← Area code 307
307-423 phone numbers
Numbers 307-423-0000 to 307-423-9999 are assigned to Bandwidth.com CLEC, LLC in Buffalo, WY. 5 of its ten thousand-number blocks are assigned to other carriers (number pooling).
Not assigned to any carrier: 307-423-3xxx, 307-423-4xxx, 307-423-5xxx, 307-423-6xxx — calls from these use spoofed caller IDs.
Source: North American Numbering Plan Administrator, Nov 3, 2026. Numbers can move between carriers.