| 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 |
|---|---|---|---|
| 603-577 | Nashua | Hillsborough | Landline |
| 603-492 | Manchester | Hillsborough | Wireless |
| 603-833 | Rochester | Strafford | Wireless |
| 603-961 | Chichester | Merrimack | Landline |
| 603-912 | Salem | Rockingham | Landline |
| 603-394 | Newton | Rockingham | Landline |
| 603-864 | Nashua | Hillsborough | Landline |
| 603-855 | Alton Bay | Belknap | Landline |
| 603-396 | Merrimack | Hillsborough | Wireless |
| 603-968 | Ashland | Grafton | Landline |
| 603-644 | Manchester | Hillsborough | Landline |
| 603-543 | Claremont | Sullivan | Landline |
| 603-361 | Manchester | Hillsborough | Landline |
| 603-296 | Manchester | Hillsborough | Landline |
| 603-224 | Concord | Merrimack | Landline |
| 603-834 | Dover | Strafford | Landline |
| 603-226 | Concord | Merrimack | Landline |
| 603-709 | Plainfield | Sullivan | Landline |
| 603-204 | Nashua | Hillsborough | Wireless |
| 603-729 | Tilton | Belknap | Landline |