313-203 phone numbers

Numbers 313-203-0000 to 313-203-9999 are assigned to Teleport Communications America, LLC (rate centre DETROITZN6, MI, NANPA abbreviation). 2 of its ten thousand-number blocks are assigned to other carriers (number pooling).

Source: North American Numbering Plan Administrator, Nov 3, 2026. Numbers can move between carriers.

Reported numbers in 313-203