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Crystal Lake, IL Area Codes
Crystal Lake, Illinois (population 42,288) uses area codes 815 and 779.
Carriers with Crystal Lake numbers
21 prefixes are assigned to the Crystal Lake exchange: 0% mobile, 48% VoIP and cable, 52% landline.
| Carrier | Prefixes |
|---|---|
| AT&T (Illinois Bell) | 7 |
| Metropcs | 2 |
| AT&T (Teleport) | 2 |
| Lumen (Level 3) | 2 |
| Onvoy (Sinch) | 2 |
| Spok | 1 |
| Verizon Business (MCImetro) | 1 |
| Comcast (Xfinity) | 1 |
Area codes used in Crystal Lake
| Area code | Prefixes serving Crystal Lake | Main carriers in this code |
|---|---|---|
| 815 | 16 | Frontier, AT&T (Illinois Bell), Lumen (Level 3) |
| 779 | 5 | Onvoy (Sinch), AT&T Mobility, Stratus Networks |
Crystal Lake phone number prefixes
Numbers starting with these first six digits were originally assigned to the Crystal Lake exchange.
815-204Spok815-219Metropcs815-261Verizon Business (MCImetro)815-276AT&T (Teleport)815-301Lumen (Level 3)815-356AT&T (Illinois Bell)815-404Metropcs815-425Lumen (Level 3)815-444AT&T (Illinois Bell)815-455AT&T (Illinois Bell)815-459AT&T (Illinois Bell)815-477AT&T (Illinois Bell)815-479AT&T (Illinois Bell)815-526AT&T (Teleport)815-788AT&T (Illinois Bell)815-893Comcast (Xfinity)779-220Bandwidth779-356Fractel779-388Onvoy (Sinch)779-800Onvoy (Sinch)779-994Peerless Network
Nearby cities in area code 815
- Joliet
- Rockford
- Plainfield
- DeKalb
- McHenry
- New Lenox
- Lockport
- Woodstock
- Belvidere
- Homer Glen
- Loves Park
- Kankakee
Questions
- What is the area code for Crystal Lake, IL?
- Crystal Lake uses 2 area codes: 815 and 779. They overlay each other, so all of them cover the whole city and you dial 10 digits for local calls.
- What time zone is Crystal Lake in?
- Crystal Lake is in the Central time zone.