Located in the Central (GMT -06:00) time zone. Area code 817 serves the state of Texas. This area code was assigned on January 1st, 1953. On January 1st, 1953 it went into service. 817 is a General Purpose Code. 817 service area does overlap with 682 area codes. Dialing pattern for local calls within the same NPA (area code) is 10D.