Market insights · New Hampshire
Merrimack County, NH: growth, migration and housing
Merrimack County has 158,078 residents, up 2.6% since 2020 (+0.3% in the last year). In 2022–2023, 4,824 households moved in and 4,452 moved out (+372 net), bringing in a net $59.9M of income. Median household income is $97,004, the median home $367,600 and median rent $1,360 a month.
In New Hampshire: 4th of 10 counties for 5-year population growth · 5th of 10 counties for net in-migration (per resident) · 3rd of 10 counties for median household income · 5th of 10 counties for median home value.
Where new residents came from
Top counties by households (tax returns) moving to Merrimack County, 2022–2023 (IRS).
| From | Households (tax returns) | Their income (AGI) |
|---|---|---|
| Hillsborough County, NH | 1,362 | $135.0M |
| Rockingham County, NH | 473 | $33.9M |
| Belknap County, NH | 424 | $24.9M |
| Grafton County, NH | 205 | $16.8M |
| Middlesex County, MA | 177 | $19.4M |
| Strafford County, NH | 140 | $7.5M |
| Essex County, MA | 112 | $11.3M |
| Sullivan County, NH | 100 | $12.4M |
Where leavers went
Top counties by households leaving Merrimack County, 2022–2023 (IRS).
| To | Households (tax returns) | Their income (AGI) |
|---|---|---|
| Hillsborough County, NH | 1,059 | $71.5M |
| Belknap County, NH | 396 | $26.9M |
| Rockingham County, NH | 384 | $41.4M |
| Grafton County, NH | 208 | $15.4M |
| Strafford County, NH | 132 | $9.3M |
| Middlesex County, MA | 128 | $9.2M |
| Sullivan County, NH | 121 | $11.9M |
| Suffolk County, MA | 79 | $5.0M |
BizyFi in Merrimack County
3 companies in the BizyFi directory are based here. Search them on the company map (company names with a free account), or browse New Hampshire companies.
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Sources: U.S. Census Bureau population estimates (vintage 2025), American Community Survey 5-year (2024), and IRS Statistics of Income county-to-county migration data (2022–2023). Migration counts are tax returns (roughly households) moving between U.S. counties; the IRS suppresses very small flows. Growth rates, per-1,000 figures, rent share and state ranks are BizyFi calculations. Data updated 2026-10-17. This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau.