91789 ZIP Code — Walnut, CA

Los Angeles County, California

ZIP code 91789 is located in Walnut, California, within Los Angeles County. It covers approximately 15.87 square miles and serves a population of 41,377 residents. This is a standard ZIP code in the Pacific (PT) timezone, served by area code 909.

About ZIP code 91789

The housing stock consists of predominantly single-family detached homes. Most homes were built in the 1980s, giving the area an established character. Median home value is $910,400. Owner-occupancy is high at 82%, well above the national average.

The gap between median ($123,555) and mean household income suggests income inequality — a small number of higher earners pull the average up. The poverty rate of 7% is below the national average. 37% of households receive Social Security income, suggesting a notable retiree or disability population.

The dominant occupation class is management, business, and professional, with education and healthcare as the leading industry. An above-average commute of 36 minutes suggests many residents work outside the immediate area.

Educational attainment is high — 53% of residents hold a bachelor's degree or higher, well above the national average of 33%.

Notable community characteristics include Spanish spoken in 31% of households.

Overall, ZIP code 91789 reflects a community defined by a highly educated population, high homeownership, and a significant Social Security-dependent population.

41,377

population

15.87

sq mi land

Standard

ZIP type

Pacific (PT)

timezone

91789 ZIP code map

Cities in ZIP code 91789

Below are the cities the US Postal Service accepts for ZIP code 91789. Using any city not on this list may result in mail delivery delays.

City	Status
Walnut	Acceptable
Walnut	Acceptable
Walnut	Preferred

Nearby ZIP codes

91765 Diamond Bar (2.4 mi) 91792 West Covina (2.6 mi) 91748 Rowland Heights (3.6 mi) 91791 West Covina (3.9 mi) 91724 Covina (4.6 mi) 91744 La Puente (4.7 mi) 91768 Pomona (5 mi) 91723 Covina (5.3 mi) 91766 Pomona (5.6 mi) 92821 Brea (6.2 mi) 91790 West Covina (6.4 mi) 91722 Covina (6.5 mi)

Demographics updated 07/2026

Population
Total population	41,377
Population density	2,607 / sq mi
State FIPS	06
County FIPS	037

Geography
Land area	15.87 sq mi
Water area	0.05 sq mi
Latitude	34.0130
Longitude	-117.8539
Timezone	Pacific (PT)
Area code	909

Total population by age

Gender

Race & ethnicity

Economics updated 07/2026

Household income

Income range	This ZIP	County avg	State avg
Under $50k	21.0%	36.2%	32.6%
$50k – $100k	26.8%	28.2%	27.7%
$100k – $200k	35.2%	24.5%	26.4%
Over $200k	16.9%	11.0%	13.3%

Demographics & statistics

41,377

Population

2,607

People per sq mi

46.1

Median age

$123,555

Median household income

$48,176

Per capita income

$910,400

Median home value

$2,690

Median monthly rent

82.0%

Home ownership

7.2%

Poverty rate

4.6%

Unemployment

11,246

Housing units

53.2%

Bachelor's or higher

Age distribution

Male Female

880

Under 5

918

1,015

5–9

1,058

1,279

10–14

1,333

979

15–19

1,020

1,163

20–24

1,212

2,387

25–34

2,490

2,181

35–44

2,275

2,564

45–54

2,673

1,699

55–59

1,771

1,714

60–64

1,787

2,856

65–74

2,978

1,227

75–84

1,280

312

85+

326

← Male

Female →

Age summary

Group	Count	%
Under 18	7,779	18.8%
18 and over	33,598	81.2%
65 and over	8,979	21.7%
Median age	46.1 years

Race & ethnicity

Asian 58.2%

White 14.5%

Hispanic or Latino 10.9%

Other race 7.1%

Two or more races 6.5%

Black or African American 2.1%

Native Hawaiian / Pacific Islander 0.5%

American Indian / Alaska Native 0.2%

Group	Count	%
Asian	27,014	58.2%
White	6,742	14.5%
Hispanic or Latino	5,049	10.9%
Other race	3,297	7.1%
Two or more races	3,011	6.5%
Black or African American	995	2.1%
Native Hawaiian / Pacific Islander	224	0.5%
American Indian / Alaska Native	94	0.2%

Household income

Income range	This ZIP	County avg	State avg
Under $50k	21.0%	36.2%	32.6%
$50k – $100k	26.8%	28.2%	27.7%
$100k – $200k	35.2%	24.5%	26.4%
Over $200k	16.9%	11.0%	13.3%

Under $10k 4.6%

$10k–$15k 0.7%

$15k–$25k 3.3%

$25k–$35k 3.9%

$35k–$50k 4.7%

$50k–$75k 11.9%

$75k–$100k 11.2%

$100k–$150k 21.1%

$150k–$200k 14.6%

$200k+ 23.9%

Range	% of households
Under $10k	4.6%
$10k–$15k	0.7%
$15k–$25k	3.3%
$25k–$35k	3.9%
$35k–$50k	4.7%
$50k–$75k	11.9%
$75k–$100k	11.2%
$100k–$150k	21.1%
$150k–$200k	14.6%
$200k+	23.9%
Median income	$123,555

Housing

Home values

Under $50k 0.9%

$50k–$100k 2.6%

$100k–$150k 1.2%

$150k–$200k 1.4%

$200k–$300k 0.4%

$300k–$500k 3.0%

$500k–$1M 54.8%

$1M+ 35.6%

Housing overview

Metric	Value
Median home value	$910,400
Median rent / month	$2,690
Owner occupied	82.0%
Renter occupied	18.0%
Vacant	6.2%
Single-family detached	87.1%
Large apartment buildings	2.2%
Mobile homes	3.7%
Median rooms	6.5
Avg household size (owned)	3.16

Year built

Era	%
2020 or later	0.0%
2010–2019	1.8%
2000–2009	3.8%
1990–1999	6.4%
1980–1989	46.1%
1970–1979	24.4%
1960–1969	13.8%
1950–1959	2.6%
1940–1949	0.2%
1939 or earlier	0.9%

Bedrooms

Size	% of units
No bedroom (studio)	0.5%
1 bedroom	0.8%
2 bedrooms	7.7%
3 bedrooms	31.4%
4 bedrooms	46.8%
5+ bedrooms	12.8%

Vehicles per household

Vehicles	% of households
No vehicle	1.8%
1 vehicle	14.8%
2 vehicles	40.3%
3 or more	43.1%

Heating fuel

Fuel type	%
Utility gas	82.2%
Electricity	15.1%
Propane / LP gas	1.4%
Wood	0.2%
Solar	0.5%
No fuel used	0.5%

Households & families

Household type	Count	%
Married-couple family	8,826	69.5%
Cohabiting couple	328	2.6%
Male householder, no spouse	1,225	9.6%
Female householder, no spouse	2,319	18.3%
Households with children under 18	4,092	32.2%
Households with seniors (65+)	5,596	44.1%
Average household size	3.25

Marital status

Status	Male	Female
Never married	33.0%	25.9%
Married	60.7%	59.4%
Separated	0.8%	1.2%
Widowed	2.4%	6.3%
Divorced	3.1%	7.2%

Education

Less than 9th grade 4.2%

Some HS, no diploma 3.0%

HS graduate 15.4%

Some college, no degree 15.4%

Associate's degree 8.8%

Bachelor's degree 36.1%

Graduate / professional 17.1%

Metric	%
HS diploma or higher	92.8%
Bachelor's or higher	53.2%

School enrollment (ages 3–17)

Type	Count	%
Nursery / preschool	424	4.3%
Kindergarten	651	6.6%
Elementary school	3,499	35.6%
High school	1,730	17.6%
College / grad school	3,514	35.8%

Employment

Industry of employment

Education & healthcare 22.4%

Professional & management 12.1%

Retail trade 11.4%

Finance & real estate 9.5%

Arts, food & hospitality 8.3%

Manufacturing 8.1%

Wholesale trade 6.7%

Transportation & utilities 6.6%

Public administration 5.3%

Other services 4.0%

Construction 3.9%

Information 1.4%

Agriculture & mining 0.4%

Occupation

Category	%
Management, business & arts	52.1%
Service	11.5%
Sales & office	24.1%
Natural resources & construction	3.5%
Production & transportation	8.8%

Employment type

Type	%
Private sector	77.6%
Government	15.3%
Self-employed	6.8%
Unpaid family workers	0.3%

Commute

Method	%
Drive alone	71.2%
Carpool	9.0%
Public transit	2.0%
Walk	0.4%
Work from home	15.5%
Other means	1.8%
Avg commute (minutes)	35.6

Poverty

All people 7.2%

Under 18 years 8.1%

18 and over 7.0%

Married-couple families 5.5%

Female-led households 8.6%

Income support

Source	% of households
Social Security	37.3%
Retirement income	25.5%
Supplemental Security	4.3%
Cash public assistance	2.7%
Food stamps / SNAP	4.8%

Health indicators

Condition	%
Obesity	18.8%
High blood pressure	25.4%
High cholesterol	30.5%
Diabetes	9.5%
Heart disease	4.2%
Stroke	2.1%
Asthma	6.7%
Arthritis	15.0%
Kidney disease	2.2%
Pulmonary disease	3.4%
Cancer	4.6%

Behavior / access	%
Smoking	6.9%
Binge drinking	12.7%
No physical activity	17.5%
Less than 7 hrs sleep	31.3%
Depression	11.3%
Fair or poor health	10.2%
Poor mental health	10.9%
Poor physical health	6.9%
No health insurance	9.1%
Visited doctor (checkup)	65.7%
Visited dentist	68.1%
Cholesterol screening	92.9%
Teeth loss	5.9%

Veterans & disability

Veterans	Count	%
Civilian veterans	1,169	3.5%

Disability	%
Any disability	7.8%
Under 18	2.1%
18–64 years	5.0%
65 and over	20.7%

Health insurance coverage

Type	%
Private insurance	71.3%
Public insurance	32.9%
No insurance	4.9%
Uninsured under 19	3.5%

Language & origin

Language spoken at home (age 5+)

Language	Count	%
English only	39,579	95.7%
Spanish	12,435	31.4%
Other Indo-European	926	2.3%
Asian & Pacific Islander	364	0.9%
Other languages	11,107	28.1%

Place of birth & citizenship

Origin	Count	%
Native born (US)	21,223	51.3%
Born in same state	20,611	49.8%
Born in different state	17,662	42.7%
Foreign born	612	1.5%
Naturalized citizen	20,154	48.7%
Not a US citizen	14,804	73.5%

Ancestry

Ancestry	Count	%
French	1,038	2.5%
Arab	821	2%
Italian	580	1.4%
Norwegian	151	0.4%
German	72	0.2%

Ancestry	Count	%
Irish	67	0.2%
English	41	0.1%
Polish	40	0.1%
Dutch	25	0.1%

Technology access

Metric	% of households
Computer access	30.7%
Internet access	98.2%

Source: U.S. Census Bureau, American Community Survey 2025 estimates.

Frequently asked questions about ZIP code 91789

What city is ZIP code 91789 in?

ZIP code 91789 is primarily assigned to Walnut, California.

What county is ZIP code 91789 in?

ZIP code 91789 falls within Los Angeles County, California.

Is Spanish widely spoken in ZIP code 91789?

Approximately 31% of households in ZIP code 91789 speak Spanish as a primary language.

How educated is the population of ZIP code 91789?

53% of residents hold a bachelor's degree or higher — well above the national average of ~33%, reflecting a highly educated population.

Is ZIP code 91789 mostly owner-occupied?

82% of occupied units in ZIP code 91789 are owner-occupied, well above the national average.

Does ZIP code 91789 have a large retiree population?

37% of households in ZIP code 91789 receive Social Security income, suggesting a significant retiree or disability population.

What timezone is ZIP code 91789 in?

ZIP code 91789 observes the PST timezone.