| Name | Middlesex County |
| State | Massachusetts |
| FIPS Code | 25017 |
| County Seat | Lowell |
| Timezone | Eastern Daylight Time (EDT) |
| Population (2024) | 1,644,932 |
| Population Growth Rate(2020-2024) | 0.79% |
| Majority Ethnicity | White 71.54% |
| Public School Majority Ethnicity | White 55% |
| Partisan Voting Index | Democratic:+20 |
| Unemployment Rate (May 2026) | 4.5% |
| Sales Tax Rate (2025) | 6.25% |
| Area Code(s) | 351 / 978 / 339 / 781 / 508 / 774 / 617 / 857 |
| Race/Ethnicity | Percentage of Population (2023) |
|---|---|
| White | 71.54% |
| African American | 5.22% |
| Hispanic | 9.32% |
| Asian | 13.68% |
| Native American | 0.19% |
| Hawaiin/Pacific Islander | 0.04% |
| Race/Ethnicity | Percentage of Public School Students (2023) |
|---|---|
| White | 54.79% |
| African American | 6.66% |
| Hispanic | 18.94% |
| Asian | 14.2% |
| Native American | 0.22% |
| Hawaiin/Pacific Islander | 0.07% |