← Area code 351
351-243 phone numbers
Numbers 351-243-0000 to 351-243-9999 are assigned to AT&T - Local (rate centre WESTFORD, MA, NANPA abbreviation). 3 of its ten thousand-number blocks are assigned to other carriers (number pooling).
Not assigned to any carrier: 351-243-2xxx, 351-243-3xxx, 351-243-4xxx, 351-243-5xxx, 351-243-6xxx, 351-243-7xxx — calls from these use spoofed caller IDs.
Source: North American Numbering Plan Administrator, Nov 3, 2026. Numbers can move between carriers.