ZIP Codes of Allen County, KY

Population & People
Population & People
Total Population
20,436
Household Income
Household Income
Median Income
$62,532
Housing
Housing
Total Housing Units
8,802
Business & Economy
Business & Economy
Total Businesses
248
Employment
Employment
Employment Rate
56.01%
Education
Education
Bachelor's Degree+
18.59%
Source: U.S. Census ACS 2024 5-Year Estimates · rolled up across the 3 ZIPs in this county.
Data Last Updated: July 1, 2026
ZIP Codes:3 ZIP Codes (3 Standard, 0 PO Box, 0 Unique) [See All]
Area Codes:270 / 364
Timezone:Central (GMT -06:00)
Local Time:11:53:34 PM
Population:20,436 [See All]
FIPS:21003
CBSA:Bowling Green, KY
Land Area:314 sq mi
Water Area:8 sq mi
Coordinates:36.7089, -86.1754
Quick Link:
https://www.zip-codes.com/county/ky-allen.asp
Need Allen data in your app? Look up ZIP, county, and city data with a single API call.
Try Free
Kentucky's #53 most populous county
20,436 residents across 3 ZIPs — #53 of 120 Kentucky counties.

Standout ZIPs in this County


Most Populous
Scottsville · 17,673 people
86.5% of county total
Highest Income
Adolphus · $64,958 median
1.0× county average
Largest Land Area
Scottsville · 250.9 sq mi
Spans the most ground
Fastest Growth
Scottsville · 6.8% (10-yr)
16,549 → 17,673 residents
Most Educated
Adolphus · 26.2% bachelor's+
454 of 1,732 adults 25+

Things worth knowing about Allen County


20,436 residents live across 3 ZIPs covering 314 sq mi, served by 3 distinct USPS-recognized cities.

Population moved from 19,646 to 20,436 from 2014 to 2024 — a +4.0% change. 1 ZIPs gained residents, 2 lost.

The county's wealthiest ZIP 42120 (Adolphus, $64,958 median) and poorest ZIP 42164 (Scottsville, $60,106) are 8.3 miles apart — a 1.1× income gap across local geography.

Median home values vary 1.1× across this county — from $178,500 in 42120 (Adolphus) to $196,800 in 42164 (Scottsville).

Density varies across the county — from 63 people/sq mi in 42120 (Adolphus) to 70 in 42164 (Scottsville).

Educational attainment ranges from 17.5% bachelor's+ in 42164 (Scottsville) to 26.2% in 42120 (Adolphus) — the breadth of educational profiles across the area.

Within Kentucky, this is the #53 most populous of 120 counties and ranks #46 for median household income .

Weighted by population, the typical household earns about $60,758 across the county — reflecting what a typical resident sees, not a simple ZIP average.

18.6% of adults age 25+ hold a bachelor's degree or higher (2,632 of 14,161 reporting).

3 Standard delivery, 0 PO Box only, 0 single-entity Unique ZIPs serve this county.

Stories about Allen County


Single-ZIP anchor

One ZIP holds the majority of this county's population — a sign of a county built around a single city or town.

Scottsville

All ZIP Codes in Allen County


ZIPCityTypePopulationMedian IncomeArea (sq mi)10-yr Growth
42164ScottsvilleStandard17,673$60,106250.96.8%
42120AdolphusStandard2,745$64,95843.4-2.4%
42153HollandStandard1819.4-93.7%

Adjacent & Nearby Counties