| City: | Walnut, California |
| City Alias: | City Industry, City Of Industry, Diamond Bar |
| County: | Los Angeles County |
| Timezone: | Pacific (GMT -08:00) |
| Local Time: | 8:20:49 PM |
| Population: | 41,235 [See All] |
| Area Codes: | 909 / 840 |
| Classification: | Standard [Normal Street Delivery] |
| Coordinates: | 34.0130, -117.8539 |
| Land Area: | 15.867 sq mi |
| Quick Link: |
ZIP Code 91789 has 41,235 residents and 13,047 households (average 3.16 persons per household). The median age is 45.8 years, significantly older than the state (37.5) and significantly older than the nation (38.8). The gender split is 48.7% male and 51.3% female, which is about the same as the state male share (49.4%), making this a female-majority area. Largest groups are Asian (66.6%, much higher than the state average of 15.4% and well above the national average of 6.0%) and Hispanic or Latino (19.1%); Hispanic or Latino residents make up 19.1%, which is much lower than the state average (39.4%), and Asian share is much higher than both the state (15.4%) and national averages (6.0%).
Explore More:Population Over TimeBy Age & GenderBy RaceBy GenderNativity & Citizenship
| 2020 Population: | 41,235Source: Census DHC |
| 2023 ACS Population Estimate: | 40,933Source: Census ACS |
| 2025 ZC Population Estimate: | 42,527Source: ZIP-Codes.com |
| Population Density: | 2,598.8 people per sq mile |
| Average Income: | $125,742Source: Census ACS |
| Households: | 13,047Source: Census DHC |
| Average House Value: | $936,800Source: Census ACS |
| Persons Per Household: | 3.16Source: Census DHC |
| Average Family Size: | 3.07Source: Census ACS |
| Group | 2010 | 2011 | 2102 | 2013 | 2014 | 2015 | 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Census ACS Population Estimate | -- | 42,292 | 42,332 | 42,609 | 43,369 | 43,805 | 43,973 | 44,115 | 44,474 | 44,440 | 43,531 | 41,829 | 41,377 | 40,933 |
| Decennial Census | 43,079 | -- | -- | -- | -- | -- | -- | -- | -- | -- | 41,235 | -- | -- | -- |
Median Age: 45.8
Male Median Age: 43.1
Female Median Age: 48.1
| Group | < 5 | 5-9 | 10-14 | 15-19 | 20-24 | 25-29 | 30-34 | 35-39 | 40-44 | 45-49 | 50-54 | 55-59 | 60-64 | 65-69 | 70-74 | 75-79 | 80-84 | 85+ |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Male | 788 | 1,023 | 1,171 | 1,371 | 1,444 | 1,314 | 1,132 | 1,131 | 1,083 | 1,176 | 1,356 | 1,460 | 1,573 | 1,451 | 1,214 | 688 | 428 | 280 |
| Female | 720 | 942 | 1,054 | 1,215 | 1,223 | 1,190 | 1,023 | 1,159 | 1,224 | 1,450 | 1,535 | 1,744 | 1,844 | 1,688 | 1,393 | 797 | 489 | 462 |
| Total | 1,508 | 1,965 | 2,225 | 2,586 | 2,667 | 2,504 | 2,155 | 2,290 | 2,307 | 2,626 | 2,891 | 3,204 | 3,417 | 3,139 | 2,607 | 1,485 | 917 | 742 |
| White: | 5,426 | 12.00% |
| Black: | 951 | 2.10% |
| Hispanic:* | 7,863 | 17.38% |
| Asian: | 27,454 | 60.69% |
| American Indian: | 189 | 0.42% |
| Hawaiian: | 33 | 0.07% |
| Other: | 3,319 | 7.34% |
| Total: | 45,235 | 100% |
| Gender | Count | % | Median Age |
|---|---|---|---|
| Males: | 20,083 | 48.70% | 43.1 years |
| Females: | 21,152 | 51.30% | 48.1 years |
| Total: | 41,235 | 100% | 45.8 years |
| Native, born in the United States: | 19,530 | 47.71% |
| Native, born in PR, Island Areas, or abroad: | 611 | 1.49% |
| Foreign born, naturalized U.S. citizen: | 14,671 | 35.84% |
| Foreign born, not a U.S. citizen: | 6,121 | 50.80% |
| Total Population: | 40,933 | 100% |
| Total Native Population: | 20,141 | 49.20% |
| Total Foreign-born Population: | 20,792 | 50.80% |
In 2023, the Median household income is $125,742, which is much higher than the national median ($78,538), is up $35,105 (38.7%) since 2011 and above its 2019 pre-pandemic level by $23,901. Family households earn a median of $139,172 versus $56,348 for nonfamily households (a difference of $82,824). By gender, male median income is $80,296 and female is $70,648, which is considerably higher than the national female median ($53,445), with a current gap of $9,648 that has narrowed from 2011 to 2023. The labor-force participation rate is 59.2%, which is below the state rate (63.9%). The unemployment rate is 4.3%, which is much lower than the state rate (6.4%). The largest occupation group is Management (52.8%).
Explore More:Income Over TimeHousehold IncomeEmployment StatusBy Occupation
| Income Type | 2011 | 2012 | 2013 | 2014 | 2015 | 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Median Household Income | $90,637 | $90,906 | $91,623 | $93,509 | $93,301 | $93,231 | $95,081 | $99,398 | $101,841 | $105,848 | $116,583 | $123,555 | $125,742 |
| Median Family Income | $97,173 | $96,339 | $98,741 | $101,074 | $100,236 | $100,158 | $102,839 | $106,725 | $109,495 | $113,087 | $124,078 | $133,558 | $139,172 |
| Median NonFamily Income | $44,901 | $47,321 | $48,261 | $45,000 | $44,362 | $46,081 | $43,519 | $48,000 | $57,468 | $54,868 | $56,661 | $61,699 | $56,348 |
| Median Male Income | $61,185 | $62,623 | $63,113 | $62,903 | $62,384 | $62,364 | $61,909 | $63,260 | $62,758 | $64,180 | $68,188 | $75,346 | $80,296 |
| Median Female Income | $46,990 | $48,155 | $47,500 | $50,165 | $51,085 | $51,166 | $51,262 | $53,775 | $53,692 | $52,174 | $58,872 | $67,735 | $70,648 |
| Employed: | 19,171 | 56.66% |
| Unemployed: | 861 | 2.54% |
| Not In Labor Force: | 13,805 | 40.80% |
| Total: | 33,837 | 100% |
| Management, business, science, and arts: | 10,130 | 52.84% |
| Service: | 2,179 | 11.37% |
| Sales and Office: | 4,483 | 23.38% |
| Natural resources, construction, and maintenance: | 608 | 3.17% |
| Production, transportation, and material moving: | 1,771 | 9.24% |
| Total Civilian Employed Population: | 19,171 | 100% |
In 2023, the median home value is $936,800, which is far above the national median ($303,400), is up $324,300 (52.95%) since 2011 and above its 2019 pre-pandemic level by $201,900. The median gross rent is $2,868, which is considerably higher than the national median ($1,348), is up $1,031 (56.12%) since 2011 and above its 2019 pre-pandemic level by $596. Of occupied housing, owners make up 82.44% (60.15% with a mortgage, 39.85% free-and-clear) and renters 17.56% - making this ZIP Code more home ownership than the state and under national rental averages. The vacancy rate is 5.71%, which is considerably lower than the national rate (10.43%).
Explore More:Compare Home ValueHome Value Over TimeRent & Over TimeHousing Occupancy
| Group | 2011 | 2102 | 2013 | 2014 | 2015 | 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Median Home Value | $612,500 | $604,100 | $599,200 | $608,400 | $623,200 | $654,700 | $676,900 | $707,600 | $734,900 | $766,400 | $790,500 | $910,400 | $936,800 |
| Less than $500: | 7 | 0.31% |
| $500 to $999: | 6 | 0.27% |
| $1,000 to $1,499: | 119 | 5.33% |
| $1,500 to $1,999: | 107 | 4.79% |
| $2,000 to $2,499: | 398 | 17.82% |
| $2,500 to $2,999: | 442 | 19.79% |
| $3,000 or more: | 846 | 37.89% |
| No Rent: | 308 | 13.79% |
| Total: | 2,233 | 100% |
| Group | 2011 | 2102 | 2013 | 2014 | 2015 | 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Median Rent | $1,837 | $1,747 | $1,841 | $1,885 | $1,928 | $1,996 | $2,123 | $2,166 | $2,272 | $2,368 | $2,548 | $2,690 | $2,868 |
| Owner Occupied (with mortgage): | 6,306 | 49.59% |
| Owner Occupied (free and clear, no mortgage): | 4,177 | 32.85% |
| Renter Occupied: | 2,233 | 17.56% |
| Total Occupied Housing Units: | 12,716 | 100% |
| Occupied Housing Units: | 12,716 | 94.29% |
| Vacant Housing Units (not graphed): | 770 | 5.71% |
| Total Housing Units: | 13,486 | 100% |
| Single-Family Units: | 12,235 | 90.72% |
| Multi-Family Units: | 725 | 5.38% |
| Other Units: | 526 | 3.90% |
| Total Housing Units: | 13,486 | 100% |
In 2023, 53.20% of adults (25+) have a bachelor's degree or higher, which is far higher than the national rate (35.00%), well above both the state and national averages. High school or higher is 93.40%, which is markedly above the state rate (84.60%). The uninsured rate is 4.80%, which is falls below the national rate (8.60%). The share of people in poverty is 6.30%, which is falls below the national rate (8.70%), up 2.40 percentage points since 2011 and above its 2019 pre-pandemic level by 1.30 percentage points. This points to rising hardship - a weaker consumer base, greater strain on public services, and job-market headwinds. Among residents ages 3+, the largest enrollment group is elementary (36.97%). College enrollment is 34.77%, which is far higher than the national rate (26.70%), indicating the community is likely a college hub with student-driven housing and services.
Explore More:Educational AttainmentHealth InsurancePoverty Over TimeSchool Enrollment
| Less than 9th grade: | 1,121 | 3.70% |
| 9th to 12th grade, no diploma: | 865 | 2.86% |
| High school graduate (includes equivalency): | 4,859 | 16.05% |
| Some college, no degree: | 4,695 | 15.51% |
| Associate's degree: | 2,639 | 8.72% |
| Bachelor's degree: | 10,632 | 35.13% |
| Graduate or professional degree: | 5,458 | 18.03% |
| Total: | 30,269 | 100% |
| High school or higher: | 28,283 | 93.44% |
| Bachelor's degree or higher: | 16,090 | 53.16% |
| Private Insurance: | 28,700 | 63.94% |
| Public Insurance: | 14,226 | 31.70% |
| No Insurance: | 1,957 | 4.36% |
| Total: | 44,883 | 100% |
| Has Health Insurance: | 42,926 | 95.64% |
| Group | 2011 | 2102 | 2013 | 2014 | 2015 | 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| % of People in Poverty | 3.9% | 4.3% | 4.3% | 4.5% | 4.5% | 5.2% | 5.5% | 5.3% | 5.0% | 4.7% | 6.4% | 6.1% | 6.3% |
Note: Counts of Families & People in poverty are not published at the ZIP Code level due to small sample sizes. Percentages shown are survey estimates from the American Community Survey (ACS). They may differ from official poverty statistics. The U.S. Census Bureau defines poverty status by comparing a family's or individual's total income with federal poverty thresholds that vary by family size and composition.
| Nursery School, Preschool: | 407 | 4.09% |
| Kindergarten: | 733 | 7.37% |
| Elementary school (grades 1-8): | 3,677 | 36.97% |
| High school (grades 9-12): | 1,670 | 16.79% |
| College or graduate school: | 3,458 | 34.77% |
| Total: | 9,945 | 100% |
| Early Childhood: | 1,140 | 11.46% |
| K-12 (Primary & Secondary School): | 6,080 | 61.14% |
ZIP Code 91789 supports both business and residential activity. According to the Business Census (2023), there are 2,325 business establishments, employing about 21,957 people with an annual payroll of $1,345,373,000. USPS data shows 13,458 residential mailboxes and 1,805 business mailboxes, reflecting local delivery coverage.
| # Residential Mailboxes: | 13,458Source: USPS |
| # Business Mailboxes: | 1,805Source: USPS |
| Total Delivery Receptacles: | 14,393Source: USPS |
| Single Family Delivery Units: | 6,802Source: USPS |
| Multi Family Delivery Units: | 242Source: USPS |
| # of Businesses: | 2,325Source: CBP |
| 1st Quarter Payroll: | $341,661,000Source: CBP |
| Annual Payroll: | $1,345,373,000Source: CBP |
| # of Employees: | 21,957Source: CBP |
ZIP Code 91789 is located in Los Angeles County, California, within the Los Angeles-Long Beach-Anaheim, CA Metropolitan Statistical Area (CBSA 31080) and California's 31st, 35th, and 38th Congressional Districts. This Metro area has a population of 13,012,469 people, about 0.32% of whom live in ZIP Code 91789, and is subdivided into the Los Angeles-Long Beach-Glendale, CA division. It covers 15.867 sq mi of land and a water area of 0.051 sq mi.
| CBSA Name: | Los Angeles-Long Beach-Anaheim, CASource: Census |
| CBSA Number: | 31080Source: Census |
| CBSA Type: | MetroSource: Census |
| CBSA Division: | Los Angeles-Long Beach-Glendale, CA (CBSA Div 31084)Source: Census |
| CBSA Population: | 13,012,469Source: Census |
| MSA: | Los Angeles-Riverside-Orange County, CASource: Census |
| Land Area: | 15.867 sq miSource: Census |
| Water Area: | 0.051 sq miSource: Census |
| Congressional District: | 31,35,38Source: USPS |
| Congressional Land Area: | 218.24, 168.88, 101.46 sq miSource: Census |
| PMSA: | Los Angeles-Long Beach, CA PMSASource: Census |
| Intro Date: | < 2004-10Source: ZIP-Codes.com |
| Place FIPS Code: | 0683332Source: Census |
| Place Name: | Walnut city; CaliforniaSource: Census |
ZIP Code 91789 is part of 2 school districts, including: Rowland Unified School District (Grades KG thru 12) and Walnut Valley Unified School District (Grades Kindergarten thru 12th). There are 11 public schools and 4 private school(s) in this ZIP Code. It also has 6 colleges, universities or post secondary education institutions nearby which would be a short commute to.
Our sources include trusted federal and licensed data from the United States Postal Service, U.S. Census Bureau, U.S. Geological Survey, Centers for Medicare & Medicaid Services, and the National Center for Education Statistics, along with proprietary datasets created by ZIP-Codes.com. Data last updated on October 1, 2025.