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 — STATE/WI/COUNTY/JEFFERSON

Jefferson County, WI ZIP codes

There are 10 ZIP codes in Jefferson County, WI, in 10 towns, from 53036 to 53594. The largest are 53538 (Fort Atkinson), 53094 (Watertown) and 53549 (Jefferson). 1 more crosses into it from a neighbouring county: 53190.

The county seat is Jefferson.

ZIP codes
10
Partly in it
1 more
Towns
10
County seat
Jefferson
County FIPS
55055
Population
86,003
Median household income
$83,750
Land area
556 sq mi
Area code
262

Jefferson County ZIP codes by town

Jefferson (county seat)
53549

Each ZIP code is listed under the county most of its land lies in and the town the Postal Service names it for; a ZIP code's own page shows exactly how it is split.

ZIP codes partly in Jefferson County

This ZIP code lies mostly in a neighbouring county but covers a twentieth or more of Jefferson County.

Map of Jefferson County ZIP codes

53036530385309453137531565317853538535495355153594

The ZIP codes of Jefferson County, shaded. Outlines are Census ZIP Code Tabulation Areas (2020), which approximate the mail routes; PO-box and single-address codes have no area and are not drawn. Click any area to open its ZIP code.

Jefferson County in numbers

About 86,003 people live in Jefferson County, in 34,873 households, the 20th most populous of Wisconsin's 72 counties. The median household income is $83,750 a year, 8% above the Wisconsin median of $77,485 (US: $80,734). The median owner-occupied home is valued at $274,100 (about the same as the Wisconsin median), and median gross rent is $1,035 a month. The median age is 41.5; 28.5% of adults 25 and over hold a bachelor's degree or higher (33.4% across Wisconsin); the average commute takes 25 minutes.

Population86,003Jefferson86,003
Households34,873Jefferson34,873
Median age41.5Jefferson41.5Wisconsin40.2US 38.9
Median household income$83,750Jefferson$83,750Wisconsin$77,485US $80,734
Median home value$274,100Jefferson$274,100Wisconsin$266,500US $332,700
Median gross rent$1,035Jefferson$1,035Wisconsin$1,087US $1,413
Bachelor's degree or higher28.5%Jefferson28.5%Wisconsin33.4%US 35.7%
Mean commute24.8 minJefferson24.8 minWisconsin22.2 minUS 26.4 min
Population density155 / sq miJefferson155 / sq mi

U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates. Survey estimates carry margins of error, wider for small places. Sources and methods.

Largest towns in Jefferson County

Largest towns in Jefferson County
TownZIP codesPopulation
Watertown 1 22,774
Fort Atkinson 1 12,463
Jefferson 1 7,732
Lake Mills 1 6,470
Waterloo 1 3,600
Johnson Creek 1 3,362
Ixonia 1 2,684
Palmyra 1 2,195
Sullivan 1 663
Helenville 1 96

Population of the census place of that name where there is one, otherwise of the ZIP codes the Postal Service addresses by it. A town's ZIP codes can reach past the county line.

Neighbouring counties

Counties that share a ZIP code with Jefferson County.

Not sure you are in Jefferson County? What county am I in? answers from your location, near a county line included.

Every ZIP code in Jefferson County, with figures

ZIP codes in Jefferson County
ZIP City Type Population Median income Median home
53036 Ixonia , WI Standard 3,730 $92,674 $352,300
53038 Johnson Creek , WI Standard 4,192 $96,127 $327,400
53094 Watertown , WI Standard 17,998 $73,443 $237,500
53137 Helenville , WI Standard 1,650 $116,550 $366,200
53156 Palmyra , WI Standard 3,232 $85,313 $238,200
53178 Sullivan , WI Standard 2,497 $99,875 $371,500
53538 Fort Atkinson , WI Standard 18,813 $82,783 $245,900
53549 Jefferson , WI Standard 9,873 $80,101 $262,200
53551 Lake Mills , WI Standard 9,731 $94,401 $357,400
53594 Waterloo , WI Standard 5,199 $88,390 $244,200

Cite this page

zipcodes.pro. “Jefferson County ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/state/wi/county/jefferson

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