United States metropolitan area

Metropolitan Statistical Areas (MSA) are large metropolitan areas of the United States as defined by the Office of Management and Budget. These areas are urban areas with a lot of people. An earlier version of the MSA was the "Standard Metropolitan Statistical Area" (SMSA). MSAs are used for official purposes.

MSAs are made up of counties and for some county equivalents. In New England, because of the greater importance of towns over counties, similar areas are based on town units. These are called New England City and Town Areas (NECTAs).

MSAs are created around a central urban area —an areawhere there are a lot of people. The counties with the urbanized area are known as the central counties of the MSA. Other nearby counties (known as outlying counties) can be a part of the MSA if these counties have strong social and economic connections to the central counties. Some areas within these outlying counties may actually be rural areas.

The population estimates for some metro areas are not always agreed upon. In some cases, different sources give numbers of people which differ by millions. The definitions used for the last U.S. Census differed from those for previous censuses. This makes it hard to compare official information from different dates. MSA boundaries do not stretch into Canada or Mexico. This can affect the number of people in several cities. For example, Detroit, Buffalo, El Paso and San Diego are often much larger than their MSA figures.

As of June 2003, there is now an additional classification, “Metropolitan Division.” The term metropolitan division is used for a county or group of counties that are a distinct employment area within a metropolitan statistical area that has at least 2.5 million people. A metropolitan division is a part of a larger metropolitan statistical area but it is often a distinct social, economic, and cultural area within the larger region.

Top 25

The following is a list of the 25 most populated metropolitan statistical areas and metropolitan divisions in the United States, according to the July 1, 2007 U.S. Census Bureau estimates:

Rank	Metropolitan Area	Metropolitan Divisions	State(s)	Population
1	New York–Northern New Jersey–Long Island		NY–NJ–PA	18,815,988
		Edison	NJ	2,319,704
		Nassau–Suffolk	NY	2,759,762
		Newark–Union	NJ-PA	2,128,679
		New York–White Plains–Wayne	NY-NJ	11,607,843
2	Los Angeles–Long Beach–Santa Ana		CA	12,875,587
		Los Angeles–Long Beach–Glendale		9,878,554
		Santa Ana–Anaheim–Irvine		2,997,033
3	Chicago–Naperville–Joliet		IL–IN–WI	9,524,673
		Chicago–Naperville–Joliet	IL	7,952,540
		Gary	IN	698,971
		Lake County–Kenosha County	IL–WI	873,162
4	Dallas–Fort Worth–Arlington		TX	6,145,037
		Dallas–Plano–Irving		4,111,529
		Fort Worth–Arlington		2,033,508
5	Philadelphia–Camden–Wilmington		PA–NJ–DE–MD	5,827,962
		Camden	NJ	1,246,339
		Philadelphia	PA	3,887,694
		Wilmington	DE–MD–NJ	693,929
6	Houston–Sugar Land–Baytown		TX	5,628,101
7	Miami–Fort Lauderdale–Pompano Beach		FL	5,413,212
		Fort Lauderdale–Pompano Beach–Deerfield Beach		1,759,591
		Miami–Miami Beach–Kendall		2,387,170
		West Palm Beach–Boca Raton–Boynton Beach		1,266,451
8	Washington–Arlington–Alexandria		DC–VA–MD–WV	5,306,565
		Bethesda-Gaithersburg–Frederick	MD	1,155,518
		Washington–Arlington–Alexandria	DC–MD–VA–WV	4,151,047
9	Atlanta–Sandy Springs–Marietta		GA	5,278,904
10	Boston–Cambridge–Quincy		MA–NH	4,482,857
		Boston–Quincy	MA	1,858,216
		Cambridge–Newton–Framingham		1,473,416
		Peabody		733,101
		Rockingham County–Strafford County	NH	418,124
11	Detroit–Warren–Livonia		MI	4,467,592
		Detroit–Livonia–Dearborn		1,985,101
		Warren–Troy–Farmington Hills		2,482,491
12	San Francisco–Oakland–Fremont		CA	4,203,898
		Oakland–Fremont–Hayward		2,483,842
		San Francisco–San Mateo–Redwood City		1,720,056
13	Phoenix–Mesa–Scottsdale		AZ	4,179,427
14	Seattle–Tacoma–Bellevue		WA	4,109,347
		Seattle–Bellevue–Everett		2,536,182
		Tacoma		773,165
15	Riverside–San Bernardino–Ontario		CA	4,081,371
16	Minneapolis–St. Paul–Bloomington		MN–WI	3,208,212
17	San Diego–Carlsbad–San Marcos		CA	2,974,859
18	St. Louis		MO–IL	2,803,707
19	Tampa–St. Petersburg–Clearwater		FL	2,723,949
20	Baltimore–Towson		MD	2,668,056
21	Charlotte		NC	2,566,399
22	Denver–Aurora		CO	2,464,866
23	Pittsburgh		PA–WV	2,355,712
24	Portland–Vancouver–Beaverton		OR–WA	2,175,113
25	Cincinnati–Middletown		OH-KY-IN	2,133,678
26	Cleveland–Elyria–Mentor		OH	2,096,471

For all U.S. Metropolitan Statistical Areas, see the Table of United States Metropolitan Statistical Areas.

For a list including combined metropolitan areas, see the Table of United States primary census statistical areas.

United States Metropolitan Area Media

• 

  An enlargeable map of the 939 core-based statistical areas (CBSAs) of the United States and Puerto Rico as of 2020. The 384 MSAs are shown in medium green  .