NPA-NXX - 631-509

This is the 631-509 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. 631
3. 631-509

The 631-509 subcode mainly covers Port Jefferson in Suffolk county. But other numbers maybe included as well.

We have a database of information derived from the public phone records of New York state. Many of the numbers in this subcode are Regular Landline registered to Cablevision Lightpath. We hear they employ a large number of people in the New York office.
Recently there have been an increase in reported calls, we've had over 1493350 comments across our systems for the 631-509 subcode.