Where does this demographic data come from?

All demographic data comes from the U.S. Census Bureau's American Community Survey (ACS) 5-Year Estimates, which samples about 3.5 million households annually. The 5-year estimates provide the most reliable data for small geographies like municipalities.

What is the difference between Census data and ACS data?

The decennial Census (conducted every 10 years) is a full population count focusing on basic demographics. The ACS is an ongoing survey that collects detailed data on income, education, housing, commute patterns, and more. ACS data is updated annually but represents averages over a 5-year period.

How accurate is this data for small towns?

For smaller municipalities, ACS estimates have wider margins of error because fewer residents are sampled. The 5-year estimates reduce this uncertainty by averaging over a longer period. For towns under 5,000 people, treat specific numbers as approximations rather than precise counts.

Mill Creek, WA Population, Income & Demographics 2026

CSASeattle-Tacoma MSASeattle-Tacoma-Bellevue#23/78 Home Value

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Demographics — 2024 ACS 5-Year Estimatesi

Census

Populationi

20,956

Median Agei

39.3

Race & Ethnicityi

White

61.3%12,836

Asian

20.3%4,260

Hispanic/Latino

8.6%1,803

Two or More

5.4%1,127

Black

3.2%674

Native Hawaiian/Pacific Islander

1.1%221

American Indian/Alaska Native

0.2%35

Educational Attainment (Age 25+)i

GED/Alternative

1.3%194

High School Diploma

9.9%1,480

Some College (<1 yr)

6%898

Some College (1+ yr)

14.1%2,103

Associate's Degree

8.6%1,280

Bachelor's Degree

33.8%5,023

Master's Degree

18%2,686

Professional Degree

2.9%426

Doctorate

1.3%197

HS or Higher

96%

BA or Higher

56%

Graduate+

22.2%

Housingi

Median Home Valuei

$903,800

Median Renti

$2,249

Tenure

Owner-Occupied

59%5,124

Renter-Occupied

41%3,558

Total Units

9,224

Homeownership

59%

Vacancy Rate

5.9%

Home Values

Under $50K

0.6%33

$50K–$100K

0.7%34

$100K–$150K

0.7%34

$200K–$300K

0.5%26

$300K–$500K

5.3%273

$500K–$1M

56.9%2,915

$1M+

35.3%1,809

Rent Distribution

Under $500

$500–$750

$1,250–$1,500

147

$1,500–$2,000

922

$2,000+

2,370

Year Built

2020 or later

1%96

2010–2019

14.6%1,346

2000–2009

22.6%2,082

1990–1999

23.8%2,193

1980–1989

23.2%2,138

1970–1979

12.3%1,131

1960–1969

1.4%130

1950–1959

0.2%19

1940–1949

0.1%10

1939 or earlier

0.9%79

Heating Fuel

Utility Gas

56.8%4,932

Electricity

42.8%3,713

Bottled/LP Gas

0.4%37

Economyi

Median Household Incomei

$124,364

Mean Household Incomei

$164,650

Per Capita Incomei

$68,073

Poverty Ratei

6.4%

Unemploymenti

4.4%

Labor Forcei

11,874

Household Income Distribution

Under $10K

4%346

$10K–$15K

1.2%106

$15K–$20K

1.7%151

$20K–$25K

1.5%130

$25K–$30K

3.4%294

$30K–$35K

2.8%243

$35K–$40K

1.6%142

$40K–$45K

2.6%222

$45K–$50K

2.8%247

$50K–$60K

1.8%156

$60K–$75K

6%520

$75K–$100K

9.1%787

$100K–$125K

12%1,040

$125K–$150K

8.3%724

$150K–$200K

11.5%996

$200K+

29.7%2,578

Ancestry & Heritage

Self-reported ancestry groups. Residents may report multiple ancestries, so totals may exceed 100%.

Foreign-Born Populationi

Foreign-Borni

5,13224.5%

By Region

Top Countries

Korea

598

India

585

China

447

Mexico

361

United Kingdom

216

Philippines

175

Guatemala

Canada

Commute & Transportationi

Workersi

11,189

Avg. Commutei

33 min

How People Get to Work

Travel Time to Work

Workforce

Total Employed

11,151

Occupations

Industries

Social Characteristicsi

Marital Status (15+)i

Veteransi

817(5% of civilian adults)

Health Insurancei

96.9%Insured

3.1%Uninsured