The Philadelphia metropolitan area, also referred to as the Delaware Valley or Greater Philadelphia, is a major metropolitan area in the Northeastern United States that centers on Philadelphia, the sixth-most populous city in the United States. The region spans up to four states: southeastern Pennsylvania, southern New Jersey, northern Delaware, and the northern Eastern Shore of Maryland, though it is sometimes considered a tri-state region if northeastern Maryland is excluded. With a core metropolitan statistical area population of 6.245 million residents and a combined statistical area population of 7.379 million as of the 2020 census, it is the ninth-largest metropolitan statistical area in the United States in 2024 and the 68th-largest metropolitan region in the world.

In addition to Philadelphia, other major population centers in the Philadelphia metro area include Reading, Upper Darby Township, and Chester in Pennsylvania; Atlantic City, Camden, Vineland, and Cherry Hill in South Jersey; and Wilmington and Dover in Delaware. As of 2023, the Philadelphia metro area's gross domestic product (GDP) exceeds US$557 billion, making it the nation's 11th-largest metropolitan economy. in reference to its role as the revolutionary capital during the colonial era in which the Second Continental Congress gathered at Independence Hall and unanimously adopted the Declaration of Independence, authorized the formation of the Continental Army, and appointed George Washington its commander to resist the British. After the Continental Army's victory, Philadelphia served as the nation's first capital for most of the 18th century until 1800, when construction of Washington, D.C. was completed. The U.S. Constitution, the world's longest-standing body of federal law, was ratified at Independence Hall in Philadelphia in 1789.

The metro area is one of the nation's leading regions for academia and academic research with a considerable number of globally-known and highly ranked universities, including the University of Pennsylvania, one of the nation's eight Ivy League universities. Other major universities and colleges in the region include Swarthmore College, Drexel University, La Salle University, Bryn Mawr College, Rowan University, Rutgers University–Camden, Saint Joseph's University, Stockton University, Temple University, Thomas Jefferson University, the University of Delaware, Villanova University, West Chester University, Widener University, Ursinus College, Haverford College, the Pennsylvania Academy of the Fine Arts, the Moore College of Art and Design, the Tyler School of Art and Architecture, and others.

The Philadelphia metropolitan area is considered a biotechnology hub, and has garnered the nickname "Cellicon Valley" for its central role in the development of immunotherapies to treat different cancers. As of 2025, the area ranks as one of the Big Five U.S. venture capital hubs, facilitated by its proximity to both New York City's entrepreneurial and financial ecosystems and to the federal regulatory environment of Washington, D.C. Elsewhere in the metropolitan area, South Jersey has emerged as an East Coast epicenter for logistics and major warehouses.

Culturally, the region is home to the dialect known as Philadelphia English, shares a unique cuisine known as Philadelphia cuisine, has played a formidable role in popular music, and is known for having one of the nation's most passionate and devoted sports cultures centered around its five professional sports teams.

Geography and population

thumb|The drainage basin of the [[Delaware River]]

The Philadelphia metropolitan area is geographically associated and proximate to the Delaware River and its three primary tributaries, the Schuylkill River, Lehigh River, and Brandywine Creek.

U.S. government agencies have reached various definitions of metropolitan Philadelphia. The Office of Management and Budget (OMB) defines metropolitan statistical area (MSAs), which are regions with relatively high population densities at their cores and close economic ties throughout their respective areas. MSAs are further combined into combined statistical areas (CSAs), reflecting commuting patterns. Neither is a formal administrative division.

Metropolitan statistical area (MSA)

As of the 2020 U.S. census, the Philadelphia–Camden–Wilmington metropolitan statistical area is the seventh-largest MSA in the nation with 6,245,051 people. The MSA includes:

  • Camden, NJ Metropolitan Division
  • Burlington County, NJ
  • Camden County, NJ
  • Gloucester County, NJ
  • Philadelphia, PA Metropolitan Division
  • Bucks County, PA
  • Chester County, PA
  • Delaware County, PA
  • Montgomery County, PA
  • Philadelphia City, PA
  • Wilmington, DE-MD-NJ Metropolitan Division
  • Cecil County, MD
  • New Castle County, DE
  • Salem County, NJ

{| class="wikitable sortable"

!County

!2021 estimate

!2020 census

!Change

!Area

!Density

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|Philadelphia City, PA

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|Montgomery County, PA

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|Bucks County, PA

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|Delaware County, PA

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|New Castle County, DE

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|Chester County, PA

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|Camden County, NJ

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|Burlington County, NJ

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|Gloucester County, NJ

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|Cecil County, MD

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|Salem County, NJ

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|- class="sortbottom" style="background:#fbfbbb"

|Philadelphia MSA

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thumb|Population density in the Philadelphia urban area

Combined statistical area (CSA)

As of 2020, the Philadelphia–Reading–Camden, PA-NJ-DE-MD CSA is the nation's ninth-largest combined statistical area with a population of 7,379,700. Philadelphia-Reading-Camden Combined Statistical Area includes:

  • Philadelphia-Camden-Wilmington MSA (11 counties, as defined above)
  • Berks County, Pennsylvania, comprising the Reading, PA MSA
  • Atlantic County, New Jersey, comprising the Atlantic City-Hammonton, NJ MSA
  • Cape May County, New Jersey, comprising the Ocean City, NJ MSA
  • Cumberland County, New Jersey, comprising the Vineland-Bridgeton, NJ MSA
  • Kent County, Delaware, comprising the Dover, DE MSA

{| class="wikitable sortable"

!County

!2021 estimate

!2020 census

!Change

!Area

!Density

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|Philadelphia MSA

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|Berks County, PA

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|Atlantic County, NJ

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|Kent County, DE

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|Cumberland County, NJ

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|Cape May County, NJ

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|- class="sortbottom" style="background:#fbfbbb"

|Philadelphia CSA

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|}thumb|The Philadelphia metropolitan area is part of the [[Northeast megalopolis, the second-most highly populated megaregion of the U.S. with 52.3 million residents.]]

Statistical history

When metropolitan areas were originally defined in 1950, most of this urban area was split between four metropolitan areas, or standard metropolitan areas, as they were then called. The Philadelphia SMA included Philadelphia, Bucks, Chester, Delaware, and Montgomery counties in Pennsylvania, and Burlington, Camden, and Gloucester counties in South Jersey. The Wilmington SMA included New Castle County in Delaware and Salem County in South Jersey. Berks County was designated as the Reading SMA and Atlantic County, New Jersey was the Atlantic City SMA.

In 1960, Cecil County, Maryland was added to what was now the Wilmington Standard Metropolitan Statistical Area (SMSA). In 1980, Cumberland County, New Jersey was defined as the Vineland-Millville-Bridgeton SMSA.

In 1990, the Philadelphia, Wilmington and Vineland-Millville-Bridgeton SMSAs were merged with the Trenton SMSA to form the Philadelphia–Wilmington–Trenton Consolidated Metropolitan Statistical Area. At the same time, Cape May County, New Jersey was added to the Atlantic City SMSA. The "Philadelphia-Wilmington-Trenton" became obsolete one census later when Trenton, New Jersey was moved to the New York-Newark-Bridgeport CSA. The Philadelphia-Wilmington-Vineland CSA included the Philadelphia-Wilmington-Camden MSA and the Vineland-Millville-Bridgeton MSA.

In 2000, Kent County, Delaware was designated the Dover MSA, and Kent County and Atlantic City were added to the Philadelphia CSA in 2010. As a result of new 2010 definitions, based on a threshold of 15% labor interchange between MSAs, two additional MSAs were added, Ocean City, New Jersey and Reading, Pennsylvania. The CSA to which they belong is known as Philadelphia-Reading-Camden.

Climate Types

All of it is Humid Subtropical<gallery>

File:Köppen Climate Types Maryland.png|Maryland Köppen Climate Types

File:Köppen Climate Types Pennsylvania.png|Pennsylvania Köppen Climate Types

File:Köppen Climate Types Delaware.png|Delaware Köppen Climate Types

File:Köppen Climate Types New Jersey.png|New Jersey Köppen Climate Types

</gallery>

Subregions

The Philadelphia–Reading–Camden combined statistical area includes sixteen counties in four states. The five Pennsylvania counties in the metropolitan statistical area are collectively known as Southeastern Pennsylvania. In addition to Philadelphia, major municipalities in Southeastern Pennsylvania include the inner suburbs of Upper Darby Township and Bensalem Township. Berks County, which forms its own MSA and contains the CSA's second largest city, Reading, is occasionally not considered to be part of Southeastern Pennsylvania and is sometimes assigned to South Central Pennsylvania.

The seven New Jersey counties in the CSA are in South Jersey. Atlantic County, Cape May County, and Cumberland County each form their own respective metropolitan statistical areas. Atlantic City, Cape May County, New Jersey, and the southern Jersey Shore, including Margate City, Ventnor City, the Wildwoods, Northfield, Sea Isle City, are major tourist destinations for people from inside and outside of the metropolitan area. Other major municipalities in South Jersey include Cherry Hill and Camden, which is across the Delaware River, east of Philadelphia. Burlington, Camden, Gloucester, and Salem Counties comprise the Delaware River Region, one of seven officially recognized tourism regions by the New Jersey Department of Tourism.

The two counties of Delaware in the CSA constitute a majority of Delaware's land mass and population. Wilmington is the most populous city in Delaware and the fifth-most populous municipality in the metropolitan Philadelphia. The lone Maryland county in the Philadelphia-Reading-Camden Combined Statistical Area is part of the region known as the Eastern Shore of Maryland.

Ethnically, Indians make up the largest foreign-born population in Greater Philadelphia.

Largest municipalities

thumb|[[Philadelphia, the most populous city in the metropolitan area and the sixth-most populous city in the nation with over 1.6 million residents]]

thumb|[[Reading, Pennsylvania]]

thumb|[[Ocean City, New Jersey]]

thumb|[[Wilmington, Delaware]]

The following municipalities are all within the Philadelphia–Reading–Camden combined statistical area as of the 2020 census:

{| class="wikitable sortable"

|-

! City

! Pop.

! County

! State

|-

| Philadelphia

| 1,603,797

| Philadelphia

| PA

|-

| Reading

| 95,112

| Berks

| PA

|-

| Upper Darby Township

| 85,681

| Delaware

| PA

|-

| Cherry Hill

| 74,553

| Camden

| NJ

|-

| Camden

| 71,792

| Camden

| NJ

|-

| Wilmington

| 70,898

| New Castle

| DE

|-

| Gloucester Township

| 66,034

| Camden

| NJ

|-

| Lower Merion Township

| 63,633

| Montgomery

| PA

|-

| Bensalem Township

| 62,707

| Bucks

| PA

|-

| Vineland

| 60,780

| Cumberland

| NJ

|-

| Abington Township

| 58,502

| Montgomery

| PA

|-

| Bristol Township

| 54,291

| Bucks

| PA

|-

| Haverford Township

| 50,437

| Delaware

| PA

|-

| Washington Township

| 48,667

| Gloucester

| NJ

|-

| Egg Harbor Township

| 47,842

| Atlantic

| NJ

|-

| Evesham Township

| 46,826

| Burlington

| NJ

|-

| Middletown Township

| 46,040

| Bucks

| PA

|-

| Mount Laurel

| 44,633

| Burlington

| NJ

|-

| Northampton Township

| 39,915

| Bucks

| PA

|-

| Winslow Township

| 39,907

| Camden

| NJ

|}

Climate

The Philadelphia metro area has four distinct seasons with ample precipitation and is divided by the 0&nbsp;°C (32&nbsp;°F) January isotherm. Philadelphia and the New Jersey portion of the area, almost all of the Delaware and Maryland portions, most of Delaware County and lower Bucks County, lowland southern Chester County, and some southern and lowland areas of Montgomery County have a humid subtropical climate (Cfa according to the Köppen climate classification.) The remainder of the metro area has a hot summer humid continental climate (Dfa.) PRISM Climate Group at Oregon State University

Snow amounts may vary widely year-to-year and normally do vary widely within metro Philadelphia. The region has two ski resorts, Bear Creek Mountain Resort in Longswamp Township, Berks County and Spring Mountain Adventures in central Montgomery County.

Using the -3&nbsp;°C January isotherm as a boundary, all of the metro area is humid subtropical. The hardiness zone in the region ranges from 6b in higher areas of Berks and northern Bucks Counties to 8a in Atlantic City and Cape May. [https://planthardiness.ars.usda.gov/]

Using the Trewartha climate classification system, which requires eight months to average at least 50&nbsp;°F for the climate to be considered subtropical, the region only has seven such months, so the area considered Cfa by Köppen is oceanic (Do) in the Trewartha system.