NPA-NXX - 310-400

This is the 310-400 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. 310
3. 310-400

The 310-400 subcode mainly covers Compton in Los Angeles county. But other numbers maybe included as well.

We have a database of information derived from the public phone records of California state. Many of the numbers in this subcode are Cellular (Dedicated) registered to T-mobile. We hear they employ a large number of people in the California office.
Recently there have been an increase in reported calls, we've had over 9818605 comments across our systems for the 310-400 subcode.