Trenton, NJ is currently using one area code which is area code 609. Area code 609 was created from a split of area code 201 and put into service on January 1, 1957.
In addition to Trenton, NJ area code 609 serves central and southeastern New Jersey including the larger cities and communities of Atlantic City, Ewing, Trenton and Willingboro in addition to many smaller communities within the area code 609 service area.
Trenton, NJ is located in Mercer County and observes the Eastern Time Zone. View our Times by Area Code tool.