Other cities in the 312 area code include: Clarendon Hills, North Chicago, Oak Brook, Streamwood, Hinsdale, Northbrook, Rolling Meadows, and Chicago.
Chicago, officially the City of Chicago, is the third-most populous city in the United States. With over 2.7 million residents, it is the most populous city in the state of Illinois, and the Midwestern United States. It is the county seat of Cook County. The Chicago metropolitan area, often referred to as Chicagoland, has nearly 10 million people and is the third-largest in the U.S. Chicago is called the architecture capital of the United States. In terms of wealth and economy, Chicago is considered one of the most important business centers in the world. Chicago was incorporated as a city in 1837, near a portage between the Great Lakes and the Mississippi River watershed, and grew rapidly in the mid-nineteenth century.
Evanston is a city in Cook County, Illinois, United States, 12 miles (19 km) north of downtown Chicago, bordered by Chicago to the south, Skokie to the west, and Wilmette to the north, with a population of 74,486 as of 2010 . It is one of the North Shore communities that adjoin Lake Michigan and is the home of Northwestern University. The boundaries of the city of Evanston are coterminous with those of the former Evanston Township, which was dissolved in 2014 by voters with its functions being absorbed by the city of Evanston.
Oak Park is a village adjacent to the West Side of the city of Chicago in Cook County, Illinois, United States. It is the 29th largest municipality in Illinois as measured by population in the 2010 US Census, and has easy access to downtown Chicago (the Chicago Loop) via public transportation including the CTA Blue and Green lines, buses, and Metra commuter rail. Pace buses serve the Village for travel within its borders and connecting to neighboring suburbs. As of the 2010 United States Census the Village had a total population of 51,878. Oak Park was settled beginning in the 1830s, with rapid growth later in the 19th century and early 20th century. It incorporated in 1902, breaking off from Cicero.
The 312 area code lies within the Central Daylight Time Zone (or CDT). The current time in CDT is 4:27 AM on Jul 07, 2020.