| Area Code | 309 |
| State | Illinois |
| Current Time in Area Code 309 | 309> CDT |
| Timezone | Central Daylight Time |
| Regional Market Area | Davenport-Rock Island-Moline Area Peoria-Bloomington Area Quincy-Hannibal-Keokuk |
| Metro Area(s) | Bloomington, IL Davenport-Moline-Rock Island, IA-IL Galesburg, IL Macomb, IL Peoria, IL |
| Population (2020) | 896513 |
| Adjacent Area Codes | 217,319,447,563,779,815 |
| Bloomington |
| Galesburg |
| Moline |
| Normal |
| Pekin |
| Peoria |
| Rock Island |