In the United States, the Office of Management and Budget (OMB) has produced a formal definition of metropolitan areas, which are organized around county boundaries (except in New England, where cities and towns are more significant than counties as geographical and political units.) These are referred to as "Metropolitan Statistical Areas" (MSAs). If an MSA is large enough and can be subdivided into meaningful sub-metropolitan areas, then the MSA is considered a "Consolidated Metropolitan Statistical Area" (CMSA), with each subdivision called a "Primary Metropolitan Statistical Area" (PMSA). The largest MSAs in the United States are all CMSAs.

In 2003, further adjustments were made to the definition of metro areas, information about it is available on the core based statistical area entry.

The following is a list of the top metropolitan areas in the United States, according to the 2000 census:

Metropolitan Area States Type Population Other names
New York--Northern New Jersey (Jersey City, Trenton, Newark)--Long Island--Bridgeport--New Haven NY--NJ--CT--PA CMSA 21,199,865 Tri-state Area, New York area, Greater New York
Los Angeles--Riverside County--Orange County CA CMSA 16,373,645 The Southland, Southern California (The latter also refers to the entire southern portion of the state)
Chicago--Joliet--Naperville--Gary--Kenosha IL--IN--WI CMSA 9,157,540 Chicagoland, Greater Chicago, Chicagoland and Northwest Indiana (the latter refers to the eastern part extended until South Bend, Indiana)
Washington--Baltimore DC--MD--VA--WV CMSA 7,608,070 Baltimore-Washington Metropolitan Area
San Jose--San Francisco--Oakland CA CMSA 7,039,362 The Bay Area
Philadelphia--Wilmington--Atlantic City PA--NJ--DE--MD CMSA 6,188,463 The Delaware Valley
Boston--Worcester--Lawrence MA--NH--ME--CT CMSA 5,819,100 Greater Boston
Detroit--Ann Arbor--Flint MI CMSA 5,456,428 Metro Detroit
Dallas--Fort Worth--Arlington TX CMSA 5,221,801 The Metroplex
Houston--Galveston--Brazoria--Baytown--Sugar Land TX CMSA 4,669,571 Houston Metropolitan Area
Atlanta GA MSA 4,112,198 Atlanta Metropolitan Area
Miami--Ft. Lauderdale FL CMSA 3,876,380  
Seattle--Tacoma--Bremerton WA CMSA 3,554,760 Greater Puget Sound
Phoenix--Mesa AZ MSA 3,251,876 The Valley of the Sun
Minneapolis--St. Paul MN, WI MSA 2,968,806 The Twin Cities
St. Louis--East St. Louis MO, IL CMSA 2,603,607 Greater St. Louis
Pittsburgh--New Castle PA MSA 2,512,302
Cincinnati--Hamilton OH, KY, IN CMSA Greater Cincinnati/Northern Kentucky

See also Demographics of the United States, List of metropolitan areas by population, List of regions of the United States

External Resources