ROUND LAKE — IL
Data last updated: June 25, 2026
Area Codes
Top Carriers
| Carrier | OCN | NXX Count |
|---|---|---|
| T-MOBILE USA, INC. | 6529 | 6 |
| ILLINOIS BELL TEL CO | 9329 | 3 |
| COMCAST IP PHONE, LLC | 318J | 2 |
| LEVEL 3 COMMUNICATIONS, LLC - IL | 6115 | 2 |
| MCIMETRO ACCESS TRANSMISSION SERVICES LLC - IL | 7196 | 2 |