| 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 |
|---|---|---|---|
| 603-683 | Merrimack | Hillsborough | Landline |
| 603-448 | Lebanon | Grafton | Landline |
| 603-537 | Derry | Rockingham | Landline |
| 603-478 | Hillsborough | Hillsborough | Landline |
| 603-289 | Manchester | Hillsborough | Wireless |
| 603-650 | Hanover | Grafton | Landline |
| 603-757 | Keene | Cheshire | Landline |
| 603-978 | Dover | Strafford | Wireless |
| 603-455 | Gilford | Belknap | Wireless |
| 603-208 | Lyme | Grafton | Wireless |
| 603-449 | Milan | Coos | Landline |
| 603-988 | Portsmouth | Rockingham | Landline |
| 603-694 | North Conway | Carroll | Landline |
| 603-895 | Raymond | Rockingham | Landline |
| 603-294 | Portsmouth | Rockingham | Landline |
| 603-421 | Derry | Rockingham | Landline |
| 603-250 | Center Barnstead | Belknap | Landline |
| 603-752 | Berlin | Coos | Landline |
| 603-788 | Lancaster | Coos | Landline |
| 603-217 | Bristol | Grafton | Landline |