NPA-NXX - 509-631

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

The 509-631 subcode mainly covers Coulee Dam in Okanogan county. But other numbers maybe included as well.

We have a database of information derived from the public phone records of Washington state. Many of the numbers in this subcode are Cellular (Dedicated) registered to At&t Mobility. We hear they employ a large number of people in the Washington office.
Recently there have been an increase in reported calls, we've had over 41120 comments across our systems for the 509-631 subcode.