Diamond Bar Population

1970–2026

51,204

2026 projection

7% since 2020 (decrease)

010K20K30K40K50K60K197019801990200020102020

Source: U.S. Census Bureau decennial counts and annual estimates, including 2010–2020 intercensal estimates. 2026 is a projection. Values between recorded years are interpolated.

Use the left and right arrow keys to inspect population observations.

Population by year

Population estimates for Diamond Bar. Annual change is shown as a percentage. Growth is the total change since the preceding observation.
202651,204-6801.31%
202551,884-4040.77%
202452,288-2510.48%
202352,539-4970.94%
202253,036-8111.51%
202153,847-1,2252.22%
202055,072-4150.75%
201955,487-5410.97%
201856,028-3680.65%
201756,396-1710.30%

Showing 10 of 21 years.

The 2020 row compares the April 1 Census count with the July 1, 2019 estimate (about nine months). Its Growth and Annual change therefore do not represent a full year.

Growth since 2020, compared

Diamond Bar has a population change lower than Los Angeles County, California, and the U.S.

  • United States+3.1%
  • California−0.4%
  • Los Angeles County−3.0%
  • Diamond Bar−5.7%

Change from July 1, 2020 to July 1, 2025 population estimates—not annualized growth or site projections.

Source: U.S. Census Bureau. U.S. totals are summed from the 50 states and D.C.; unavailable comparisons are omitted.

Diamond Bar Demographics

45.7median age

Median age

Female45.8 yrs
Male45.5 yrs

Adults

43,229
11,217 seniors (65+) · 26% of adults32,012 other adults

Sex

Female 52.5% · 28,031Male 47.5% · 25,324

Population by age

MaleFemale85+ years, male: 52585+ years, female: 69280–84 years, male: 57880–84 years, female: 58475–79 years, male: 95775–79 years, female: 1,13170–74 years, male: 1,38370–74 years, female: 1,66265–69 years, male: 1,78065–69 years, female: 1,92560–64 years, male: 1,62860–64 years, female: 2,29255–59 years, male: 1,95955–59 years, female: 2,17350–54 years, male: 2,25250–54 years, female: 2,03145–49 years, male: 1,84545–49 years, female: 1,95140–44 years, male: 1,43840–44 years, female: 1,83235–39 years, male: 1,30735–39 years, female: 1,35930–34 years, male: 1,78530–34 years, female: 1,72225–29 years, male: 1,45825–29 years, female: 1,52720–24 years, male: 1,14120–24 years, female: 1,20115–19 years, male: 1,61415–19 years, female: 1,56210–14 years, male: 1,61810–14 years, female: 1,7875–9 years, male: 1,0865–9 years, female: 1,6740–4 years, male: 9700–4 years, female: 92685+80–8475–7970–7465–6960–6455–5950–5445–4940–4435–3930–3425–2920–2415–1910–145–90–41K1K2K2K

Hover or tap an age group to see exact counts. Use the up and down arrow keys to inspect age groups.

U.S. Census Bureau, 2024 ACS 5-year estimates · Table S0101

Race and ethnicity

Tap a square or a group below to highlight it.

Each square is about 1% of residents (roughly 534 people).

Hispanic or Latino residents can be of any race. All other groups exclude Hispanic residents.

U.S. Census Bureau, 2024 ACS 5-year estimates · Table B03002

Diamond Bar Income

$108,281median household income

Median household income

$108,281

Half of households earn more, half earn less

Median earnings

$61,878

Typical yearly pay for a worker 25 or older.

Poverty rate

10%

About 1 in 10 residents

U.S. Census Bureau, 2024 ACS 5-year estimates · Tables S1901, S1501, S1701

Diamond Bar Marital Status

56% of residents age 15 and older are married.

MarriedNever married
Overall
Male
Female
Marital status of residents age 15 and older
StatusOverallMaleFemale
Married56%58%53%
Never married31%34%28%
Divorced7%5%10%
Widowed6%3%8%
Separated1%<1%2%

U.S. Census Bureau, 2024 ACS 5-year estimates · Table S1201

Sources

14 sources

Population

American Community Survey, 2024 5-year

Additional sources