← Area code 620
620-710 phone numbers
Numbers 620-710-0000 to 620-710-9999 are assigned to Southwestern Bell in Sedan, KS. 6 of its ten thousand-number blocks are assigned to other carriers (number pooling).
Not assigned to any carrier: 620-710-3xxx, 620-710-4xxx, 620-710-6xxx — calls from these use spoofed caller IDs.
Source: North American Numbering Plan Administrator, Nov 3, 2026. Numbers can move between carriers.