Mountlake Terrace, WA

City in Snohomish County, WA, US

By Neilsberg Research

Last updated May 1, 2026

Key Indicators

A quick look at key numbers

Population

23,104

Source: U.S. Census Bureau American Community Survey (ACS) 2020-2024 5-Year Estimates

Median Age

38.3

years ∙ half population younger than 38.3, half older

Diversity Index

59.7%

chance two random people differ in race and ethnicity

Nativity

18.5%

foreign-born population

81.5%Native

18.5% Foreign-born

Geographic Context

Location, size, and surroundings

About

Mountlake Terrace is a city within Snohomish County, Washington, United States.

Location

City in Snohomish County, WA, US

Co-ordinates

DEC47.794329° N, 122.302607° W

DMS47° 47′ 39.58″ N, 122° 18′ 09.39″ W

Population Density & area

5,691/sq mi (2,200/km²)

Total Area

4.16 sq mi (10.77 km²)

Land Area

4.06 sq mi (10.5 km²) · 97.5%

Water Area

0.1 sq mi (0.27 km²) · 2.5%

Demographics & Living

Who lives here, how households are formed, and community composition

Population Composition

Key characteristics of the population

Sex Distribution

49.5% male

Male 49.5%

Female 50.5%

males per 100 females

Mountlake Terrace 97.8

Snohomish County 101.7

Washington 101.4

Nativity

18.5%

foreign-born population

81.5%Native

18.5% Foreign-born

% Foreign-born

Mountlake Terrace 18.5%

Snohomish County 19.3%

Washington 15.4%

Age Distribution

How the population is spread across age groups

Median Age

38.3

years ∙ half population younger than 38.3, half older

Mountlake Terrace

38.3

Snohomish County

38.6

Washington

38.3

Dependency ratio

50.3

dependents per 100 working-age adults

Mountlake Terrace 50.3

Snohomish County 58.5

Washington 61.3

AGE DISTRIBUTION

Distribution of age group

Median age

	Mountlake Terrace	Snohomish County	Washington
Age Group
Children (Under 18)	17%	22.1%	21.4%
Working age (18-64)	66.5%	63.1%	62%
Senior (65+)	16.5%	14.8%	16.6%
Dependency ratio
Total dependency ratio	50.3	58.5	61.3
Child dependency ratio	25.5	35.1	34.5
Old-age dependency ratio	24.8	23.4	26.8

Racial & Ethnic Composition

Racial and ethnic makeup and how it compares

Race & Ethnicity

White

59.8%

Black

4.2%

Asian

11.5%

Hispanic

15.3%

Other

9.2%

Note: White, Black, and Asian refer to individuals belonging to a single race and not of Hispanic origin. Hispanics may be of any race.

Diversity Index

59.7%

chance two random people differ in race and ethnicity

Mountlake Terrace 59.7%

Snohomish County 57.6%

Washington 56.5%

Note: The Diversity Index (DI), based on the Blau Index, measures the probability that two randomly selected individuals differ in race and ethnicity. Values range from 0 (no diversity) to 1 (high diversity) and are shown as percentages.

RACIAL & ETHNIC COMPOSITION

Race & Ethnicity

Percentage of Mountlake Terrace population

	Mountlake Terrace	Snohomish County	Washington
Hispanic or Latino	15.3%	12.1%	14.4%
Mexican	10.9%	8.4%	10.8%
Puerto Rican	0.2%	0.4%	0.5%
Cuban	0.1%	0.2%	0.2%
Other Hispanic / Latino	4.1%	3.1%	2.8%
Not Hispanic or Latino	84.7%	87.9%	85.6%
One race	76.6%	81%	78.8%
White	59.8%	62%	63.1%
Black or African American	4.2%	3.6%	3.8%
American Indian and Alaska Native	0.4%	0.6%	0.8%
Asian	11.5%	13.6%	9.7%
Native Hawaiian and Other Pacific Islander	0.3%	0.5%	0.7%
Some Other Race	0.4%	0.7%	0.6%
Two or more races (Multiracial)	8.1%	6.9%	6.8%

Household & Families Composition

Household size, type, and family structure

Household structure

57.4% family

Family 57.4%

Non family 42.6%

% family households

Mountlake Terrace 57.4%

Snohomish County 67.7%

Washington 63.4%

Average household size

2.32

persons per household

Mountlake Terrace

2.32

Snohomish County

2.64

Washington

2.5

Household & Family COMPOSITION

Households

Percentage of Mountlake Terrace population

	Mountlake Terrace	Snohomish County	Washington
Total households	9,855	316,212	3,064,820
Average houshold size	2.32	2.64	2.5
Family households	5,653	214,187	1,942,412
Average family size	2.93	3.15	3.07
Married couple family	4,124	169,330	1,506,003
Other families	1,529	44,857	436,409
Male householder	707	15,383	145,719
Female householder	822	29,474	290,690
Non-family households	4,202	102,025	1,122,408
One-person households	2,988	75,533	848,664
Male householder	1,167	35,405	404,881
Senior (65+) living alone	454	10,365	115,764
Female householder	1,821	40,128	443,783
Senior (65+) living alone	825	20,490	213,754
Other living arrangements	1,214	26,492	273,744

Housing Profile

Housing stock, ownership, rentals, and cost burdens

Total housing units

10,210

housing units

Mountlake Terrace 10,210

Snohomish County 331,530

Washington 3,306,620

Occupancy status

96.5% occupied

Occupied 96.5%

Vacant 3.5%

vacancy rate

Mountlake Terrace 3.5%

Snohomish County 4.6%

Washington 7.3%

Housing Characteristics

How the housing supply is structured and used

Types of Housing unit

55.4%

Single family houses

55.4%

Apartments in multi-unit structures

43.1%

Mobile homes

1.5%

Boat, RV, van, etc

Median Year Built

1973

Half of houses were built before 1973, and half after.

Historic ∙ 1939 or earlier

0.5%

Postwar & mid-century ∙ 1940 - 1969

45.6%

Late 20th century ∙ 1970 - 1999

38.3%

Modern ∙ 2000 or later

15.7%

Note: Median year built reflects occupied units only; distribution includes all units.

Housing Characteristics

Units, rooms & bedrooms

Physical characteristics of housing units

	Mountlake Terrace	Snohomish County	Washington
Rooms per unit
Median rooms	4.9	5.7	5.5
1–3 rooms	21.3%	14.9%	18.6%
4–6 rooms	55.6%	49%	47.6%
7+ rooms	22.9%	36.1%	33.8%
Bedrooms
No bedroom / studio	3.1%	2.6%	4.5%
1 bedroom	14.9%	8.9%	11.8%
2 bedrooms	32.8%	22.7%	24.3%
3 bedrooms	32%	38.2%	36.2%
4+ bedrooms	17.2%	27.6%	23.2%
At a glance
Median year built	1973	1990	1986
Total housing units	10,210	331,530	3,306,620

Occupancy Profile

Who is inside and how they use it

Homeownership

56.9% owners

Renter-occupied 43.1%

Owner-occupied 56.9%

homeownership rate

Mountlake Terrace 56.9%

Snohomish County 68.2%

Washington 63.8%

Average household size

2.43

Owner-occupied

2.19

Renter-occupied

owner-occupied average size

Mountlake Terrace 2.43

Snohomish County 2.72

Washington 2.65

Housing Characteristics

Occupied unit characteristics

Tenure, crowding, and utilities

	Mountlake Terrace	Snohomish County	Washington
Total occupied units	9,855	316,212	3,064,820
Year moved in
2020 or later	30.1%	26.5%	27.6%
2010 to 2019	37.8%	42.5%	41.8%
2000 to 2009	13.8%	15.9%	15.4%
1999 or earlier	18.3%	15%	15%
Occupants per room
1.00 or fewer	96.7%	96.3%	96.5%
1.01 to 1.50	2.4%	2.5%	2.2%
1.51 or more	0.8%	1.3%	1.4%
Vehicles availability
No vehicles	4.4%	4.7%	7.1%
1 vehicle	33.7%	27.9%	30.5%
2 vehicles	43.8%	38.6%	36.3%
3 or more vehicles	18.1%	28.8%	26.1%
House heating fuel used
Gas	33.9%	43.1%	36%
Electricity	63.6%	52.8%	58.6%
Solar	0%	0.1%	0.2%
Fuel oil, kerosene etc	1%	0.6%	1.3%
All other fuels	1.3%	2.7%	3.2%
No fuel used	0.1%	0.6%	0.6%
Selected characteristics
Lacking complete plumbing	0.8%	0.3%	0.4%
Lacking complete kitchen	1.1%	0.6%	1%
No telephone service available	0.6%	0.7%	0.8%

Housing Value

What owner-occupied units are worth

Median home value

$667,300

owner-occupied units

Median value(USD)

Mountlake Terrace

$667,300

Snohomish County

$696,000

Washington

$564,600

Housing Cost Burden

21.6%

of homeowners with a mortgage are cost-burdened

% Cost-Burdened Households

Owners with a mortgage

21.6%

Owners without a mortgage

17.9%

Renters

47.8%

Note: Households spending 30% or more of their income on housing costs are considered cost-burdened.

Financial characteristics

Property value and housing costs

Tenure, crowding, and utilities

	Mountlake Terrace	Snohomish County	Washington
Property value
Median Value	$667,300	$696,000	$564,600
Under $100,000	2.5%	3.6%	4.7%
$100,000 - $200,000	1.2%	1.9%	3.8%
$200,000 - $300,000	2%	2.6%	7%
$300,000 - $500,000	19.2%	16.3%	27.8%
$500,000 - $1,000,000	67.9%	57.6%	40.8%
$1,000,000 and more	7%	17.9%	15.9%
Owner-occupied households
With a mortgage	67.3%	71.9%	66.1%
Without a mortgage	32.7%	28.1%	33.9%
Median monthly owner costs
With a mortgage	$2,580	$2,748	$2,445
Without a mortgage	$829	$864	$773
Gross rent
Median rent	$2,004	$1,949	$1,760

Education Profile

How educated is the community and how education pays off

Adults with a college degree

43%

of adults 25+ with a bachelor's degree or higher

Mountlake Terrace 43%

Snohomish County 38.2%

Washington 39.6%

Adults without a high school diploma

5.7%

of adults (25+) without a high school diploma

Mountlake Terrace 5.7%

Snohomish County 6.9%

Washington 7.7%

School Enrollment

Who is enrolled in school and at what level

School enrollment

4,409

population (age 3+) enrolled in school

Nursery / Preschool

6.9%

K–12

68.5%

College / Undergraduate

18.4%

Graduate / Professional

6.2%

College-going rate (18-24 yr olds)

29%

of 18-24-year-olds in college or graduate school

Mountlake Terrace

29%

Snohomish County

28.4%

Washington

33.2%

Enrollment & school type

Enrollment levels, college-going rate, and public vs private school split

Population 3+ currently enrolled in a school

	Mountlake Terrace	Snohomish County	Washington
Total enrolled (age 3+)	4,409	186,557	1,763,756
Nursery / preschool	6.9%	6.3%	5.9%
K–12	68.5%	71.8%	69.1%
Kindergarten	2.6%	5.4%	5.1%
Elementary: Grades 1–4	25.4%	22.7%	20.9%
Elementary: Grades 5–8	22.3%	21.4%	21.4%
High School: Grades 9–12	18.2%	22.4%	21.6%
College or graduate school	24.6%	21.9%	25.1%
College, undergraduate	18.4%	17.1%	19.6%
Graduate, professional school	6.2%	4.8%	5.5%
College-going rate · 18-24 yr olds	29%	28.4%	33.2%
School type
Public school	87.8%	82.9%	83%
Private school	12.2%	17.1%	17%

Education Attainment by Level & Gender

What is the highest level of education completed among adults

Education attainment

17,563

population 25 years and over

Total adults (25+)

Less than 9th grade

2.3%

9th-12th, no diploma

3.4%

HS graduate

21.5%

Some college no degree

18.7%

Associates degree

11.2%

Bachelors degree

28.1%

Graduate or professional degree

14.9%

Attainment by gender

Male vs Female

Adults (25+) · Share within each education level

% male · % female

Less than 9th grade

53.2% · 46.8%

9th-12th, no diploma

59% · 41%

HS graduate

55.5% · 44.5%

Some college no degree

48% · 52%

Associates degree

46.8% · 53.2%

Bachelors degree

46.1% · 53.9%

Graduate or professional degree

38.7% · 61.3%

Educational Attainment Overview

Distribution and key education attainment rates for adults (25+)

Highest credential completed · adults 25+

	Mountlake Terrace	Snohomish County	Washington
Population (25+)	17,563	596,438	5,484,391
Less than 9th grade	2.3%	2.6%	3.4%
9th–12th, no diploma	3.4%	4.3%	4.3%
High school diploma or GED	21.5%	22.5%	21.6%
Some college, no degree	18.7%	21.8%	21%
Associate's degree	11.2%	10.5%	10%
Bachelor's degree or higher	43%	38.2%	39.6%
Bachelor's degree	28.1%	24.8%	24%
Graduate or professional	14.9%	13.4%	15.6%
High School or higher	94.3%	93.1%	92.3%

Earnings by education level

percentage as applicable

Median Earnings

$66,046

Median earnings for adults 25+, by level

Less than HS graduate

$48,313

HS graduate

$52,257

Some college or associates

$59,795

Bachelors degree

$85,187

Graduate or professional degree

$94,949

Poverty Rate

4.1%

for ages 25+, with bachelors degree or higher

Less than HS graduate

21.6%

HS graduate

10.9%

Some college or associates

6.9%

Bachelors degree or higher

4.1%

Outcomes by Education Level

Earnings and poverty rates across education levels (25+)

Adults 25+

	Mountlake Terrace	Snohomish County	Washington
Median earnings
Population 25+, with earnings	$66,046	$68,158	$62,378
Less than high school graduate	$48,313	$44,175	$37,363
High school graduate (includes equivalency)	$52,257	$51,690	$46,550
Some college or associate's degree	$59,795	$60,256	$53,700
Bachelor's degree	$85,187	$86,986	$81,898
Graduate or professional degree	$94,949	$114,652	$108,295
Poverty rates
Less than high school graduate	21.6%	18.6%	20.8%
High school graduate (includes equivalency)	10.9%	10.4%	12.2%
Some college or associate's degree	6.9%	7.4%	8.9%
Bachelor's degree or higher	4.1%	3.7%	4.2%

Insights for Mountlake Terrace, by topic

Income By year By race By age By gender

Population By year By race By age By gender

About Neilsberg Research

Neilsberg Research team are data scientists with expertise in processing, analysis and visualization of big data helping small businesses make right decisions.

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