← Area code 660
660-431 phone numbers
Numbers 660-431-0000 to 660-431-9999 are assigned to Level 3 Communications, LLC in Smithton, MO.
Not assigned to any carrier: 660-431-0xxx, 660-431-1xxx, 660-431-2xxx, 660-431-3xxx, 660-431-5xxx, 660-431-6xxx, 660-431-7xxx, 660-431-8xxx, 660-431-9xxx — calls from these use spoofed caller IDs.
Source: North American Numbering Plan Administrator, Nov 3, 2026. Numbers can move between carriers.