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zipcodes.pro — STATE/KY/COUNTY/SIMPSON

Simpson County, KY ZIP codes

Simpson County, KY has 2 ZIP codes: 42134 and 42135. 2 more cross into it from neighbouring counties: 42206 and 42170.

The county seat is Franklin.

ZIP codes
2
Partly in it
2 more
Towns
1
County seat
Franklin
County FIPS
21213
Population
19,972
Median household income
$59,858
Land area
234 sq mi
Metro area
Franklin

Simpson County ZIP codes by town

Franklin (county seat)
42134, 42135

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 Simpson County

These ZIP codes lie mostly in a neighbouring county but each cover a twentieth or more of Simpson County.

Map of Simpson County ZIP codes

4213442135

The ZIP codes of Simpson 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.

Simpson County in numbers

About 19,972 people live in Simpson County, in 8,025 households, the 58th most populous of Kentucky's 120 counties. The median household income is $59,858 a year, 6% below the Kentucky median of $63,726 (US: $80,734). The median owner-occupied home is valued at $229,400 (12% above the Kentucky median), and median gross rent is $1,012 a month. The median age is 38.8; 18.8% of adults 25 and over hold a bachelor's degree or higher (27.6% across Kentucky); the average commute takes 21 minutes.

Population19,972Simpson19,972
Households8,025Simpson8,025
Median age38.8Simpson38.8Kentucky39.1US 38.9
Median household income$59,858Simpson$59,858Kentucky$63,726US $80,734
Median home value$229,400Simpson$229,400Kentucky$205,600US $332,700
Median gross rent$1,012Simpson$1,012Kentucky$967US $1,413
Bachelor's degree or higher18.8%Simpson18.8%Kentucky27.6%US 35.7%
Mean commute21.0 minSimpson21.0 minKentucky24.0 minUS 26.4 min
Population density85 / sq miSimpson85 / 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.

Neighbouring counties

Counties that share a ZIP code with Simpson County.

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

Every ZIP code in Simpson County, with figures

ZIP codes in Simpson County
ZIP City Type Population Median income Median home
42134 Franklin , KY Standard 19,380 $59,113 $226,800
42135 Franklin , KY No street area — — —

Cite this page

zipcodes.pro. “Simpson County ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/state/ky/county/simpson

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