231-681 phone numbers

Numbers 231-681-0000 to 231-681-9999 are assigned to Frontier North, Inc. in Fruitport, MI. 8 of its ten thousand-number blocks are assigned to other carriers (number pooling).

Not assigned to any carrier: 231-681-9xxx — calls from these use spoofed caller IDs.

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

Reported numbers in 231-681