Residential delivery area · Massachusetts
ZIP Code 02138: Cambridge, MA
ZIP code 02138 is in Cambridge, Massachusetts, entirely in Middlesex County (Census 2020 ZIP-county file). About 39,000 people live there (Census Bureau, ACS 2020-2024), the 2nd most populous of Cambridge's 5 residential ZIP codes. Median household income is $119,967 (Census Bureau, ACS 2020-2024).
- ACS2020-24
- Census2020
- FHFA2021
- ZBP2023
- IRS2022
- Town
- Cambridge · 5 residential ZIPs
- County
- Middlesex County
- Census places
- Cambridge
- Neighborhoods
- Huron Village, Larchwood, Strawberry Hill GeoNames
- Metro area
- Boston-Cambridge-Newton, MA-NH
- House districts
- MA-5 (93%), MA-7 (7%) 119th Congress, by share of land
- State
- Massachusetts
- Time zone
- Eastern
- Land area
- 2.7 sq mi · 14,065 people per sq mi
- PO Box ZIPs
- 02238 also use the name Cambridge
Where is ZIP code 02138?
02138 centers on 42.380°, -71.135° and covers 2.7 square miles of land plus 0.3 of water. It borders 7 ZIP codes: 02140, 02134, 02143, 02139, 02135, 02472, 02478.
The map draws ZIP code areas only. For the streets inside 02138, open its center on OpenStreetMap.
Source: U.S. Census Bureau, 2020 ZCTA cartographic boundaries and the 2023 Gazetteer (2020 ZCTAs); ZIP-to-county shares, Census places and House districts (119th Congress) from the Census 2020 relationship files (shares of land); metro area from the OMB delineation (July 2023); town name and time zone from simplemaps US ZIP Codes (CC BY 4.0); neighborhoods from the GeoNames gazetteer (CC BY 4.0), placed in this ZIP code by PlainZIP.
How does 02138 compare with the rest of Cambridge?
| Measure | 02138 | In Cambridge | In Middlesex County | In MA |
|---|---|---|---|---|
| People (ACS 2020-2024) | 38,509 | 2nd of 5 | 8th of 83 | 33rd of 539 |
| Median household income | $120k | 5th of 5 | 61st of 78 | 175th of 406 |
| Median home value | $1.21M | 2nd of 5 | 10th of 80 | 20th of 449 |
Its median household income is higher than in 90% of U.S. residential ZIP codes, and it is denser than 99% of all U.S. residential ZIP codes. ZIP codes at the ACS caps ($250,000 or more for household income, $2,000,000 or more for home value) share the top rank.
Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates (B01003, B19013, B25077); ranks by PlainZIP over residential ZIP codes (ZCTAs).
How many people live in 02138?
The 2020 Census counted 37,982 people in 02138; the ACS, which samples households over 2020-2024, estimates 38,509. Between the 2010 and 2020 censuses its population grew 4.6% (its boundary stayed at least 90% the same).
- People, ACS 2020-2024
- 38,509
- 2020 Census count
- 37,982+4.6% since 2010 (36,314)
- Households
- 14,169
- Median age
- 28.3
Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates (B01003, B01002, B11001); 2020 Census (DHC P1); 2010 Census (SF1 P1).
Who lives in 02138?
Of the 38,509 people the ACS estimates in 02138, 13.1% are under 18 and 14.4% are 65 or older. The largest group by race and Hispanic origin is White (not Hispanic) (58.8%), then Asian (not Hispanic) (17.0%).
- Under 1813.1%
- 18 to 6472.5%
- 65 and older14.4%
- White, not Hispanic58.8%
- Asian, not Hispanic17.0%
- Hispanic or Latino10.0%
- Other or two or more7.5%
- Black, not Hispanic6.7%
Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates (B01001 age by sex, B03002 Hispanic or Latino origin by race); shares of the estimated population, small ZIP codes carry wide margins.
What do households in 02138 earn?
Median household income is $119,967 (ACS 2020-2024), the 61st highest of the 78 ranked ZIP codes in Middlesex County. It is not measurably different from 2015-2019 ($128,914 in 2024 dollars): the change is within the surveys' margins of error.
- Median household income
- $119,967
- Income per person
- $75,496
- Below the poverty line
- 13.5%
- Unemployed (of the labor force)
- 3.3%
- Adults 25+ with a bachelor's degree
- 85.6%
- Adjusted gross income per tax return, 2022
- $280,51114,470 returns; wages 41% of AGI (IRS)
Source: U.S. Census Bureau, ACS 2020-2024 and 2015-2019 5-year estimates (B19013, B19301, B17001, B23025, B15003; 2015-2019 dollars converted with the BLS CPI-U, 1.22699); IRS Statistics of Income, ZIP code data, tax year 2022 (adjusted gross income per return, filed under the address on the return).
What are homes worth in 02138?
- Median home value (owners' estimate)
- $1,212,400
- Median gross rent
- $2,772
- Homes owned by their occupants
- 41.9%
- Housing units
- 16,043
Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates (B25077, B25064, B25003, B25001); FHFA House Price Index, annual five-digit ZIP, updated 2026-03-31.
What businesses are in 02138?
1,072 business establishments had a location in this ZIP code in 2023, 87 fewer than in 2018; the most are in professional, scientific, and technical services (ZIP Code Business Patterns).
- Professional, scientific, and technical services215
- Accommodation and food services159
- Health care and social assistance139
- Other services (except public administration)113
- Retail trade107
- Real estate and rental and leasing65
Source: U.S. Census Bureau, ZIP Code Business Patterns 2023 and 2018 (establishments with paid employees, by the business's ZIP code).
Which ZIP codes are next to 02138?
| ZIP | Town | People | Household income | Distance |
|---|---|---|---|---|
| 02140 | Cambridge | 21,204 | $135k | 0.9 mi |
| 02134 | Allston | 17,667 | $79k | 1.5 mi |
| 02143 | Somerville | 25,513 | $131k | 2.0 mi |
| 02139 | Cambridge | 40,033 | $135k | 2.1 mi |
| 02135 | Brighton | 43,149 | $91k | 2.3 mi |
| 02472 | Watertown | 35,620 | $126k | 2.3 mi |
| 02478 | Belmont | 27,175 | $183k | 2.5 mi |
| 02163 | Boston | 1,817 | $85k | 1.0 mi (near) |
| 02144 | Somerville | 25,448 | $150k | 1.5 mi (near) |
Source: PlainZIP from the Census 2020 ZCTA boundaries (shared edges) and internal points; figures ACS 2020-2024.