Area Code 603
New Hampshire
Area code 603 serves New Hampshire, primarily Manchester, in the Eastern Time (ET) time zone. It has served the region since 01-Jan-1947.
Demographics & Economics
- Total Population
- 1,563,238
- Population Density
- 156 people/sq miabove U.S. average (U.S.: 93 people/sq mi)
- Median Household Income
- $100,436above U.S. median (U.S.: $75,144)
- Poverty Rate
- 7.2%below U.S. average (U.S.: 11.5%)
- Unemployment Rate
- 3.3%near U.S. average (U.S.: 3.6%)
- Education Attainment
- Bachelor's Degree+39.8%above U.S. average (U.S.: 33.7%)High School or Lower28.9%
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
NH
Major Cities
- Manchester
- Nashua
- Concord
- Dover
- Rochester
- Keene
- Portsmouth
- Derry
- Laconia
- Lebanon
- Claremont
- Londonderry
- Somersworth
- Durham
- Exeter
- Hampton
- Berlin
- Milford
- Franklin
- Hanover
- Hudson
- South Hooksett
- Newmarket
- Hooksett
and 77 more cities
Demographics
The estimated population served by area code 603 is approximately 1,563,238. The population density is 156 people per square mile, which is higher than the national average of 93. The median household income is $100,436, which is higher than the national median of $75,144. Approximately 39.8% 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 7.2%, which is lower than the national rate of 11.5%.
History
Area code 603 is one of the original area codes established in 1947 when the North American Numbering Plan (NANP) was created.
County Coverage
Population-weighted county share based on aggregated ZCTA population (100% = total mapped population for area code 603).
| County | Population | Share |
|---|---|---|
| Hillsborough, NH | 424,776 | 27.2% |
| Rockingham, NH | 390,096 | 25.0% |
| Merrimack, NH | 206,487 | 13.2% |
| Strafford, NH | 139,410 | 8.9% |
| Grafton, NH | 92,739 | 5.9% |
| Cheshire, NH | 85,762 | 5.5% |
| Belknap, NH | 74,318 | 4.8% |
| Sullivan, NH | 62,178 | 4.0% |
| Carroll, NH | 53,897 | 3.4% |
| Coos, NH | 33,575 | 2.1% |
Area Code 603 Family Tree
Area code 603 is an original area code with no splits or overlays. It has been in service since 01-Jan-1947.
Call Context
This area code covers a metropolitan region in NH with moderate to high population density, centered on Manchester and surrounding communities.
Nearby Area Codes
Area codes geographically closest to 603.
