Establish a local presence by purchasing a phone number in area code 312. Phone numbers in area code 312 are associated with the state of Illinois. There are currently at least 1 U.S. cities and 45 U.S. ZIP Codes associated with this telephone area code. In addition, there are at least 800 NXX's (the three-digit code that makes up digits 4-6 of a standard 10-digit U.S. phone number) available for use along with area code 312.
Phone numbers in area code 312 are associated with the state of Illinois.
The 312 area code currently has at least 1 cities in Illinois associated with it: and West Chicago, IL.
There are at least 45 U.S. ZIP codes associated with the area code 312 at this time (view all here).
The ZIP Code 60629 is the ZIP Code most frequently connected to the 312 area code. The 60629 ZIP Code is primarily associated with Cook County in the state of Illinois.
There are 3 counties associated with the 312 area code: Cook County; Lake County; DuPage County.
An NXX, which is also known as the a "central office code" or an "exchange", is the three-digit sequence that comprises digits 4-6 of a standard 10-digit U.S. phone number. The NXX is the second main part of a phone number that comes directly after the area code, e.g. (312)-588-xxxx.
Detailed information about area code 312 phone numbers. Establish a Illinois presence with a 312 number.