231-538 phone numbers

Numbers 231-538-0000 to 231-538-9999 are assigned to 123.net, LLC in Fremont, MI. 8 of its ten thousand-number blocks are assigned to other carriers (number pooling).

Not assigned to any carrier: 231-538-9xxx — calls from these use spoofed caller IDs.

Source: North American Numbering Plan Administrator, Nov 3, 2026. Numbers can move between carriers.

Reported numbers in 231-538