| General Information about Area Code 603 | |
|---|---|
| Country | United States |
| State / Province / Territory | New Hampshire |
| Major City | Manchester |
| Time Zone | Eastern (UTC-05:00) |
| Prefix | Primary City | County | Phone Type |
|---|---|---|---|
| 603-446 | Marlow | Cheshire | Landline |
| 603-538 | Colebrook | Coos | Landline |
| 603-494 | Merrimack | Hillsborough | Wireless |
| 603-284 | South Tamworth | Carroll | Landline |
| 603-216 | Manchester | Hillsborough | Landline |
| 603-559 | Portsmouth | Rockingham | Landline |
| 603-399 | Westmoreland | Cheshire | Landline |
| 603-797 | Plaistow | Rockingham | Landline |
| 603-290 | Concord | Merrimack | Wireless |
| 603-393 | Gilford | Belknap | Wireless |
| 603-942 | Northwood | Rockingham | Landline |
| 603-359 | Lebanon | Grafton | Wireless |
| 603-880 | Nashua | Hillsborough | Landline |
| 603-655 | Manchester | Hillsborough | Wireless |
| 603-563 | Peterborough | Hillsborough | Landline |
| 603-634 | Manchester | Hillsborough | Landline |
| 603-569 | Wolfeboro | Carroll | Landline |
| 603-291 | Greenville | Hillsborough | Landline |
| 603-401 | Hampton | Rockingham | Wireless |
| 603-327 | Salem | Rockingham | Landline |