Delaware County, Pennsylvania

Delaware County is a county in Pennsylvania, United States, about 12 miles southwest of
Philadelphia. It had a population of 576,830 at the 2020 census, an estimated 580,937 by 2024, and
covers 191 square miles (490 km2), of which 184 square miles (480 km2) are land, centred near
39°55′N 75°24′W.

Media is the county seat; its postal code is 19063. The county holds 1 city, 27 boroughs and 21
townships — 49 municipalities in all, since Pennsylvania has no unincorporated land —
and it runs on Eastern Time. Its FIPS code is 42045.

Towns & Villages in Delaware County

Every square mile of Delaware County sits inside one of its 49 incorporated municipalities: 1
city, 27 boroughs and 21 townships, all with equal legal standing. Many well-known local names
— Havertown, Wayne, Broomall — are not separate municipalities at all but postal or
historic communities inside a township; those are listed further down. The table below covers all
49 official municipalities.

Three places in the county share the name Chester: the city of Chester, the separate Chester
Township that borders it, and Chester Heights borough farther northwest — all distinct
municipalities. Darby works the same way: Darby borough and Darby Township are adjoining but
separately governed. Neither pair should be read as one place.

Beyond the 49 municipalities, a number of well-known local names are unincorporated communities
inside a township rather than towns in their own right. The Census Bureau tabulates population for
only a few of these as separate places; the rest have no population count of their own.

Townships

Delaware County’s 21 townships range from Upper Darby, the county’s most populous municipality
of any kind, to Chadds Ford, a small rural township on the Chester County line. Sorted by
population, largest first:

ZIP Codes

• 19013 — Chester (city)
• 19063 — Media (also serves 19065 and 19091, Media PO box ZIPs)
• 19082 — Upper Darby and Millbourne
• 19083 — Havertown
• 19026 — Drexel Hill
• 19050 — Lansdowne, East Lansdowne and Yeadon
• 19023 — Darby, Collingdale and Colwyn
• 19064 — Springfield
• 19018 — Clifton Heights and Aldan
• 19073 — Newtown Square
• 19010 — Bryn Mawr
• 19008 — Broomall
• 19061 — Marcus Hook
• 19015 — Brookhaven
• 19036 — Glenolden
• 19086 — Wallingford
• 19078 — Ridley Park
• 19081 — Swarthmore
• 19079 — Sharon Hill
• 19032 — Folcroft
• 19076 — Prospect Park
• 19070 — Morton and Rutledge
• 19074 — Norwood
• 19317 — Chadds Ford
• 19028 — Edgmont
• 19017 — Chester Heights
• 19087 — Wayne

Several boroughs and townships have no ZIP of their own and are served under a neighbouring
town’s code: Parkside, Rose Valley, Trainer and Upland among the boroughs, and most of the
county’s 21 townships, since a Pennsylvania township is a unit of government rather than a postal
delivery area. That is why the Townships table above lists settlement names instead of ZIPs for
most rows.

Geography

Delaware County occupies Pennsylvania’s southeastern corner along the Delaware River, in the
low, gently rolling Piedmont country between the Appalachian foothills and the coastal plain. Of
its 191 square miles, 184 are land and 6.8 are water, about 3.5 percent — mostly the
Delaware River itself, which forms the county’s entire eastern and southern boundary. Ridley
Creek and Crum Creek, both tributaries of the Delaware, run through the county’s middle and give
their names to Ridley Creek State Park in Upper Providence and Edgmont townships. Marcus Hook, on
the river’s edge, sits at Pennsylvania’s lowest point.

Montgomery County lies to the north, Philadelphia County to the northeast, Gloucester County,
New Jersey, across the Delaware River to the southeast, New Castle County, Delaware, to the
southwest, and Chester County to the west. Montgomery
County, Philadelphia
County, Gloucester County and
New Castle County all have posts on
this site; Chester County — whose own seat, West Chester, is a different place from
Delaware County’s West-Chester-adjacent Chadds Ford — does not yet.

Demographics

Delaware County had a population of 576,830 at the 2020 census, the fifth-largest of
Pennsylvania’s 67 counties, and an estimated 580,937 by 2024. Upper Darby Township, at 85,681, and
Haverford Township, at 50,431, are the two largest municipalities; Chester, the only city, ranks
third at 32,605. Median household income is $89,546 (2024 estimate, Data USA), well above
Pennsylvania’s statewide figure of $73,824 (2023 ACS). Population density works out to roughly
3,130 people per square mile of land, among the densest counties in the state outside Philadelphia
itself, reflecting the county’s position as one of Philadelphia’s original inner-ring suburbs.

Economy & Local Life

Health care and social assistance employs the most county residents, about 52,307 workers,
ahead of educational services at 32,058 and retail trade at 28,982. Crozer Health runs several of
the county’s hospitals. Higher education is a major presence: Villanova University in Radnor
Township, Swarthmore College in Swarthmore borough, Haverford College in Haverford Township and
Widener University in Chester together enroll tens of thousands of students. Boeing’s rotorcraft
plant in Ridley Township builds Chinook and Osprey helicopters and is one of the county’s largest
manufacturing employers. Chester itself hosts Subaru Park, home of Major League Soccer’s
Philadelphia Union, and Harrah’s Philadelphia Casino and Racetrack, both major draws along the
riverfront.

History

Delaware County was formed on 26 September 1789 from part of Chester County and named for the
Delaware River. Chester, within its borders, is Pennsylvania’s oldest city — settled by
Swedish colonists in 1644 and the site of William Penn’s first landing in the colony in 1682.
Chester’s Delaware River Iron Ship Building and Engine Works produced the first steel ships built
for the U.S. Navy, and its Sun Shipyard was the largest single shipyard in the world during the
Second World War. Deindustrialization hit the city hard after the 1960s: Chester was declared a
financially distressed municipality in 1995 and filed for municipal bankruptcy in 2022.

Media became the county seat in 1851, taking the role from Chester, and was laid out on four
farms totaling 480 acres near the county’s geographic center — the likely source of its
name. In June 2006, Media became the first town in the United States certified as a Fair Trade
Town.

Getting There

Interstate 95 runs the length of the county’s eastern edge along the Delaware River through
Chester, Ridley and Tinicum townships. Interstate 476, the Mid-County Expressway known locally as
the Blue Route, crosses north–south through Haverford, Marple, Springfield and Radnor. US
1, US 30 and US 322 also cross the county, along with PA 3, PA 252 and PA 320.

• Philadelphia — about 12 miles northeast
• Wilmington, Delaware — about 17 miles south
• West Chester — about 12 miles northwest
• Chester — within the county, on the river

Philadelphia International Airport sits partly within Tinicum Township, giving the county a
major commercial airport inside its own borders. Amtrak’s Northeast Corridor trains stop at
Philadelphia’s 30th Street Station, about 15 miles northeast of Media, and at Wilmington Station
to the south.

Frequently Asked Questions

Where is Delaware County located?
It sits in Pennsylvania’s southeastern corner along the Delaware River, about 12 miles southwest
of Philadelphia, bordered by Montgomery, Philadelphia and Chester counties in Pennsylvania, New
Castle County in Delaware, and Gloucester County across the river in New Jersey.

What is the population of Delaware County?
576,830 at the 2020 census, with a 2024 estimate near 580,937.

How big is Delaware County?
191 square miles (490 km2) total, of which 184 square miles are land.

What is the county seat of Delaware County?
Media, county seat since 1851, though Chester — the county’s only city — is its
largest municipality.

How many towns and municipalities are in Delaware County?
49: 1 city, 27 boroughs and 21 townships, since Pennsylvania has no unincorporated county land.

What ZIP codes does Delaware County use?
More than two dozen, from 19008 (Broomall) and 19013 (Chester) to 19342 (Glen Mills) and 19373
(Thornton); Media’s is 19063.

What is Delaware County known for?
Chester’s shipbuilding history and 2022 municipal bankruptcy, Media’s 2006 Fair Trade Town
certification, and a cluster of colleges — Villanova, Swarthmore and Haverford —
inside its borders.

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