ZIP codes

ZIP codes in Winnebago County, Wisconsin

Winnebago County has 18 ZIP codes. 9 lie entirely inside it and 9 are shared with neighboring counties, so part of their land and their people are elsewhere. About 169,985 people live in the parts inside it (ACS 2020–2024).

By the All Map Tools Team

ZIP codes: 18; With 1% or more of their land inside
Entirely inside: 9; 99% or more of their land
Shared with other counties: 9; Most with Outagamie County (4)
Most populated ZIP: 54956; 46,567 people · Neenah
Least populated ZIP: 54980; 218 people · Waukau
Largest ZIP by land: 54904; 78 sq mi · Oshkosh

Map of the ZIP codes in Winnebago County

Entirely in the county (99% or more of its land)
Shared, mostly in this county
Shared, mostly in other counties
Neighboring counties

Open in the interactive tool

Each area is a ZIP code with its number where it fits. Hover over one to see its name.

All ZIP codes in Winnebago County

18 ZIP codes in Winnebago County, WI, by number
ZIP code	Main city	Population	Land in the county	Residents in the county
54901	Oshkosh	37,294	100%	37,294
54902	Oshkosh	22,243	100%	22,243
54904	Oshkosh	22,273	99.4%	≈ 22,255
54914	Appleton	31,849	3.8%	≈ 771
54915	Appleton	44,367	5.8%	≈ 3,146
54923	Berlin	8,793	8.4%	≈ 357
54927	Butte des Morts	540	100%	540
54940	Fremont	4,533	30%	≈ 1,173
54947	Winchester	2,323	100%	2,323
54952	Harrison	27,312	23%	≈ 18,782
54956	Neenah	46,567	96%	≈ 46,308
54963	Omro	7,271	99.6%	≈ 7,255
54964	Waukau	974	72%	≈ 762
54971	Ripon	10,907	20%	≈ 744
54979	Van Dyne	2,037	4.3%	≈ 180
54980	Waukau	218	100%	218
54985	Oshkosh	249	100%	249
54986	Winneconne	5,394	99.1%	≈ 5,385

ZIP codes shared with other counties

These 9 ZIP codes have part of their land in another county. The first figure is the share of their land in Winnebago County; then, where the rest lies.

54914 (Appleton): 3.8% here; 96% in Outagamie County.
54915 (Appleton): 5.8% here; 50% in Calumet County and 44% in Outagamie County.
54923 (Berlin): 8.4% here; 48% in Waushara County and 43% in Green Lake County.
54940 (Fremont): 30% here; 31% in Waushara County, 30% in Waupaca County, and 9.9% in Outagamie County.
54952 (Harrison): 23% here; 77% in Calumet County.
54956 (Neenah): 96% here; 3.5% in Outagamie County.
54964 (Waukau): 72% here; 28% in Fond du Lac County.
54971 (Ripon): 20% here; 59% in Fond du Lac County and 21% in Green Lake County.
54979 (Van Dyne): 4.3% here; 96% in Fond du Lac County.

Cities and prefixes

By main city (the city, town or CDP each ZIP shares the most land with), the ones with the most are Oshkosh (4), Appleton (2), Waukau (2), Berlin (1), Butte des Morts (1), and Fremont (1); 13 places in all.

All 18 start with the same three digits, 549: the prefix of the USPS sorting center that handles them.

Neighboring counties

Each one with its ZIP codes. Those without a page of their own open in the tool.

Tools for this county

ZIP codes by county or city The same ZIP codes on an interactive map, with the list as CSV or to copy County map with cities Its cities, towns and CDPs with their population ZIP codes in a radius The ZIP codes within 10 miles of its center, or any distance you like

Sources

U.S. Census Bureau, 2020 ZCTA to County, ZCTA to Place and ZCTA to Census Tract Relationship Files (and the 2022 County Subdivision to ZCTA file for Connecticut). Public domain.
U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates, table B01003 (population of each ZIP code, census tract and Connecticut town). Public domain.
U.S. Census Bureau, Vintage 2025 Population Estimates (county population) and 2025 Gazetteer Files (land area and interior point of each ZIP code). Public domain.
U.S. Census Bureau, Cartographic Boundary Files: ZCTAs 2020 and counties 2025, 1:500,000; county adjacency file 2025. Public domain.

How we count. ZIP codes here are the Census Bureau’s ZIP Code Tabulation Areas (ZCTAs), the areas it draws to match USPS ZIP codes; ZIPs with no area of their own (PO boxes, single buildings) aren’t included. A ZIP can cross county lines: “Land in the county” is the exact share of its land inside, from the Census relationship files. “Residents in the county” is the whole ZIP for those entirely inside; for shared ones it’s an estimate, spreading the people of each census tract over the land it shares with the ZIP. Population: ACS 2020–2024. Methodology.

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