Located in the Atlantic (GMT -04:00) time zone. Area code 787 serves the state of Puerto Rico. This area code was assigned on December 31st, 1969. On March 1st, 1996 it went into service. 787 is a General Purpose Code. 787 service area does overlap with 939 area codes. Dialing pattern for local calls within the same NPA (area code) is 10D.