← Area code 603
603-299 phone numbers
Numbers 603-299-0000 to 603-299-9999 are assigned to New Cingular Wireless PCS, LLC in Bartlett, NH.
Not assigned to any carrier: 603-299-0xxx, 603-299-1xxx, 603-299-2xxx, 603-299-3xxx, 603-299-4xxx, 603-299-5xxx, 603-299-6xxx, 603-299-7xxx, 603-299-8xxx — calls from these use spoofed caller IDs.
Source: North American Numbering Plan Administrator, Nov 3, 2026. Numbers can move between carriers.