Fairfield County is the southwestern-most and most densely populated county of the U.S. state of Connecticut. As of the 2010 census, the county's population was 916,829, estimated to have increased to 939,904 in 2013. The county contains four of the state's largest cities (Bridgeport (1st), Stamford (3rd), Norwalk (6th) and Danbury (7th)) whose combined population of 433,368 is almost half the county's.
The United States Office of Management and Budget has designated Fairfield County as the Bridgeport-Stamford-Norwalk, CT Metropolitan Statistical Area. The United States Census Bureau ranked the Bridgeport-Stamford-Norwalk, CT Metropolitan Statistical Area as the 57th most populous metropolitan statistical area of the United States as of July 1, 2012. The Office of Management and Budget has further designated the Bridgeport-Stamford-Norwalk, CT Metropolitan Statistical Area as a component of the more extensive New York-Newark, NY-NJ-CT-PA Combined Statistical Area, the most populous combined statistical area and primary statistical area of the United States as of July 1, 2012.
Fairfield County's Gold Coast helped rank it sixth in the US in per-capita personal income by the Bureau of Economic Analysis in 2005, contributing substantially to Connecticut being one of the most affluent states in the US. In addition to its wealthy communities, Fairfield County is also home to lower-middle and working class-cities. Other communities are more densely populated and economically diverse than the affluent areas for which the county is better known.
As is the case with all eight of Connecticut's counties, there is no county government and no county seat. As an area it is only a geographical point of reference. In Connecticut the cities and towns are responsible for all local governmental activities including fire and rescue, schools, and snow removal; in a few cases, neighboring towns will share certain resources.