Residential delivery area · Massachusetts
ZIP Code 02478: Belmont, MA
ZIP code 02478 is in Belmont, Massachusetts, entirely in Middlesex County (Census 2020 ZIP-county file). About 27,000 people live there (Census Bureau, ACS 2020-2024). Median household income is $183,137 (Census Bureau, ACS 2020-2024).
- ACS2020-24
- Census2020
- FHFA2025
- ZBP2023
- IRS2022
- Town
- Belmont · its only residential ZIP
- County
- Middlesex County
- Census places
- Belmont census-designated place
- Metro area
- Boston-Cambridge-Newton, MA-NH
- House district
- MA-5 119th Congress
- State
- Massachusetts
- Time zone
- Eastern
- Land area
- 4.6 sq mi · 5,850 people per sq mi
Where is ZIP code 02478?
02478 centers on 42.395°, -71.180° and covers 4.6 square miles of land plus 0.1 of water. It borders 8 ZIP codes: 02476, 02472, 02452, 02474, 02140, 02138, 02453, 02421.
The map draws ZIP code areas only. For the streets inside 02478, 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).
How does 02478 compare with the rest of Middlesex County?
| Measure | 02478 | In Middlesex County | In MA |
|---|---|---|---|
| People (ACS 2020-2024) | 27,175 | 23rd of 83 | 80th of 539 |
| Median household income | $183k | 20th of 78 | 39th of 406 |
| Median home value | $1.16M | 17th of 80 | 30th of 449 |
Its median household income is higher than in 98% of U.S. residential ZIP codes, and it is denser than 95% 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 02478?
The 2020 Census counted 27,286 people in 02478; the ACS, which samples households over 2020-2024, estimates 27,175. Between the 2010 and 2020 censuses its population grew 10.6% (its boundary stayed at least 90% the same).
- People, ACS 2020-2024
- 27,175
- 2020 Census count
- 27,286+10.6% since 2010 (24,664)
- Households
- 10,412
- Median age
- 42.9
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 02478?
Of the 27,175 people the ACS estimates in 02478, 24.2% are under 18 and 19.3% are 65 or older. The largest group by race and Hispanic origin is White (not Hispanic) (68.8%), then Asian (not Hispanic) (19.5%).
- Under 1824.2%
- 18 to 6456.6%
- 65 and older19.3%
- White, not Hispanic68.8%
- Asian, not Hispanic19.5%
- Other or two or more5.2%
- Hispanic or Latino4.9%
- Black, not Hispanic1.6%
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 02478 earn?
Median household income is $183,137 (ACS 2020-2024), the 20th highest of the 78 ranked ZIP codes in Middlesex County. It rose from $158,661 in 2015-2019 (in 2024 dollars), a change larger than the surveys' margins of error.
- Median household income
- $183,137
- Income per person
- $95,484
- Below the poverty line
- 3.6%
- Unemployed (of the labor force)
- 4.3%
- Adults 25+ with a bachelor's degree
- 80.9%
- Adjusted gross income per tax return, 2022
- $256,49512,920 returns; wages 58% 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 02478?
FHFA's house price index for 02478, built from repeat sales and appraisals of the same homes, rose 49% from 2015 to 2025 and rose 24% from 2020 to 2025, and moved −7.7% in 2025.
- Median home value (owners' estimate)
- $1,159,000
- Median gross rent
- $2,527
- Homes owned by their occupants
- 64.7%
- Housing units
- 10,881
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 02478?
623 business establishments had a location in this ZIP code in 2023, 16 more than in 2018; the most are in health care and social assistance (ZIP Code Business Patterns).
- Health care and social assistance97
- Professional, scientific, and technical services92
- Other services (except public administration)76
- Retail trade62
- Accommodation and food services60
- Construction54
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 02478?
| ZIP | Town | People | Household income | Distance |
|---|---|---|---|---|
| 02476 | Arlington | 17,708 | $151k | 1.5 mi |
| 02472 | Watertown | 35,620 | $126k | 1.8 mi |
| 02452 | Waltham | 15,808 | $118k | 2.0 mi |
| 02474 | Arlington | 28,642 | $151k | 2.2 mi |
| 02140 | Cambridge | 21,204 | $135k | 2.4 mi |
| 02138 | Cambridge | 38,509 | $120k | 2.5 mi |
| 02453 | Waltham | 31,591 | $115k | 3.6 mi |
| 02421 | Lexington | 18,080 | $228k | 4.3 mi |
| 02144 | Somerville | 25,448 | $150k | 2.9 mi (near) |
| 02458 | Newton | 13,050 | $154k | 2.9 mi (near) |
Source: PlainZIP from the Census 2020 ZCTA boundaries (shared edges) and internal points; figures ACS 2020-2024.