---
title: "Area code 309: Illinois, United States"
url: "https://lookvalid.com/area-code/309.md"
canonical_url: "https://lookvalid.com/area-code/309"
last_updated: "2026-10-23"
type: "reference"
summary: "Area code 309 serves Illinois, United States. Number formats, numbering rules, a live phone validator and the other codes in Illinois."
---

# Area code 309: Illinois, United States

Area code 309 serves Illinois, United States. Number formats, numbering rules, a live phone validator and the other codes in Illinois.

NANPA lists 780 central office codes (prefixes) in use in area code 309, held by 69 holders across 171 rate centers.
Frontier North holds the most prefixes, 99 (13%). 73% of the prefixes are pooled, which means their thousands-blocks can belong to different companies.
The FCC unwanted-call data has 1,628 complaints on file for 1,308 numbers in 309, most often filed as "Unwanted Calls". These are consumer reports, not findings.

## Facts

- In service since: 1957-01-01
- Time zone: Central (C)
- Assigned overlays: 861 (2023-02-24)
- Prefixes in use: 780
- Pooled prefixes: 569 (73%)
- Rate centers: 171
- Companies holding prefixes: 69
- Assignment dates on file: 2001-01-12 to 2026-06-24 (333 prefixes)
- ZIP codes in its places: 179

## Rate centers

| Rate center | Prefixes | Share |
| --- | --- | --- |
| PEORIA | 155 | 20% |
| BLOOMINGTN | 76 | 10% |
| ROCKISLAND | 41 | 5% |
| MACOMB | 23 | 3% |
| GALESBURG | 20 | 3% |
| MOLINE | 17 | 2% |
| PEKIN | 17 | 2% |
| EASTMOLINE | 16 | 2% |
| 163 other rate centers | 415 | 53% |

## Carriers

| Holder | Prefixes | Share |
| --- | --- | --- |
| Frontier North | 99 | 13% |
| Illinois Bell Tel | 83 | 11% |
| Onvoy | 73 | 9% |
| Level 3 Communications | 66 | 8% |
| Verizon Wireless | 46 | 6% |
| Mediacom Telephony Of Illinois | 39 | 5% |
| 63 other carriers | 374 | 48% |

A prefix holder is the company a code was assigned to, not necessarily a number's current carrier, because numbers can be ported to another company.

## History

- 1957-01-01: Area code 309 went into service.
- 2023-02-24: Area code 861 went into service as an overlay in the same area as 309.

## Nearest area codes

The area codes closest to 309, measured between the centers of the ZIP code places they serve, are 447 (about 74 miles), 217 (about 75 miles), 815 (about 78 miles), 779 (about 82 miles) and 331 (about 110 miles).

## ZIP codes

179 ZIP codes fall in places that have a rate center in this area code. The places with the most are Peoria, IL (29 ZIP codes), Pekin, IL (3 ZIP codes) and Rock Island, IL (3 ZIP codes). A ZIP code and an area code are unrelated systems, so a ZIP code can sit in more than one area code and an area code spans many ZIP codes.

## Complaints on file

1,628 complaints for 1,308 numbers. Numbers whose latest complaint falls in each year:

- 2023: 87
- 2024: 72
- 2025: 70

## Questions

### Where is area code 309?

NANPA assigns area code 309 to Illinois, United States.

### In which state does area code 309 sit?

Illinois. 309 is one of 17 area codes the NANPA table assigns to the state.

### Which places does area code 309 cover?

The places with the most ZIP codes among the rate centers in 309 are Peoria, IL, Pekin, IL and Rock Island, IL. The rate center list on this page shows all of them.

### Who owns area code 309?

NANPA assigns area codes. Within 309, Frontier North holds the most prefixes, 99 prefixes or 13%.

### Which time zone does 309 use?

The NANPA NPA report lists the time zone for 309 as Central (C).

### What year did 309 enter service?

The NANPA NPA report gives an in-service date of 1957-01-01, so 309 has been in use since 1957.

### Does area code 309 have an overlay?

Yes. 861 (in service 2023-02-24) shares the same area with 309, so numbers from all of them are local to each other.

### Which area codes are nearest to 309?

The area codes closest to 309, measured between the centers of the ZIP code places they serve, are 447 (about 74 miles), 217 (about 75 miles), 815 (about 78 miles), 779 (about 82 miles) and 331 (about 110 miles).

### How many prefixes does area code 309 have?

NANPA's report dated 2026-10-17 lists 780 prefixes in service in 309, spread over 171 rate centers and 69 holders.

### Are there complaints about 309 numbers?

The FCC data on file has 1,628 complaints for 1,308 numbers in 309. They are unverified consumer reports. A number with no complaints on file is not proven safe.

Sources: NANPA central office code report dated 2026-10-17; NANPA NPA report dated 2026-10-18; FCC unwanted-call complaints, data fetched 2026-10-17; ZIP code places from GeoNames (CC BY 4.0).