NPA-NXX - 509-540

This is the 509-540 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. 509-540

The 509-540 subcode mainly covers Walla Walla in Walla Walla 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 Verizon Wireless. 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 58781 comments across our systems for the 509-540 subcode.