← Area code 580
580-666 phone numbers
Numbers 580-666-0000 to 580-666-9999 are assigned to Southwestern Bell in Rocky, OK. 5 of its ten thousand-number blocks are assigned to other carriers (number pooling).
Not assigned to any carrier: 580-666-5xxx, 580-666-7xxx, 580-666-9xxx — calls from these use spoofed caller IDs.
Source: North American Numbering Plan Administrator, Nov 3, 2026. Numbers can move between carriers.