Located in the Eastern (GMT -05:00) time zone. Area code 610 serves the state of Pennsylvania. This area code was assigned on January 5th, 1993. On January 8th, 1994 it went into service. 610 is a General Purpose Code. 610 service area does overlap with 484 area codes. Dialing pattern for local calls within the same NPA (area code) is 10D. All calls within and between the 215 and 267 and 484 and 610 NPAs can be dialed as 10D or 1+10D. Calls to other NPAs must be dialed as 1+10D.