Area Code 331 Illinois, USA

WhereCall is here to provide you with the most information on the area code 331, located in Illinois, USA. This area code contains 108 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)331
LocationIllinois, USA
In Jeopardy?No
Is Assigned?Yes
Assignment Date23 Jul 1999
In Service?Yes
In Service Date07 Oct 2007
Parent NPA630
OverlayYes
Overlay Complex331/630
Predominant Timezone(s)UTC-06:00
Reverse Phone Lookup »
331 area code map