 Oysterville Pacific 60.4
49 98827 Loomis Okanogan 60.4
50 98267 Marblemount Skagit 60.1

Showing the top 50 of 590 ZIP codes in Washington that have this figure . 98558 ranks 1st at 91.7, against 60.1 in 50th place.

Other rankings for Washington

Cite this page

zipcodes.pro. “ZIP Codes With the Oldest Population in Washington.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/rankings/wa/oldest

Underlying data is public domain or openly licensed — sources, vintages and licences.