← Area code 423
423-684 phone numbers
Numbers 423-684-0000 to 423-684-9999 are assigned to Bandwidth.com CLEC, LLC in Kingsport, TN.
Not assigned to any carrier: 423-684-3xxx, 423-684-4xxx, 423-684-5xxx, 423-684-6xxx, 423-684-7xxx, 423-684-8xxx, 423-684-9xxx — calls from these use spoofed caller IDs.
Source: North American Numbering Plan Administrator, Nov 3, 2026. Numbers can move between carriers.