ZIP Codes of Union County, PA

Population & People
Population & People
Total Population
39,903
Household Income
Household Income
Median Income
$74,967
Housing
Housing
Total Housing Units
16,373
Business & Economy
Business & Economy
Total Businesses
942
Employment
Employment
Employment Rate
53.72%
Education
Education
Bachelor's Degree+
29.97%
Source: U.S. Census ACS 2024 5-Year Estimates · rolled up across the 12 ZIPs in this county.
Data Last Updated: June 1, 2026
ZIP Codes:12 ZIP Codes (7 Standard, 5 PO Box, 0 Unique) [See All]
Area Codes:272 / 570
Timezone:Eastern (GMT -05:00)
Local Time:2:13:33 PM
Population:39,903 [See All]
FIPS:42119
CBSA:Lewisburg, PA
Land Area:303 sq mi
Water Area:2 sq mi
Coordinates:40.9417, -77.0480
Quick Link:
https://www.zip-codes.com/county/pa-union.asp
Need Union data in your app? Look up ZIP, county, and city data with a single API call.
Try Free
Pennsylvania's shortest commutes
18-minute avg commute — the shortest in the state.
Wide geographic spread
ZIPs range from 98.2 sq mi down to 1.40 — a 70× sprawl ratio.

Standout ZIPs in this County


Most Populous
Lewisburg · 18,403 people
46.1% of county total
Highest Income
New Columbia · $91,661 median
1.2× county average
Largest Land Area
Mifflinburg · 98.2 sq mi
Spans the most ground
Fastest Growth
Winfield · 13.6% (10-yr)
2,676 → 3,039 residents
Most Educated
Lewisburg · 39.4% bachelor's+
4,442 of 11,286 adults 25+

Things worth knowing about Union County


39,903 residents live across 12 ZIPs covering 303 sq mi, served by 12 distinct USPS-recognized cities.

Population moved from 41,328 to 39,903 from 2014 to 2024 — a -3.4% change. 5 ZIPs gained residents, 7 lost.

The county's wealthiest ZIP 17856 (New Columbia, $91,661 median) and poorest ZIP 17886 (West Milton, $47,574) are 5.6 miles apart — a 1.9× income gap across local geography.

Median home values vary 2.1× across this county — from $137,500 in 17829 (Hartleton) to $288,900 in 17889 (Winfield).

Density varies 23× across the county — from 25 people/sq mi in 17845 (Millmont) to 575 in 17886 (West Milton).

Educational attainment ranges from 5.5% bachelor's+ in 17887 (White Deer ) to 39.4% in 17837 (Lewisburg) — the breadth of educational profiles across the area.

Within Pennsylvania, this is the #53 most populous of 67 counties and ranks #23 for median household income .

Weighted by population, the typical household earns about $81,600 across the county — reflecting what a typical resident sees, not a simple ZIP average.

30.0% of adults age 25+ hold a bachelor's degree or higher (7,889 of 26,323 reporting).

7 Standard delivery, 5 PO Box only, 0 single-entity Unique ZIPs serve this county.

All ZIP Codes in Union County


ZIPCityTypePopulationMedian IncomeArea (sq mi)10-yr Growth
17837LewisburgStandard18,403$88,97556.4-9.6%
17844MifflinburgStandard10,291$68,31498.23.0%
17856New ColumbiaStandard3,167$91,66138.4-7.4%
17889WinfieldStandard3,039$89,06324.813.6%
17845MillmontStandard2,058$66,51081.6-3.6%
17855New BerlinStandard1,014$88,9292.0-0.1%
17886West MiltonStandard804$47,5741.49.1%
17887White DeerPO Box5910.097.0%
17829HartletonPO Box212$80,4170.0-5.8%
17885WeikertPO Box181$92,9170.01.7%
17835LaureltonPO Box114$48,6110.0-49.6%
17880SwengelPO Box29$61,6670.0-54.7%

Adjacent & Nearby Counties