Every ZIP code in the United States, with weather, radar, trivia and the numbers behind it. Five digits since 1963!

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zipcodes.pro — STATE/IA/COUNTY/JEFFERSON

Jefferson County, IA ZIP codes

There are 7 ZIP codes in Jefferson County, IA, in 6 towns, from 52533 to 52635. The largest are 52556 (Fairfield), 52540 (Brighton) and 52533 (Batavia).

The county seat is Fairfield.

ZIP codes
7
Towns
6
County seat
Fairfield
County FIPS
19101
State
Iowa
Population
15,705
Median household income
$61,620
Land area
436 sq mi

Jefferson County ZIP codes by town

Fairfield (county seat)
52556, 52557

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.

Map of Jefferson County ZIP codes

52533525405255652557525675258052635

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 15,705 people live in Jefferson County, in 6,952 households, the 48th most populous of Iowa's 99 counties. The median household income is $61,620 a year, 18% below the Iowa median of $75,059 (US: $80,734). The median owner-occupied home is valued at $163,400 (21% below the Iowa median), and median gross rent is $883 a month. The median age is 43.7; 43.2% of adults 25 and over hold a bachelor's degree or higher (31.4% across Iowa); the average commute takes 16 minutes.

Population15,705Jefferson15,705
Households6,952Jefferson6,952
Median age43.7Jefferson43.7Iowa38.6US 38.9
Median household income$61,620Jefferson$61,620Iowa$75,059US $80,734
Median home value$163,400Jefferson$163,400Iowa$208,000US $332,700
Median gross rent$883Jefferson$883Iowa$972US $1,413
Bachelor's degree or higher43.2%Jefferson43.2%Iowa31.4%US 35.7%
Mean commute15.9 minJefferson15.9 minIowa19.8 minUS 26.4 min
Population density36 / sq miJefferson36 / 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
Fairfield 2 9,456
Brighton 1 588
Packwood 1 539
Batavia 1 536
Lockridge 1 452
Libertyville 1 324

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
52533 Batavia , IA Standard 1,201 $62,799 $126,800
52540 Brighton , IA Standard 1,088 $55,000 $115,300
52556 Fairfield , IA Standard 11,448 $59,243 $166,800
52557 Fairfield , IA Standard 685 — —
52567 Libertyville , IA Standard 506 $81,985 $164,100
52580 Packwood , IA Standard 711 $53,368 $116,200
52635 Lockridge , IA Standard 890 $76,250 $175,000

Cite this page

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

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