| Incorporated: 1746 |
| |
| Origin: This territory was part of the 1673 charter of Dunstable, a large Massachusetts grant that was divided nearly in half with the establishment of the New Hampshire-Massachusetts border in 1741. Though the first log cabin was built here about 1665, settlement did not begin until the 1720s. When the town was separated from Dunstable (Nashua) in 1746, it was incorporated as Merrimack, after the river. In 1766, a ferry concession was granted to Edward Lutwyche, to facilitate trade and traffic between Litchfield and Merrimack. In 1784, the ferry was granted to Revolutionary War patriot Matthew Thornton, an area still known as Thornton's Ferry. Matthew Thornton was a resident of Merrimack until his death in 1803. |
| |
| Villages and Place Names: Reeds Ferry, Souhegan Village, South Merrimack, Thorntons Ferry |
| |
| Population, Year of the First Census Taken: 819 residents in 1790 |
| |
| Population Trends: Population change for Merrimack totaled 18,079 over 50 years, from 8,595 in 1970 to 26,674 in 2020, the fifth-largest 50-year increase among the cities and towns. The largest decennial percent change was a 71 percent increase from 1970 to 1980. The town's population increased by five percent from 2010 to 2020. The 2023 Census estimate for Merrimack was 28,916 residents, which ranked eighth among New Hampshire's incorporated cities and towns. |
| |
| Population Density and Land Area: 2023 (US Census Bureau): 887.0 persons per square mile of land area. Merrimack contains 32.6 square miles of land area and 0.8 square miles of inland water area. |
| |
| |
| |
