County demographics · Massachusetts
Middlesex County, Massachusetts demographics
Middlesex County, Massachusetts (county FIPS 25017) has a median household income of $130,847 (±$1,164) and a total population of 1,638,365 in the American Community Survey 5-year estimates for 2020-2024.
Margins of error are at the 90% confidence level. The figures describe 2020-2024 (dollars in 2024 dollars), not the present. 83 ZIP Code Tabulation Areas overlap the county (Census 2020).
Data as of Oct 22, 2026 (Olympus publication) · Markdown version
- Values are ACS 5-year estimates for 2020-2024 (dollars in 2024 dollars), not current figures.
- ZCTA-county overlaps come from the Census 2020 relationship file and use 2020 counties, by land area; Connecticut uses its legacy counties, not the planning regions in ACS 2022+.
ACS 5-year estimates, 2020-2024
Census American Community Survey 5-year estimates for 2020-2024, with 90% margins of error as published by the Census Bureau.
| Metric | Estimate | Margin of error (90%) | ACS table |
|---|---|---|---|
| Total population | 1,638,365 | none (controlled estimate) | B01003 |
| Median age | 38.9 years | ±0.2 years | B01002 |
| Households | 634,215 | ±1,681 | B11001 |
| Median household income (inflation-adjusted to the final ACS year) | $130,847 | ±$1,164 | B19013 |
| Median value of owner-occupied housing units | $727,800 | ±$3,891 | B25077 |
| Median gross rent | $2,201 | ±$17 | B25064 |
| Owner-occupied share of occupied housing units | 61.3% | none (derived from several estimates) | B25003 (derived) |
| Renter-occupied share of occupied housing units | 38.7% | none (derived from several estimates) | B25003 (derived) |
| High school graduate or higher (age 25+) | 93.2% | none (derived from several estimates) | B15003 (derived) |
| Bachelor's degree or higher (age 25+) | 59.5% | none (derived from several estimates) | B15003 (derived) |
| Share of people below the poverty level | 7.7% | none (derived from several estimates) | B17001 (derived) |
| Unemployment rate (civilian labor force) | 4.4% | none (derived from several estimates) | B23025 (derived) |
- Dollar values are in 2024 inflation-adjusted dollars.
- Percentages' margins of error are in percentage points (pp).
Geography
| Measure | Value |
|---|---|
| County FIPS | 25017 |
| Land area | 817.88 sq mi |
| Water area | 29.07 sq mi |
| Population density | 2,003 per sq mi of land |
| Geography vintage | 2024 Gazetteer |
ZIP codes (ZCTAs) in this county
ZCTAs that overlap the county in the Census 2020 ZCTA to county relationship file, largest share of the county's land first.
| ZCTA | Share of county land | Share of ZCTA land | County is the ZCTA's primary county |
|---|---|---|---|
| 01450 | 4% | 100% | Yes |
| 01886 | 3.7% | 100% | Yes |
| 01748 | 3.2% | 100% | Yes |
| 01776 | 3% | 100% | Yes |
| 01742 | 2.9% | 100% | Yes |
| 01431 | 2.9% | 100% | Yes |
| 01463 | 2.8% | 100% | Yes |
| 01469 | 2.6% | 100% | Yes |
| 01752 | 2.6% | 100% | Yes |
| 01826 | 2.5% | 99.4% | Yes |
| 01876 | 2.5% | 99.2% | Yes |
| 01720 | 2.4% | 100% | Yes |
| 01746 | 2.3% | 100% | Yes |
| 01824 | 2.2% | 100% | Yes |
| 01775 | 2.1% | 100% | Yes |
| 01887 | 2.1% | 100% | Yes |
| 01701 | 2.1% | 100% | Yes |
| 02493 | 2.1% | 100% | Yes |
| 01879 | 2% | 100% | Yes |
| 01821 | 2% | 100% | Yes |
| 01460 | 2% | 100% | Yes |
| 01827 | 2% | 100% | Yes |
| 01770 | 1.9% | 100% | Yes |
| 01741 | 1.9% | 100% | Yes |
| 01464 | 1.8% | 100% | Yes |
| 01778 | 1.8% | 100% | Yes |
| 01760 | 1.8% | 100% | Yes |
| 01773 | 1.7% | 100% | Yes |
| 01864 | 1.6% | 100% | Yes |
| 01801 | 1.6% | 100% | Yes |
| 01730 | 1.5% | 100% | Yes |
| 01721 | 1.5% | 100% | Yes |
| 01749 | 1.4% | 100% | Yes |
| 01803 | 1.4% | 100% | Yes |
| 01474 | 1.4% | 100% | Yes |
| 01719 | 1.3% | 100% | Yes |
| 01867 | 1.2% | 100% | Yes |
| 02421 | 1.2% | 100% | Yes |
| 01862 | 1.1% | 100% | Yes |
| 01432 | 1% | 100% | Yes |
| 01702 | 1% | 100% | Yes |
| 02155 | 1% | 100% | Yes |
| 01880 | 0.9% | 100% | Yes |
| 02420 | 0.9% | 100% | Yes |
| 01890 | 0.7% | 100% | Yes |
| 02180 | 0.7% | 100% | Yes |
| 02451 | 0.7% | 100% | Yes |
| 01754 | 0.6% | 100% | Yes |
| 02148 | 0.6% | 100% | Yes |
| 02459 | 0.6% | 100% | Yes |
| 01852 | 0.6% | 100% | Yes |
| 02176 | 0.6% | 100% | Yes |
| 02478 | 0.6% | 100% | Yes |
| 01863 | 0.5% | 100% | Yes |
| 02472 | 0.5% | 100% | Yes |
| 01854 | 0.5% | 100% | Yes |
| 02452 | 0.5% | 100% | Yes |
| 02453 | 0.4% | 100% | Yes |
| 02149 | 0.4% | 99.9% | Yes |
| 01851 | 0.4% | 100% | Yes |
| 02474 | 0.4% | 100% | Yes |
| 02138 | 0.3% | 100% | Yes |
| 01731 | 0.3% | 100% | Yes |
| 02465 | 0.3% | 100% | Yes |
| 02476 | 0.3% | 100% | Yes |
| 02458 | 0.2% | 100% | Yes |
| 02466 | 0.2% | 100% | Yes |
| 02139 | 0.2% | 100% | Yes |
| 02143 | 0.2% | 100% | Yes |
| 02468 | 0.2% | 100% | Yes |
| 02461 | 0.2% | 100% | Yes |
| 02467 | 0.2% | 29% | |
| 02145 | 0.2% | 100% | Yes |
| 01850 | 0.2% | 100% | Yes |
| 02460 | 0.2% | 100% | Yes |
| 02140 | 0.1% | 100% | Yes |
| 01434 | 0.1% | 17.2% | |
| 02144 | 0.1% | 100% | Yes |
| 02462 | 0.1% | 100% | Yes |
| 02141 | 0.1% | 100% | Yes |
| 02464 | 0.1% | 100% | Yes |
| 02142 | 0% | 100% | Yes |
| 01718 | 0% | 100% | Yes |
Sources
- American Community Survey 5-year estimates (Census Data API) — U.S. Census Bureau. ACS 5-year 2020-2024 (release acs5-2024:county), source date 2025-09-02. https://api.census.gov/data/2024/acs/acs5?get=NAME,B01003_001E,B01003_001M,B01002_001E,B01002_001M,B11001_001E,B11001_001M,B19013_001E,B19013_001M,B25077_001E,B25077_001M,B25064_001E,B25064_001M,B25003_001E,B25003_002E,B25003_003E,B15003_001E,B15003_017E,B15003_018E,B15003_019E,B15003_020E,B15003_021E,B15003_022E,B15003_023E,B15003_024E,B15003_025E,B17001_001E,B17001_002E,B23025_003E,B23025_005E&for=county:017&in=state:25
- Published by Olympus on Oct 22, 2026.
- Source data: U.S. Census Bureau. Works of the U.S. government are not subject to copyright in the United States.
- This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau.
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curl -s "https://api.olympus.new-odyssey.com/v1/geo-demographics/counties/25017" -H "X-API-Key: $OLYMPUS_API_KEY"get_us_demographics {"county_fips":"25017"}