Area Code 312 Illinois, USA

WhereCall is here to provide you with the most information on the area code 312, located in Illinois, USA. This area code contains 747 prefixes and is not in jeopardy of exceeding the known supply of central office codes during the planning/implementation interval for relief.


NPA Information
Area Code (NPA) 312
NPA Status Active
Location Illinois, USA
In Jeopardy? No
Is Assigned? Yes
Assignment Date 01 Jan 1947
In Service? Yes
In Service Date 01 Jan 1947
Overlay Yes
Overlay Complex 312/872
Predominant Timezone(s) UTC-06:00
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