Located in the Eastern (GMT -05:00) time zone. Area code 223 serves the state of Pennsylvania. This area code was assigned on October 28th, 2016. On September 26th, 2017 it went into service. 223 is a General Purpose Code. 223 service area does overlap with 717 area codes. Dialing pattern for local calls within the same NPA (area code) is 10D. All calls within and between the 717 and 223 NPAs can be dialed as 10D or 1+10D. Calls to other NPAs must be dialed as 1+10D.