231-400 phone numbers

Numbers 231-400-0000 to 231-400-9999 are assigned to Onvoy, Llcv in Alanson, MI. 2 of its ten thousand-number blocks are assigned to other carriers (number pooling).

Not assigned to any carrier: 231-400-7xxx — calls from these use spoofed caller IDs.

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

Reported numbers in 231-400