Area Code 640
New Jersey
Area code 640 serves New Jersey, primarily Trenton, in the Eastern Time (ET) time zone. It is an overlay area code sharing territory with area code 609.
Overlay Area Code
This area code is part of an overlay region, meaning the same geographic area is served by multiple area codes. Overlay codes were introduced to meet growing demand for phone numbers without requiring existing customers to change their numbers.
This area code shares its geographic region with: area code 609 (Trenton).
In service since: 17-Sep-2018
Demographics & Economics
- Total Population
- 1,514,367
- Population Density
- 756 people/sq miabove U.S. average (U.S.: 93 people/sq mi)
- Median Household Income
- $96,333above U.S. median (U.S.: $75,144)
- Poverty Rate
- 9.7%below U.S. average (U.S.: 11.5%)
- Unemployment Rate
- 6.1%above U.S. average (U.S.: 3.6%)
- Education Attainment
- Bachelor's Degree+40.9%above U.S. average (U.S.: 33.7%)High School or Lower30.7%
Statistics are population-weighted aggregations from Census ACS 5-year estimates. Population figures are approximate — see Sources & Methodology for details on how area code populations are derived.
See how this area code compares to all US area codes in the Statistics dashboard.
Time Zone
- Eastern Time (ET)
NANPA Relief Status
According to the latest NANPA analysis (July 2026), this area code is not currently listed as exhausting within the next 36 months. No relief planning is in progress for this NPA.
Source: NANPA NPA Relief Planning Reports · See all relief planning statuses
Current Time
Prefix Utilization
Geographic Coverage
State
NJ
Major Cities
- Trenton
- Princeton
- Pleasantville
- Ocean Acres
- Princeton Meadows
- Hammonton
- Mercerville
- Hamilton Square
- Somers Point
- White Horse
- Burlington
- Villas
- Browns Mills
- Monmouth Junction
- Smithville
- Absecon
- Northfield
- Twin Rivers
- Pomona
- Fort Dix
- Brigantine
- Mystic Island
- Linwood
- Heathcote
and 125 more cities
Demographics
The estimated population served by area code 640 is approximately 1,514,367. The population density is 756 people per square mile, which is higher than the national average of 93. The median household income is $96,333, which is higher than the national median of $75,144. Approximately 40.9% of adults hold a bachelor's degree or higher, compared to the national rate of 33.7%. This rate is higher than the national average. The poverty rate stands at 9.7%, which is lower than the national rate of 11.5%.
History
Area code 640 serves as an overlay for the same territory as area code 609. It was introduced in 2018 to provide additional phone number capacity for the region. It shares its territory with area code area code 609.
County Coverage
Population-weighted county share based on aggregated ZCTA population (100% = total mapped population for area code 640).
| County | Population | Share |
|---|---|---|
| Mercer, NJ | 428,148 | 28.3% |
| Burlington, NJ | 358,094 | 23.6% |
| Atlantic, NJ | 267,785 | 17.7% |
| Ocean, NJ | 131,737 | 8.7% |
| Cape May, NJ | 96,045 | 6.3% |
| Middlesex, NJ | 82,899 | 5.5% |
| Somerset, NJ | 62,447 | 4.1% |
| Monmouth, NJ | 34,933 | 2.3% |
| Camden, NJ | 23,385 | 1.5% |
| Hunterdon, NJ | 20,655 | 1.4% |
| Cumberland, NJ | 8,239 | 0.5% |
Area Code 640 Family Tree
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Area code 640 was originally assigned in 17-Sep-2018 to serve NJ.
Call Context
This area code covers a geographic region across NJ, including Trenton and surrounding communities.
Nearby Area Codes
Area codes geographically closest to 640.
Other Area Codes in New Jersey
Area codes that also serve New Jersey, linked for easy comparison.