Implementation details of the new area code were announced in NANPA Planning Letter #375 in March 2008. Permissive ten-digit local dialing of numbers in the existing 304 area code began no later than July 26, 2008. During this period, local 304 calls could still be dialed with just seven digits.
Implementation details of the new area code were announced in NANPA Planning Letter #375 in March 2008.  The permissive ten-digit local dialing of numbers within the existing 304 area code began no later than July 26, 2008. During this period, local 304 calls could still be dialed with just seven digits.