Prefix overview
Phone numbers in prefix 231-255
This page covers the 231-255 prefix in the United States. It shows where numbers come from, which carrier is linked to the range, and how this block is structured.
If you are looking for a specific number, you can continue to its dedicated phone page. Otherwise, this page helps you understand the broader number block behind it.
PREFIX
231-255
RATE CENTER
ONEKAMA
CARRIER
SPOK, INC.
MI
Prefix range
The prefix 231-255 includes numbers from 2312550000 to 2312559999.
This range is associated with the ONEKAMA rate center and was originally assigned to SPOK, INC..
Numbers in this prefix
20 numbers