Mercer County, Pennsylvania

Mercer County is a county in Pennsylvania, United States, about 15 miles northeast of
Youngstown, Ohio and 60 miles northwest of Pittsburgh. It had a population of 110,652 at the 2020
census, an estimated 109,257 by 2024, and covers 683 square miles (1,770 km2) centred near
41°19′N 80°15′W.

Mercer is the county seat; its postal code is 16137. Hermitage is the county’s largest
city. The county holds 3 cities, 13 boroughs and 20 unincorporated communities across 31
townships, plus 2 census-designated places, and it runs on Eastern Time. Its FIPS code is 42085.

Towns & Villages in Mercer County

Mercer County has 38 named places on record: 3 cities, 13 boroughs, 2 census-designated places
(CDPs) and 20 unincorporated communities with no local government of their own. In Pennsylvania,
cities and boroughs are independent municipalities, not part of any township, so most carry no
township entry below. The previous list on this page mixed genuine communities with unverified
place-name database entries, including “Five Points” repeated six times — those
have been dropped; this table keeps only places confirmed against the U.S. Census Bureau and
Wikipedia’s own community listing for the county.

Wheatland, a borough of 583 residents at the 2020 census, no longer appears on this list —
its council voted to dissolve and the borough was formally annexed into the City of Hermitage in
2024. Reynolds Heights, the county’s largest CDP, sits partly within Pymatuning Township on
the north shore of Lake Latonka; the two are separate places despite the shared shoreline.

Townships

Mercer County has 31 civil townships, most of them rural with no incorporated borough inside
their boundaries. Published 2020 census population figures are available for the following six;
the remaining twenty-five are not broken out separately in the sources checked for this page.

ZIP Codes

• 16137 — Mercer
• 16148 — Hermitage
• 16146 — Sharon
• 16121 — Farrell
• 16127 — Grove City
• 16125 — Greenville
• 16150 — Sharpsville
• 16159 — West Middlesex
• 16145 — Sandy Lake
• 16134 — Jamestown
• 16113 — Clark
• 16124 — Fredonia
• 16133 — Jackson Center
• 16151 — Sheakleyville
• 16153 — Stoneboro
• 16130 — Hadley
• 16154 — Transfer
• 16114 — Clarks Mills
• 16311 — Carlton

New Lebanon, Lake Latonka, Maysville, Milledgeville, Petersburg, Osgood, Kennard, Oniontown,
North Liberty, New Vernon, Delaware Grove and several other small unincorporated communities have
no ZIP code of their own; mail there is delivered under a neighbouring town’s code.

Geography

Mercer County sits in Pennsylvania’s northwestern corner, part of the Appalachian Plateau,
a region of rolling hills cut by streams draining toward Lake Erie and the Ohio River. Of the
county’s 683 square miles, 673 are land and 10 are water, about 1.5 percent. Shenango River
Lake, built and operated by the U.S. Army Corps of Engineers north of Hermitage, is the
county’s largest reservoir and offers camping and boating. The Shenango and Neshannock
rivers, along with French Creek, drain most of the county.

Crawford County lies to the north, Venango County to the east, Butler County to the southeast
and Lawrence County to the south, all within Pennsylvania. Mahoning County and Trumbull County,
Ohio, border the county to the west. Crawford County,
Venango County,
Butler County,
Lawrence County,
Mahoning County and
Trumbull County all border Mercer
County directly.

Demographics

Mercer County had a population of 110,652 at the 2020 census, and the latest estimate puts the
county near 109,257 residents as of 2024, a slight decline. Hermitage and Sharon are by far the
two largest communities, together holding more than a quarter of the county’s population.
Median household income runs $59,976 (2024 estimate), well below Pennsylvania’s statewide
figure of $73,824 (2023 ACS). The county’s poverty rate stands at 13.2 percent and median age
is 45.1 years, both above state averages typical of a county with a shrinking manufacturing base.

Economy & Local Life

Health care and social assistance is the county’s largest employment sector, with about
8,855 workers, followed by manufacturing at 7,467 and retail trade at 5,717. Sharon and Hermitage
carry the health care load, anchored by Sharon Regional Health System; Penn State Shenango, a
branch campus in Sharon, and Grove City College, a private liberal-arts college of about 2,400
undergraduates founded in 1876, are the county’s two four-year institutions. Sharon is the
birthplace of the Quaker Steak & Lube restaurant chain, which opened its original location
there in 1974. During the Second World War, Westinghouse Electric’s Sharon plant produced
10,000 torpedoes for the U.S. Navy. Sharon’s biggest annual event is WaterFire, a free public
art installation of roughly 80 burning braziers along the Shenango River downtown, held each
summer since 2013 and drawing crowds of about 40,000.

History

Pennsylvania created Mercer County in 1800 and organized it on November 7, 1803, carving it out
of Allegheny and Crawford counties. It was named for General Hugh Mercer, a Revolutionary War
officer who died of wounds received at the Battle of Princeton in 1777. Lawrence County was split
off from Mercer’s southern townships in 1849.

On May 31, 1985, an F5 tornado tore through Hermitage and neighboring communities, killing 18
people and injuring 310 — the strongest tornado ever recorded in Pennsylvania. The city later
built the Avenue of Flags memorial to honor those killed. Sharon’s economy, like much of the
Shenango Valley, ran on iron and steel through the twentieth century before that industry declined
in the 1970s and 1980s, a shift that still shapes the county’s employment mix today.

Getting There

Interstate 80 crosses the county’s south end, and Interstate 79 clips its southeastern
corner near Grove City; Interstate 376 runs through Hermitage and Sharon toward Youngstown. U.S.
Routes 19, 62 and 322 also cross the county, along with several state routes.

• Youngstown, Ohio — about 15 miles west
• Pittsburgh — about 60 miles southeast
• New Castle — about 20 miles south
• Meadville — about 25 miles north

Youngstown-Warren Regional Airport, about 20 miles west in Ohio, is the nearest commercial
airport. Pittsburgh International Airport, roughly 65 miles southeast, offers a larger range of
flights. Mercer County has no active Amtrak station; the nearest is in Pittsburgh.

Frequently Asked Questions

Where is Mercer County located?
It sits in Pennsylvania’s northwestern corner, about 15 miles northeast of Youngstown, Ohio,
bordered by Crawford, Venango, Butler and Lawrence counties in Pennsylvania and Mahoning and
Trumbull counties in Ohio.

What is the population of Mercer County?
110,652 at the 2020 census, with a 2024 estimate near 109,257.

How big is Mercer County?
683 square miles (1,770 km2), of which 673 square miles are land.

What is the county seat of Mercer County?
Mercer, population 1,985 at the 2020 census. Hermitage, with 16,231, is the county’s largest
city.

How many towns and cities are in Mercer County?
Three cities — Hermitage, Sharon and Farrell — plus 13 boroughs, 2 census-designated
places and 20 unincorporated communities.

What ZIP codes does Mercer County use?
16137 for Mercer, 16148 for Hermitage, 16146 for Sharon, 16121 for Farrell, and separate codes for
Grove City, Greenville, Sharpsville and the county’s smaller boroughs.

What is Mercer County known for?
The 1985 F5 tornado that struck Hermitage, Grove City College, and Sharon’s WaterFire
festival and Quaker Steak & Lube, the restaurant chain founded there in 1974.

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