| Place Name | Chelmsford |
| Place Type | Town |
| ZIP Code(s) | 01824 |
| County | Middlesex County |
| Area Code(s) | 351,978 |
| Timezone | Eastern Daylight Time (EDT) |
| Population (2021) | 36,271 |
| Majority Ethnicity | White 84.99% |
| Metro/Micro Stats Area | Boston-Cambridge-Newton, MA-NH |
| US Congressional District(s) | Massachusetts 3rd |
| State House Districts | 2nd Middlesex,14th Middlesex,16th Middlesex,17th Middlesex |
| State Senate Districts | Third Middlesex |
| Race/Ethnicy | Percentage of Population (2021) |
|---|---|
| White | 84.99% |
| African American | 1.33% |
| Hispanic | 0.11% |
| Asian | 9.31% |
| Native American | 0% |
| Hawaiin/Pacific Islander | 4.26% |