Cougars Mural Darrah, 2013
Diamond Bar’s story
56 years in pictures
Census counts: 10,576 in 1970, 55,072 in 2020. The archive holds 5 old photos and papers going back to 2013 and 7 maps from 1894 on.
- 1970Diamond Bar is settled
Diamond BarCA
A city of 51,884, settled in 1970.
4 bordering townsMap →
Photo: Thebluewriter · CC BY-SA 4.0
Population
51,884
2025 Census estimate · −6% since 2020
Typical home
$1M
+1.3% in a year
Household income
$108K
median
Median age
45.7
years
Jobs based here
17,655
Balanced
TownGrade
B−
#224 of 841 in CA
Is Diamond Bar a good place to live?
Homes are expensive, about $1.0 million for a typical one and 10.5 times the Los Angeles metro’s $96K median household income. Overall it grades B−, 224th of 841 graded towns in California. CDC estimates put its residents' health ahead of 86% of the country and the median household earns $108K. Its weakest subject is hazard risk: FEMA rates its natural-hazard risk higher than 85% of U.S. communities, with earthquakes at the top. Diamond Bar’s median rent is $2,521 a month, where California’s towns sit at $1,895 a month and U.S. towns at $1,185 a month. On history, just 19 of California’s 1,063 towns do worse. The biggest park or preserve is Tres Hermanos Ranch, at 594 acres.
What makes Diamond Bar stand out
Where Diamond Bar beats most towns, and one thing worth knowing.
32 measures vs. California
24 better6 too close to call2 worse
| Widest gap | Diamond Bar | CA |
|---|---|---|
| Fewer uninsured adults | 5.5% | 10.6% |
HealthA
Beats CA on 24 of 32 CDC measures, trails it on 2
Less healthyHealthier
CDC PLACES 2025 estimates.
WalkabilityB+
More walkable than 73% of U.S. towns
1.7% of workers walk, bike or ride transit
EPA National Walkability Index; Census ACS.
Worth knowing · Natural hazardsD
Earthquakes and inland flooding at the top
FEMA National Risk Index.
How Diamond Bar grades
Each subject compared with towns across the country (schools within California), ordered by how far Diamond Bar is from typical.
Its grades run from A for health (better than 86% of comparable towns) to D− for cost of living (better than 1%), so the B− overall blends very different results.
Cost of livingD−Open →Hazard riskearthquakes tops the listDOpen →HealthPomona Valley Hospital Medical Center 6.5 miles awayAOpen →Jobs & incomeA−Open →WalkabilityEPA walkability 10.9 of 20; 2.4% of households have no carB+Open →SchoolsB+Open →SafetyC+Open →
Character Graded, but not part of the overall grade.
Outdoors4% conserved landB−Open →History9 notable people born hereD−Open →Civic life3 community nonprofits per 1,000 residentsDOpen →
Described, not graded Taste, not quality: snow or an older crowd is neither good nor bad.
ClimateMild winters, 91° summer afternoons–Open →Housing market48 days on market–Open →Who lives hereMedian age 45.7; 53% of adults have a four-year degree–Open →
How TownRatings grades towns →
Nearby attractions
All 277 attractions →Disneyland and 242 more within 40 miles
Museums, parks, gardens and other places to visit around Diamond Bar. Close and well known come first.
Big draw15 mi Theme parkDisneyland17.3M visitors a year
Big draw30 mi Stadium & arenaSoFi Stadium
Big draw31 mi LandmarkHollywood Walk of Fame10.0M visitors a year
Big draw27 mi MuseumLucas Museum of Narrative Art
Big draw15 mi Theme parkKnott's Berry Farm4.5M visitors a year
Big draw27 mi Stadium & arenaLos Angeles Memorial ColiseumSources: National Park Service · ski areas © OpenSkiMap / OpenStreetMap contributors · Wikidata · Wikipedia readership · photos via Wikimedia Commons
Photo credits
Disneyland: HarshLight from San Jose, CA, USA, CC BY 2.0 · SoFi Stadium: Thank You (21 Millions+) views, CC BY 2.0 · Hollywood Walk of Fame: BenSherman, Public domain · Lucas Museum of Narrative Art: Kriddl, CC0 · Knott's Berry Farm: Phydend at English Wikipedia, Public domain · Los Angeles Memorial Coliseum: CanonStarGal, CC BY-SA 4.0
Getting set up
The full setup list →Moving to Diamond Bar: who provides what
Who provides power, water and the rest in Diamond Bar, and how to reach them.
PowerSouthern California Edison31.5¢/kWh · EIA 2025HIFLD · EIA
WaterThree Valleys Mwd water systemNo health-based violations in 5 years · EPAEPA
Internet5 providers99% of addresses get 100/20 MbpsFCC
Trash & dumpNearest public drop-offOlinda Alpha Landfill, 4 miOpenStreetMap
SchoolsWalnut Valley Unified School DistrictPomona Unified School District2 districts serve Diamond Bar; which school depends on your address and gradeNCES
Register to voteOnlineIn California you can register online until 15 days before Election Day, in person up to and including Election Day, or by mail (postmarked 15 days before).vote.govWho runs elections hereLos Angeles Registrar-Recorder County ClerkLos Angeles County; contacts on the Handbook page.FVAP, Sep 2025
ZIP codes91765, 9178991765 84% · 91789 16%Census 2020
EPA SDWIS (Oct 9, 2026) · HIFLD + EIA-861 2025 · Census 2020 ZCTAs · NCES 2024–25 · registration: vote.gov, updated Nov 18, 2024.
The data
Ordered by what stands out in Diamond Bar.
Diamond Bar has milder winter nights than nearly all U.S. towns and has less no health insurance than most of California, but it has homes that cost more against local pay than most of California.
HealthA
Compared with most of California and the rest of the country, fewer of Diamond Bar’s adults have obesity
Its widest gap with California is no health insurance: 5.5% of those 18–64 have no health insurance, against 10.6% statewide.
18% of Diamond Bar adults have obesity. Among 847 California towns, just 10 have a lower share of adults who have been diagnosed with depression than Diamond Bar. 30% of Diamond Bar adults have high blood pressure.
86%healthier than U.S. townsAHealth Grade
| Diamond Bar | California towns | U.S. towns | |
|---|---|---|---|
| Obesity (CDC PLACES) | 18% | 29% | 35% |
| Depression (CDC PLACES) | 15% | 22% | 23% |
| Binge drink (CDC PLACES) | 12% | 16% | 16% |
| Frequent mental distress (CDC PLACES) | 12% | 17% | 17% |
32 measures vs. California
24 better6 too close to call2 worse
| What stands out | Diamond Bar | CA |
|---|---|---|
| Fewer uninsured adults | 5.5% | 10.6% |
| Fewer adults facing a utility shut-off | 4% | 7.3% |
| More adults with high cholesterol | 40.2% | 35.4% |
Pomona Valley Hospital Medical Center
6.5 mi away · emergency room
None
primary care, dental or mental-health shortage
77th
percentile among CA towns
CDC PLACES 2025 · modeled estimates for adults · CMS · HRSA
SchoolsB+
Diamond Bar’s schools rank ahead of 72% of California districts
Its public schools are run by the Walnut Valley Unified school district. Two of its 17 schools are below, each with why it’s listed.
72%of CA districts it outscoresB+School Grade
| School | Level | Students | Letter |
|---|---|---|---|
| Chaparral MiddleLargest public middle schoolGrades 6–8 | Grades 6–8 | 1,349 | – |
| Diamond Bar HighLargest public high schoolGrades 9–12 | Grades 9–12 | 2,563 | A+ |
NCES · EDFacts · graded within CA on state tests and graduation
Natural hazardsHazard risk grade D
Very high risk in Diamond Bar, with earthquakes at the top
One flood insurance claim has been paid in Diamond Bar since 1998.
85risk score of 100
FEMA risk score
EarthquakesInland floodingWildfire
1
paid flood claims since 1998
6
federal disasters paid out here
FEMA flood insurance claims · FEMA National Risk Index · OpenFEMA
HousingCost of living grade D−
Diamond Bar’s grade for cost of living is a D−
At 10.5 years of the Los Angeles metro’s $96K median household income, the typical home (about $1M) costs more against local pay than in 79% of California towns; that ratio is one input to its D− for cost of living.
The typical Diamond Bar home is worth about $1,004,000, up 1.3% in a year, 32% above the California typical home. 77% of households own their home in Diamond Bar.
$1MZillow home value
Typical home value
Diamond Bar$1M
California$762K
Market temperature
48
days on market
99.8%
sale-to-list price
+1.3%
value change, 1 year
39
homes sold in May
Census ACS, 2020–24 · Zillow Home Value Index · Redfin Data Center
Climate
Mild winters and hot summers in Diamond Bar
January nights average 45°, milder than in 97% of U.S. towns; July afternoons average 89.2°.
Diamond Bar has warm winters and warm summers, with very little rain. Diamond Bar’s January low is 45°F. Snow is almost unheard of.
91°summer high
| Diamond Bar | California towns | U.S. towns | |
|---|---|---|---|
| January low | 45°F | 40°F | 22°F |
| July high | 89°F | 89°F | 85°F |
Typical low → high °F
Winter45–68°
Spring51–74°
Summer61–88°
Fall56–81°
+2.7°
vs. the 20th-century average
91°
typical summer high
NOAA U.S. Climate Normals, 1991–2020
Work & commuteJobs & income grade A−
Diamond Bar has 0.8 jobs for every working resident, so most commute out
Most working residents leave Diamond Bar for work: only 8% work in town. The average trip to work in Diamond Bar is 33 minutes. Since 2013, Diamond Bar has added 2,346 jobs, to 17,655 in 2023.
8%work in town
| Diamond Bar | California towns | U.S. towns | |
|---|---|---|---|
| Average trip to work | 33 minutes | 28 minutes | 25 minutes |
| Work from home | 18% | 14% | 11% |
| Median household income | $108,000 | $95,000 | $80,000 |
Where working residents work
In Diamond Bar8%
Los Angeles12%
Industry6%
Anaheim4%
Pomona4%
15 mi
median commute distance
17,655
jobs based in Diamond Bar
Balanced
jobs vs. working residents
B+
Walkability grade: more walkable than 73% of U.S. towns
Census LEHD 2023 · ACS
#543for trails in CA
| Diamond Bar | California towns | U.S. towns | |
|---|---|---|---|
| Miles of trail per square mile | 0.5 miles per square mile | 1.0 | 0.4 |
| Conserved land | 4.3% | 4.2% | 4.3% |
4.3%
conserved · 403 of 9,487 acres
7.0 mi
of trails · 0.5 per sq mi
| Biggest places to walk | Trails | Acres |
|---|---|---|
| 1. Sycamore Canyon Park | 0.8 mi | 48 |
| 2. Diamond Canyon Park | 0.7 mi | 4 |
| 3. Tres Hermanos Ranch | 0.2 mi | 594 |
Trails & parks © OpenStreetMap contributors · Conserved land: USGS PAD-US
SafetyC+
Diamond Bar sees more crime per resident than 59% of U.S. towns
Reported crimes fell from 1,072 to 908 over the last three FBI years, a drop beyond ordinary year-to-year swings.
Within California, it does better than 71% of towns.
41%of U.S. towns report more crimeC+Safety Grade
| Diamond Bar | California towns | U.S. towns | |
|---|---|---|---|
| Property crimes per 1,000 (2025) | 16.3 per 1,000 residents | 13.3 | 9.9 |
| Violent crimes per 1,000 (2025) | 1.2 per 1,000 residents | 2.9 | 1.6 |
Violent crime per 1,000 residents
Diamond Bar1.2
California4.3
U.S.3.3
Property crime per 1,000 residents
Diamond Bar16.3
California18.2
U.S.15.5
41st
percentile among U.S. towns we grade
71st
percentile among CA towns
64
violent crimes reported in 2025
844
property crimes reported in 2025
FBI crime data, 2025 · crimes reported to police
Keep exploring
Everything we know about Diamond Bar
20pages on Diamond Bar
The big questions
SchoolsB+Beat 72% of CA districts · 17 schoolsSafetyC+1.2 violent crimes per 1,000 residents (2025)HealthABetter than CA on 24 of 32 CDC measuresCost of livingD−$1M typical home · up 1.3% in a yearWork & commuteA−$108K median household income · 17,655 jobs hereNatural hazardsDFEMA risk higher than 85% of U.S. communities · earthquakes
Out and about
The story
After high school
Colleges nearby
40 within 15 miles of the center of Diamond Bar
Mt San Antonio CollegeCommunity college · Public · Walnut3.6 mi$1,364 in-state tuitionCalifornia State Polytechnic University-PomonaUniversity or college · Public · Pomona3.9 mi$7,780 in-state tuitionWestern University of Health SciencesUniversity or college · Private nonprofit · Pomona5.6 mi
About 9 of every 100 Diamond Bar residents are enrolled in college, about the same as California.
Famous people from Diamond Bar
9 notable people were born in Diamond Bar.
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About Diamond Bar
City in Los Angeles County, California, US
Diamond Bar is a city in the San Gabriel Valley of eastern Los Angeles County, California, United States. The 2020 census listed a population of 55,072. It is named after the "diamond over a bar" branding iron registered in 1918 by ranch owner Frederic E. Lewis (1884–1963). The city features a public Los Angeles County golf course. Located at the junction of the Pomona and Orange freeways, Diamond Bar is primarily residential with shopping centers interspersed throughout the city. It is surrounded by the cities of Brea, Walnut, Chino Hills, Pomona, City of Industry, and the unincorporated areas of Rowland Heights and South Diamond Bar. Northern Diamond Bar is a part of the Pomona Unified Sc…
From Wikipedia, licensed CC BY-SA 4.0 · facts via Wikidata (CC0)
- Established
- 1989
- Area
- 15 sq mi
- Elevation
- 696 ft
- ZIP code
- 91765
- Area code
- 909
Diamond Bar’s neighbors
4 towns share a border with Diamond Bar.
IndustryPomonaRowland HeightsChino HillsDiamond Bar
How the neighbors grade
| Town | CA rank | Overall | Cost | Safety | Schools | Health |
|---|---|---|---|---|---|---|
| Diamond Bar | #224 | B− | D− | C+ | B+ | A |
| Industry | — | — | — | — | — | — |
| Pomona | #671 | D | D | D | C+ | C+ |
| Rowland Heights | #306 | C+ | D− | — | B+ | B+ |
| Chino Hills | #165 | B | D− | — | A− | A |
Rowland Heights and Chino Hills report no FBI crime data of their own. Industry isn’t graded (fewer than 1,000 residents, or not enough data). Compare Diamond Bar with a neighbor →
Questions about Diamond Bar
Short answers, built from the data on this page.
Is Diamond Bar, CA a good place to live?
Diamond Bar grades B− overall, better than 48% of U.S. towns and #224 of 841 in California. It grades A for health, C+ for safety and B+ for schools. Cost of living is its weak spot, with a D−.
Is Diamond Bar, CA safe?
Within California, it does better than 71% of towns.
Is Diamond Bar, CA expensive?
Yes. Cost of living, which also weighs rents, property taxes and how many households pay 30% or more of their income for housing, grades D−.
What is Diamond Bar, CA known for?
9 notable people were born here, including Nadia Mejia and Ryan Wendell.