Residential delivery area · California
ZIP Code 91765: Diamond Bar, CA
ZIP code 91765 is in Diamond Bar, California, entirely in Los Angeles County (Census 2020 ZIP-county file). About 45,000 people live there (Census Bureau, ACS 2020-2024). Median household income is $105,565 (Census Bureau, ACS 2020-2024). By Census place, 70% of its land lies in Diamond Bar; 30% is outside any Census place.
- ACS2020-24
- Census2020
- FHFA2025
- ZBP2023
- IRS2022
- Town
- Diamond Bar · its only residential ZIP
- County
- Los Angeles County
- Census places
- Diamond Bar
- Metro area
- Los Angeles-Long Beach-Anaheim, CA
- House district
- CA-38 119th Congress
- State
- California
- Time zone
- Pacific
- Land area
- 18.6 sq mi · 2,397 people per sq mi
Where is ZIP code 91765?
91765 centers on 33.985°, -117.812° and covers 18.6 square miles of land plus 0.0 of water. It borders 6 ZIP codes: 91789, 92821, 91766, 91748, 91768, 91709.
The map draws ZIP code areas only. For the streets inside 91765, 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 91765 compare with the rest of Los Angeles County?
| Measure | 91765 | In Los Angeles County | In CA |
|---|---|---|---|
| People (ACS 2020-2024) | 44,502 | 76th of 301 | 314th of 1,802 |
| Median household income | $106k | 95th of 265 | 503rd of 1,189 |
| Median home value | $915k | 114th of 273 | 418th of 1,317 |
Its median household income is higher than in 84% of U.S. residential ZIP codes, and it is denser than 86% 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 91765?
The 2020 Census counted 46,449 people in 91765; the ACS, which samples households over 2020-2024, estimates 44,502. Between the 2010 and 2020 censuses its population fell 0.0% (its boundary stayed at least 90% the same).
- People, ACS 2020-2024
- 44,502
- 2020 Census count
- 46,449−0.0% since 2010 (46,457)
- Households
- 15,233
- Median age
- 46.0
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 91765?
Of the 44,502 people the ACS estimates in 91765, 18.5% are under 18 and 21.9% are 65 or older. The largest group by race and Hispanic origin is Asian (not Hispanic) (61.9%), then Hispanic or Latino (17.3%).
- Under 1818.5%
- 18 to 6459.6%
- 65 and older21.9%
- Asian, not Hispanic61.9%
- Hispanic or Latino17.3%
- White, not Hispanic12.1%
- Other or two or more5.2%
- Black, not Hispanic3.4%
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 91765 earn?
Median household income is $105,565 (ACS 2020-2024), the 95th highest of the 265 ranked ZIP codes in Los Angeles County. It fell from $123,288 in 2015-2019 (in 2024 dollars), a change larger than the surveys' margins of error.
- Median household income
- $105,565
- Income per person
- $48,949
- Below the poverty line
- 10.7%
- Unemployed (of the labor force)
- 5.0%
- Adults 25+ with a bachelor's degree
- 53.7%
- Adjusted gross income per tax return, 2022
- $110,36622,800 returns; wages 63% 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 91765?
FHFA's house price index for 91765, built from repeat sales and appraisals of the same homes, rose 73% from 2015 to 2025 and rose 53% from 2020 to 2025, and moved +5.9% in 2025.
- Median home value (owners' estimate)
- $915,100
- Median gross rent
- $2,486
- Homes owned by their occupants
- 77.5%
- Housing units
- 16,078
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 91765?
1,793 business establishments had a location in this ZIP code in 2023, 290 more than in 2018; the most are in professional, scientific, and technical services (ZIP Code Business Patterns).
- Professional, scientific, and technical services301
- Wholesale trade231
- Health care and social assistance223
- Transportation and warehousing181
- Real estate and rental and leasing162
- Accommodation and food services120
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 91765?
| ZIP | Town | People | Household income | Distance |
|---|---|---|---|---|
| 91789 | Walnut | 40,298 | $126k | 3.4 mi |
| 92821 | Brea | 41,623 | $124k | 4.4 mi |
| 91766 | Pomona | 69,327 | $82k | 5.1 mi |
| 91748 | Rowland Heights | 42,463 | $83k | 5.2 mi |
| 91768 | Pomona | 34,200 | $76k | 5.6 mi |
| 91709 | Chino Hills | 78,006 | $126k | 5.7 mi |
| 92823 | Brea | 5,846 | $170k | 4.0 mi (near) |
| 91792 | West Covina | 30,629 | $95k | 5.8 mi (near) |
Source: PlainZIP from the Census 2020 ZCTA boundaries (shared edges) and internal points; figures ACS 2020-2024.