Dover, New Hampshire

Where Is Area Code 603?

Area code 603 serves the entire state of New Hampshire, including Dover. It is the only area code in New Hampshire, so it covers every region of the state, from the Seacoast to the White Mountains and the Connecticut River Valley.

Major cities in area code 603 include Dover, Manchester, Nashua, Concord, Portsmouth, Rochester, and Keene. The area code covers all 10 New Hampshire counties, including Strafford County, where Dover is located, as well as Hillsborough, Rockingham, Merrimack, and Grafton counties.

Area code 603 also covers well-known New Hampshire landmarks and regions. These include the White Mountain National Forest, Mount Washington, Lake Winnipesaukee, and the Seacoast near Portsmouth and Dover.

History of Area Code 603

Area code 603 was established in 1947 as one of the original area codes in the North American Numbering Plan. It has served New Hampshire from the start, and it was not created by splitting another area code.

Area code 603 has not had any geographic splits or overlay area codes. New Hampshire has kept a single statewide area code even as telephone service grew across cities such as Dover, Manchester, Nashua, and Concord.

Key Facts About Area Code 603

• Area code 603 is in New Hampshire, and Dover is one of the cities that uses it.
• Area code 603 is one of the original area codes created in 1947 under the North American Numbering Plan.
• Area code 603 covers the entire state of New Hampshire, not just one city or one county.
• Area code 603 uses the Eastern Time Zone.
• New Hampshire had a population of 1,377,529 at the 2020 United States Census, and area code 603 serves that statewide population.
• Dover is in Strafford County, and it is one of New Hampshire's oldest cities.
• Area code 603 includes major public institutions such as the University of New Hampshire in Durham and the New Hampshire State House in Concord.
• Area code 603 includes notable places such as Mount Washington, Lake Winnipesaukee, and the Portsmouth Naval Shipyard area near the Seacoast.

Frequently Asked Questions

What state is area code 603 in?

Area code 603 is in New Hampshire.

What major cities use area code 603?

Major cities in area code 603 include Dover, Manchester, Nashua, Concord, Portsmouth, Rochester, and Keene.

Is area code 603 a toll-free number?

No. Area code 603 is a geographic area code for New Hampshire.