← Area code 660
660-274 phone numbers
Numbers 660-274-0000 to 660-274-9999 are assigned to Level 3 Communications, LLC in King City, MO. 2 of its ten thousand-number blocks are assigned to other carriers (number pooling).
Not assigned to any carrier: 660-274-0xxx, 660-274-2xxx, 660-274-3xxx, 660-274-4xxx, 660-274-5xxx, 660-274-6xxx, 660-274-8xxx, 660-274-9xxx — calls from these use spoofed caller IDs.
Source: North American Numbering Plan Administrator, Nov 3, 2026. Numbers can move between carriers.