← Area code 580
580-635 phone numbers
Numbers 580-635-0000 to 580-635-9999 are assigned to Level 3 Communications, LLC in Hillsdale, OK. 1 of its ten thousand-number blocks are assigned to other carriers (number pooling).
Not assigned to any carrier: 580-635-1xxx, 580-635-2xxx, 580-635-4xxx, 580-635-5xxx, 580-635-6xxx, 580-635-7xxx, 580-635-8xxx, 580-635-9xxx — calls from these use spoofed caller IDs.
Source: North American Numbering Plan Administrator, Nov 3, 2026. Numbers can move between carriers.