NPA-NXX - 309-523

This is the 309-523 subcode (NPA-NXX) prefix page. Follow a prefix to find the number you are looking for. We divide our pages up to make them more user friendly to navigate!

1. Area Codes
2. 309
3. 309-523

The 309-523 subcode mainly covers Port Byron in Rock Island county. But other numbers maybe included as well.

We have a database of information derived from the public phone records of Illinois state. Many of the numbers in this subcode are Regular Landline registered to Frontier. We hear they employ a large number of people in the Illinois office.
Recently there have been an increase in reported calls, we've had over 147546 comments across our systems for the 309-523 subcode.