Trenton, NJ Area Codes

Area codes serving Trenton

Trenton sits in New Jersey, part of the Northeast region and the Eastern Time zone. Its numbers are spread across an overlay of 2 codes that all cover the same ground: 609, 640.

The original code is 609 (in service since 1957). As the area ran low on numbers, regulators added overlay codes on top instead of splitting the city, so longtime residents kept their numbers while new lines received a newer code.

Code	Area served	In service
609	Central and southern New Jersey: Trenton, Princeton, Atlantic City and the Jersey Shore south	January 1, 1957
640	Central and southern New Jersey: Trenton, Princeton, Atlantic City and the Jersey Shore south	September 17, 2018

Nearby cities sharing these area codes

• Hamilton
• Atlantic City
• Princeton
• Ewing
• Lawrence
• Egg Harbor Township
• Galloway
• Willingboro
• Pleasantville
• Ocean City
• Wildwood
• Cape May
• Mount Holly

How to pick an area code for a new number

When you activate a new line in Trenton, the carrier assigns whichever code has numbers available — you usually can't choose. If a specific code matters to you (for example the prestige of 609), ask the carrier whether any blocks remain, or request a number transfer. All codes here dial identically and cost the same.

Dialing in Trenton

Because Trenton is an overlay area, 10-digit dialing is mandatory: always dial the area code plus the seven-digit number, even for a neighbor. See 10-digit dialing and overlay area codes for the background. For every code in New Jersey, visit the New Jersey area codes page.