| 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 |
|---|---|---|---|
| 603-851 | Manchester | Hillsborough | Wireless |
| 603-454 | Sunapee | Sullivan | Wireless |
| 603-620 | Merrimack | Hillsborough | Wireless |
| 603-436 | Portsmouth | Rockingham | Landline |
| 603-489 | Manchester | Hillsborough | Landline |
| 603-254 | Plymouth | Grafton | Wireless |
| 603-861 | Tamworth | Carroll | Landline |
| 603-636 | Groveton | Coos | Landline |
| 603-989 | Warren | Grafton | Landline |
| 603-312 | Dover | Strafford | Wireless |
| 603-307 | Intervale | Carroll | Wireless |
| 603-856 | Concord | Merrimack | Landline |
| 603-755 | Farmington | Strafford | Landline |
| 603-667 | Lebanon | Grafton | Landline |
| 603-728 | North Woodstock | Grafton | Landline |
| 603-616 | Littleton | Grafton | Wireless |
| 603-617 | Dover | Strafford | Landline |
| 603-680 | Hillsborough | Hillsborough | Wireless |
| 603-809 | Nashua | Hillsborough | Wireless |
| 603-363 | Westmoreland | Cheshire | Landline |