| General Information about Area Code 815 | |
|---|---|
| Country | United States |
| State / Province / Territory | Illinois |
| Major City | Rockford |
| Time Zone | Central (UTC-06:00) |
| Prefix | Primary City | County | Phone Type |
|---|---|---|---|
| 815-693 | Joliet | Will | Wireless |
| 815-289 | Rockford | Winnebago | Wireless |
| 815-259 | Thomson | Carroll | Landline |
| 815-578 | Mchenry | Mchenry | Landline |
| 815-395 | Rockford | Winnebago | Landline |
| 815-571 | Shannon | Carroll | Landline |
| 815-270 | Lanark | Carroll | Landline |
| 815-389 | South Beloit | Winnebago | Landline |
| 815-781 | Chebanse | Iroquois | Landline |
| 815-744 | Joliet | Will | Landline |
| 815-785 | Watseka | Iroquois | Landline |
| 815-422 | Saint Anne | Kankakee | Landline |
| 815-567 | Dwight | Livingston | Landline |
| 815-689 | Cullom | Livingston | Landline |
| 815-298 | Rockford | Winnebago | Wireless |
| 815-854 | Long Point | Livingston | Landline |
| 815-651 | Joliet | Will | Landline |
| 815-829 | Chadwick | Carroll | Landline |
| 815-812 | Dakota | Stephenson | Landline |
| 815-943 | Harvard | Mchenry | Landline |