Crystal Lake, Illinois
Central Time Zone (UTC-6) · IL · —
About Area Codes in Crystal Lake, Illinois
Crystal Lake, Illinois is served by 2 area codes: 815, 779. When multiple area codes serve the same geographic area, it typically indicates overlay codes have been added to accommodate growing demand for phone numbers. All local calls within Crystal Lake require 10-digit dialing. The city is in the Central time zone (UTC-6).
Frequently Asked Questions
What area code is Crystal Lake, Illinois?
Crystal Lake, Illinois uses area codes 815 and 779.
What time zone is Crystal Lake in?
Crystal Lake is in the Central time zone (UTC-6).
Do I need to dial 10 digits when calling Crystal Lake?
Yes, all local calls in Crystal Lake require 10-digit dialing because the area is served by multiple overlay area codes.
When was area code 815 created?
Area code 815 is one of the original 86 area codes established in 1947 as part of the North American Numbering Plan (NANP).
What cities share area code 815 with Crystal Lake?
Other cities sharing area code 815 with Crystal Lake include Belvidere, Bolingbrook, Channahon, DeKalb, Freeport, among others.
Crystal Lake, IL · Central Time Zone