Published: October 03, 2013
The Houston area in Texas is currently served by 3 area codes: 713, 281 and 832. All 3 codes cover the same geographic area. A 4th area code will be activated on July 1, 2014 as a relief method for the aforementioned 3 area code overlay complex.
See official NANPA announcement featuring implementation dates and other info (PDF document).
Visit area code 346 page for a list of cities served, map and other info.