| 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 |
|---|---|---|---|
| 815-531 | Joliet | Will | Landline |
| 815-260 | Joliet | Will | Wireless |
| 815-956 | Morrison | Whiteside | Landline |
| 815-799 | Rock Falls | Whiteside | Landline |
| 815-589 | Fulton | Whiteside | Landline |
| 815-264 | Waterman | Dekalb | Landline |
| 815-665 | Ottawa | La Salle | Landline |
| 815-994 | Dixon | Lee | Wireless |
| 815-971 | Rockford | Winnebago | Landline |
| 815-341 | Joliet | Will | Wireless |
| 815-641 | Rockford | Winnebago | Wireless |
| 815-986 | Rockford | Winnebago | Wireless |
| 815-870 | Rockford | Winnebago | Wireless |
| 815-805 | Durand | Winnebago | Landline |
| 815-282 | Loves Park | Winnebago | Landline |
| 815-543 | Rockford | Winnebago | Wireless |
| 815-787 | Dekalb | Dekalb | Landline |
| 815-804 | Pecatonica | Winnebago | Landline |
| 815-583 | Morrison | Whiteside | Landline |
| 815-454 | Sheffield | Bureau | Landline |