Merrimack County's estimated 2025 population is 158,391 with a growth rate of 0.41% in the past year according to the most recent United States census data. Merrimack County is the 3rd largest county in New Hampshire. The 2010 population was 146,395 and has seen a growth of 8.19% since that time.
Data after 2023 is projected based on recent change
The racial composition of Merrimack County includes 91.39% White, and smaller percentages for Asian, Black or African American, other race, Native American, Native Hawaiian or Pacific Islander and multiracial populations.
Race | Population | Percentage (of total) |
|---|---|---|
| White | 141,676 | 91.39% |
| Two or more races | 6,993 | 4.51% |
| Asian | 2,512 | 1.62% |
| Black or African American | 2,478 | 1.6% |
| Other race | 1,019 | 0.66% |
| Native American | 297 | 0.19% |
| Native Hawaiian or Pacific Islander | 43 | 0.03% |
Married
Widowed
Divorced
Separated
Never Married
Merrimack County's average per capita income is $56,860. Household income levels show a median of $93,944. The poverty rate stands at 7.09%.
Name | Median | Mean |
|---|---|---|
| Married Families | $127,822 | $155,461 |
| Families | $116,752 | $142,912 |
| Households | $93,944 | $119,046 |
| Non Families | $49,688 | $63,875 |
Average Income
Median Household Income
Poverty Rate