San Jose-San Francisco-Oakland, CA Combined Statistical Area
The San Jose-San Francisco-Oakland, CA Combined Statistical Area is a 12-county Combined Statistical Area (CSA) designated by the United States Office of Management and Budget in Northern California that includes the San Francisco Bay Area. The CSA is more extensive than the popular local definition of the Bay Area, which consists of only the nine counties bordering San Francisco and San Pablo Bays: Alameda, Contra Costa, Marin, Napa, San Francisco, San Mateo, Santa Clara, Solano, and Sonoma.  The CSA also includes the three counties of San Joaquin, Santa Cruz, and San Benito that do not border San Francisco or San Pablo Bay, but are economically tied to the nine counties that do.
The CSA includes the vast geographic diversity of the traditional nine-county region, composed of at least six terranes (continental, seabed, or island arc fragments with distinct characteristics) pushed together over many millions of years by the forces of plate tectonics. These landscapes range from cool foggy mountains and temperate forests on the San Francisco Peninsula and Marin County, to the semi-arid, near-desert terrain in the easternmost portions of the East Bay.
San Joaquin County extends the CSA further east into the agricultural lands of the San Joaquin Valley, the southern half of the larger California Central Valley. The county includes portions of the Sacramento–San Joaquin River Delta, formed by the confluence of the Sacramento and San Joaquin rivers before they eventually flow west into the Bay Area. Several cities and communities in the county like Tracy and Mountain House have become exurbs of the Bay Area because of population growth.
Santa Cruz and San Benito counties lie to the south of the traditional nine-county region, in the northernmost part of the California Central Coast. Santa Cruz County is a strip between the Pacific coast and the crest of the Santa Cruz Mountains at the northern end of the Monterey Bay. San Benito County lies more inland along the California Coast Ranges.
|Metropolitan Statistical Areas||County(ies)||2015 Estimate||2010 Census||Change||Area (land)||Density|
|San Francisco-Oakland-Hayward MSA||Alameda, Contra Costa, San Francisco, San Mateo, and Marin||4,656,132||4,335,391||+7.40%||2,474 sq mi (6,410 km2)||1,882/sq mi (727/km2)|
|San Jose-Sunnyvale-Santa Clara MSA||Santa Clara and San Benito||1,976,836||1,836,911||+7.62%||2,679 sq mi (6,940 km2)||738/sq mi (285/km2)|
|Stockton-Lodi MSA||San Joaquin County||726,106||685,306||+5.95%||1,391 sq mi (3,600 km2)||522/sq mi (202/km2)|
|Santa Rosa MSA||Sonoma County||502,146||483,878||+3.78%||1,576 sq mi (4,080 km2)||319/sq mi (123/km2)|
|Vallejo-Fairfield MSA||Solano County||436,092||413,344||+5.50%||822 sq mi (2,130 km2)||531/sq mi (205/km2)|
|Santa Cruz-Watsonville MSA||Santa Cruz County||274,146||262,382||+4.48%||445 sq mi (1,150 km2)||616/sq mi (238/km2)|
|Napa MSA||Napa County||142,456||136,484||+4.38%||748 sq mi (1,940 km2)||190/sq mi (74/km2)|
|San Jose-San Francisco-Oakland CSA||8,713,914||8,153,696||+6.87%||10,135 sq mi (26,250 km2)||860/sq mi (332/km2)|
Economy and transportation
In 2015 the San Francisco Bay Area CSA had a GDP of $810 billion, which would rank 18th among countries. Silicon Valley, the leading high technology region in the world, is located in Santa Clara County. Major corporations in San Francisco, San Jose, Oakland, and the surrounding cities help make the region second in the nation in concentration of Fortune 500 companies, after New York. The Bay Area's northern counties encompass California's famous Wine Country, home to hundreds of vineyards and wineries. San Joaquin, Santa Cruz, and San Benito counties extend the area's agriculture and wine-producing areas.
Transportation in the San Francisco Bay Area is reliant on a complex multimodal infrastructure consisting of roads, bridges, highways, rail, tunnels, airports, and bike and pedestrian paths. The Bay Area possesses an extensive freeway and highway system. The CSA contains the three principal north-south highways in California: Interstate 5, U.S. Route 101, and California State Route 1. U.S. 101 and State Route 1 directly serve the traditional nine-county region, while Interstate 5 bypasses to the east in San Joaquin County to provide a more direct Los Angeles-to-Sacramento route. Additionally, the region is also served by several passenger rail networks such as Bay Area Rapid Transit (BART), Caltrain, the Altamont Commuter Express, and the Santa Clara Valley Transportation Authority (VTA) Light Rail.
The area is also home to several ports, including the Port of Oakland, the fifth busiest container port in the United States, and the Port of Stockton, a major inland deepwater port along the San Joaquin River. San Francisco International Airport (SFO) is the primary international airport of the region. Other airports with regular passenger service include Oakland International Airport (OAK) and San Jose International Airport (SJC), and to a lesser extent Sonoma County Airport (STS) and Stockton Metropolitan Airport (SCK).
As more people move further inland in search of larger and cheaper homes, urban planner and academic Wendell Cox wrote that the Office of Management and Budget could add Stanislaus County to the San Jose-San Francisco-Oakland CSA in the future.
- List of metropolitan areas of the United States
- List of primary statistical areas of the United States
- List of Combined Statistical Areas
- "OMB Bulletin No. 13-01: Revised Delineations of Metropolitan Statistical Areas, Micropolitan Statistical Areas, and Combined Statistical Areas, and Guidance on Uses of the Delineations of These Areas" (PDF). United States Office of Management and Budget. February 28, 2013. Retrieved April 17, 2013.
- "San Francisco Bay Area Vision Project". Focus.
- "The Association of Bay Area Governments". Association of Bay Area Governments.
- "Metropolitan and Micropolitan Statistical Area Totals Dataset: Population and Estimated Components of Change: April 1, 2010 to July 1, 2015" (CSV). 2015 Population Estimates. United States Census Bureau, Population Division. March 2016. Retrieved April 1, 2016.
- "Combined Statistical Area Totals Dataset: Population and Estimated Components of Change: April 1, 2010 to July 1, 2015" (CSV). 2015 Population Estimates. United States Census Bureau, Population Division. March 2016. Retrieved April 1, 2016.
- "GCT-PH1 – Population, Housing Units, Area, and Density: 2010 – State — Place and (in selected states) County Subdivision". 2010 United States Census. United States Census Bureau. Retrieved January 16, 2012.
- "Census 2010: Table 3A — Total Population by Race (Hispanic exclusive) and Hispanic or Latino: 2010" (Excel). California Department of Finance. Retrieved January 16, 2012.
- "Corrections to 2010 Census Population and Housing Units Counts in the State of California" (PDF). California Department of Finance. Retrieved January 16, 2012.
- "Fortune 500 2010: Annual ranking of America's largest corporations from Fortune Magazine". CNN. Retrieved August 11, 2010.
- Cox, Wendall (February 5, 2014). "The Evolving Urban Form: The San Francisco Bay Area". newgeography.com. Retrieved July 30, 2014.
It seems much growth that might have occurred in the original San Francisco metropolitan area or the later developing San Jose metropolitan area will instead occur in the Vallejo or Stockton metropolitan areas, where housing prices tend to be much lower, particularly for larger homes that are increasingly unaffordable closer to the urban core. Indeed, it is not impossible that Modesto (Stanislaus County) could be added to the San Francisco Bay CSA by 2020