Lehigh County, Pennsylvania

Lehigh County is a county in Pennsylvania, United States, in the Lehigh Valley about 55 miles
north of Philadelphia. It had a population of 374,557 at the 2020 census, an estimated 384,383 by
2024, and covers 345 square miles (890 km2) centred near 40°37′N 75°35′W.

Allentown is the county seat and the state’s third-largest city; its postal code is 18101. The
county holds 2 cities, 8 boroughs and 26 unincorporated and census-designated communities across
15 townships, and it runs on Eastern Time. Its FIPS code is 42077.

Towns & Villages in Lehigh County

Lehigh County has two cities, eight boroughs and a long list of smaller CDPs and unincorporated
communities layered across its 15 townships. CDP stands for census designated place, a Census
Bureau-defined cluster with no local government of its own; Unincorp. covers crossroads and rural
communities with no formal boundary.

Coplay, Cementon, Egypt, Fullerton, Hokendauqua and Stiles all share Whitehall Township’s 18052
ZIP block along the Lehigh River — treat them as one postal cluster, not five separate
towns, when mailing anything. Bethlehem straddles the Lehigh–Northampton county line; only
its western edge lies in Lehigh County, and the city’s government and downtown sit in Northampton
County.

Townships

The five smallest townships — Lynn, Washington, Weisenberg, Heidelberg, Lower Milford,
Lowhill and Hanover — have not published a separate 2020 township population count in the
sources checked for this page; their 2010 counts ran from roughly 1,600 (Hanover) to 4,200
(Lynn).

ZIP Codes

• 18101–18109 — Allentown (multiple ZIPs cover different sections of the city)
• 18049 — Emmaus (also serves rural Upper Milford Township)
• 18032 — Catasauqua
• 18037 — Coplay and Cementon
• 18052 — Whitehall, Egypt, Fullerton, Hokendauqua, Stiles and West Catasauqua
• 18062 — Macungie
• 18011 — Alburtis
• 18036 — Coopersburg
• 18080 — Slatington
• 18015 — Fountain Hill and the Lehigh County edge of Bethlehem
• 18106 — Wescosville
• 18031 — Breinigsville
• 18078 — Schnecksville
• 18087 — Trexlertown and Germansville
• 18066 — New Tripoli
• 18069 — Orefield
• 18065 — Neffs
• 18034 — Center Valley
• 18051 — Fogelsville
• 18092 — Zionsville
• 18059 — Laurys Station

Ancient Oaks, Dorneyville, Cetronia, DeSales University and Slatedale have no ZIP of their own
— they sit inside larger rural-route delivery areas and mail addresses to the nearest post
office town instead.

Geography

Lehigh County sits in the Lehigh Valley, the industrial corridor carved by the Lehigh River as
it flows southeast toward the Delaware River. The Blue Mountain ridge forms the county’s northern
edge in Heidelberg, Lynn and Washington townships; south of it the land opens into rolling
farmland and the suburban belt around Allentown. Water covers 3.1 square miles (8.0 km2) of the
county, mostly the Lehigh River and its Little Lehigh and Jordan creek tributaries.

Lehigh County borders six other Pennsylvania counties: Carbon County to the north
(Carbon County),
Northampton County to the northeast
(Northampton County),
Bucks County to the southeast
(Bucks County), Montgomery County to the
south (Montgomery
County), Berks County to the west
(Berks County) and Schuylkill County to
the northwest (Schuylkill County).

Demographics

Lehigh County had 374,557 residents at the 2020 census, up from 349,497 in 2010; the 2024
estimate is 384,383. Allentown (125,845) and Bethlehem’s Lehigh County slice anchor the
population, followed by Lower Macungie Township (32,426) and Whitehall Township (29,173) as the
two largest township-only communities. Median household income in the county was $80,079 in 2024
(Data USA), above Pennsylvania’s statewide median of $73,824 (2023 ACS). Population density works
out to roughly 1,090 people per square mile of land.

Economy & Local Life

Health care and social assistance is the county’s largest employment sector at about 32,900
workers, followed by manufacturing (26,300) and retail trade (21,100), per Data USA employment
figures. Air Products and Chemicals, a Fortune 500 industrial gas company, is headquartered in
Trexlertown in Upper Macungie Township. PPL Corporation, the region’s electric utility, is
headquartered in Allentown. Mack Trucks built its name in Allentown for over a century before
relocating its headquarters out of state in 2009, and the city’s silk-mill trade once employed
more than 10,000 people across 85 mills in the 1940s. The Great Allentown Fair, first held in
1852, runs every Labor Day week at the county fairgrounds.

History

Lehigh County was organized on March 6, 1812, when the Pennsylvania legislature split it off
from Northampton County. It takes its name from the Lehigh River, itself from the Lenape word
Lechauweki, meaning “where there are forks.” European settlement began around 1730. In 1777,
after the Battle of Brandywine, Continental Congress officials hid the Liberty Bell in Zion Reformed
Church in Allentown to keep it from British forces occupying Philadelphia. The opening of the
Lehigh Canal in 1827 gave the county’s iron and coal trade a route to Philadelphia markets and
turned Allentown and its neighboring boroughs into a 19th- and 20th-century manufacturing center.

Getting There

Interstate 78 crosses the county east–west and Interstate 476, the Pennsylvania Turnpike’s
Northeast Extension, crosses it north–south; US Routes 22 and 222 and Pennsylvania Routes 29,
100, 309 and 378 fill in the rest of the network.

• Philadelphia — 55 miles south
• Reading — 30 miles southwest
• Scranton — 60 miles north
• New York City — 85 miles east

Lehigh Valley International Airport, in Hanover Township just north of Allentown, is
Pennsylvania’s fourth-busiest airport and the closest commercial airport for the whole county.
Lehigh County has no Amtrak station; the nearest regular passenger rail service is at Philadelphia
30th Street Station, with Trans-Bridge and other bus lines connecting Allentown to New York City
in the meantime.

Frequently Asked Questions

Where is Lehigh County, Pennsylvania?
Lehigh County is in eastern Pennsylvania’s Lehigh Valley, about 55 miles north of Philadelphia.

What is the population of Lehigh County?
Lehigh County had a population of 374,557 at the 2020 census, estimated at 384,383 by 2024.

How big is Lehigh County?
Lehigh County covers 345 square miles (890 km2) of land plus 3.1 square miles (8.0 km2) of water.

What is the county seat of Lehigh County?
Allentown is the county seat and Pennsylvania’s third-largest city.

How many towns are in Lehigh County?
Lehigh County has 2 cities, 8 boroughs and more than 20 additional CDPs and unincorporated
communities spread across its 15 townships.

What ZIP codes cover Lehigh County?
Allentown uses ZIPs 18101 through 18109; the rest of the county’s boroughs and villages each carry
their own ZIP, from 18011 (Alburtis) to 18092 (Zionsville) — see the ZIP Codes section above.

Does Lehigh County have Amtrak service?
No. The county has no passenger rail station; Lehigh Valley International Airport in Hanover
Township is the region’s main transportation hub instead.

More counties in this state: Towns and villages in Pennsylvania.