Crystal Lake, Illinois Area Code
Crystal Lake, IL is currently using 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 Crystal Lake, IL area code information read more about area codes 779 and 815 details and Illinois area codes.
Crystal Lake, IL is located in McHenry County and observes the Central Time Zone.
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