Warren, Illinois Area Code
Warren, IL is officially utilizing an area code overlay in which area codes 779 and 815 serve the same geographic area. Ten digit dialing (area code + seven digit number) is necessary.
In addition to Warren, IL area code information read more about area codes 779 and 815 details and Illinois area codes.
Warren, IL is located in Jo Daviess County and observes the Central Time Zone.
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