Marietta-Alderwood, WA

Census-Designated Place in Whatcom County, WA, US

By Neilsberg Research

Last updated May 1, 2026

Key Indicators

A quick look at key numbers

Population

3,754

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

39.1%

chance two random people differ in race and ethnicity

Nativity

5.9%

foreign-born population

94.1%Native

5.9% Foreign-born

Geographic Context

Location, size, and surroundings

About

Marietta-Alderwood is an unincorporated community and census-designated place (CDP) in Whatcom County, Washington, United States.

Location

Census-Designated Place in Whatcom County, WA, US

Co-ordinates

DEC48.788096° N, 122.555162° W

DMS48° 47′ 17.15″ N, 122° 33′ 18.58″ W

Population Density & area

645/sq mi (249.3/km²)

Total Area

7.67 sq mi (19.85 km²)

Land Area

5.82 sq mi (15.06 km²) · 75.9%

Water Area

1.85 sq mi (4.79 km²) · 24.1%

Demographics & Living

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

Population Composition

Key characteristics of the population

Sex Distribution

54.5% male

Male 54.5%

Female 45.5%

males per 100 females

Marietta-Alderwood 119.9

Whatcom County 98.3

Washington 101.4

Nativity

5.9%

foreign-born population

94.1%Native

5.9% Foreign-born

% Foreign-born

Marietta-Alderwood 5.9%

Whatcom County 9.9%

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

Marietta-Alderwood

38.3

Whatcom County

38.4

Washington

38.3

Dependency ratio

62.6

dependents per 100 working-age adults

Marietta-Alderwood 62.6

Whatcom County 59.9

Washington 61.3

AGE DISTRIBUTION

Distribution of age group

Median age

	Marietta-Alderwood	Whatcom County	Washington
Age Group
Children (Under 18)	16.2%	18.5%	21.4%
Working age (18-64)	61.5%	62.6%	62%
Senior (65+)	22.3%	18.9%	16.6%
Dependency ratio
Total dependency ratio	62.6	59.9	61.3
Child dependency ratio	26.4	29.6	34.5
Old-age dependency ratio	36.2	30.2	26.8

Racial & Ethnic Composition

Racial and ethnic makeup and how it compares

Race & Ethnicity

White

76.8%

Black

0.2%

Asian

6.7%

Hispanic

2.9%

Other

13.4%

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

39.1%

chance two random people differ in race and ethnicity

Marietta-Alderwood 39.1%

Whatcom County 41%

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 Marietta-Alderwood population

	Marietta-Alderwood	Whatcom County	Washington
Hispanic or Latino	2.9%	10.6%	14.4%
Mexican	2.9%	7.4%	10.8%
Puerto Rican	0%	0.4%	0.5%
Cuban	0%	0.1%	0.2%
Other Hispanic / Latino	0%	2.7%	2.8%
Not Hispanic or Latino	97.1%	89.4%	85.6%
One race	85.6%	83.2%	78.8%
White	76.8%	75.7%	63.1%
Black or African American	0.2%	0.9%	3.8%
American Indian and Alaska Native	0.7%	1.6%	0.8%
Asian	6.7%	4.4%	9.7%
Native Hawaiian and Other Pacific Islander	1%	0.2%	0.7%
Some Other Race	0.2%	0.4%	0.6%
Two or more races (Multiracial)	11.5%	6.2%	6.8%

Household & Families Composition

Household size, type, and family structure

Household structure

61.1% family

Family 61.1%

Non family 38.9%

% family households

Marietta-Alderwood 61.1%

Whatcom County 58.8%

Washington 63.4%

Average household size

2.29

persons per household

Marietta-Alderwood

2.29

Whatcom County

2.4

Washington

2.5

Household & Family COMPOSITION

Households

Percentage of Marietta-Alderwood population

	Marietta-Alderwood	Whatcom County	Washington
Total households	1,638	94,021	3,064,820
Average houshold size	2.29	2.4	2.5
Family households	1,000	55,302	1,942,412
Average family size	2.63	2.94	3.07
Married couple family	710	44,587	1,506,003
Other families	290	10,715	436,409
Male householder	115	3,752	145,719
Female householder	175	6,963	290,690
Non-family households	638	38,719	1,122,408
One-person households	389	27,099	848,664
Male householder	253	11,991	404,881
Senior (65+) living alone	174	4,401	115,764
Female householder	136	15,108	443,783
Senior (65+) living alone	76	8,042	213,754
Other living arrangements	249	11,620	273,744

Housing Profile

Housing stock, ownership, rentals, and cost burdens

Total housing units

1,670

housing units

Marietta-Alderwood 1,670

Whatcom County 103,520

Washington 3,306,620

Occupancy status

98.1% occupied

Occupied 98.1%

Vacant 1.9%

vacancy rate

Marietta-Alderwood 1.9%

Whatcom County 9.2%

Washington 7.3%

Housing Characteristics

How the housing supply is structured and used

Types of Housing unit

52.9%

Single family houses

52.9%

Apartments in multi-unit structures

37.9%

Mobile homes

Boat, RV, van, etc

1.2%

Median Year Built

1981

Half of houses were built before 1981, and half after.

Historic ∙ 1939 or earlier

11.4%

Postwar & mid-century ∙ 1940 - 1969

14%

Late 20th century ∙ 1970 - 1999

52.1%

Modern ∙ 2000 or later

22.4%

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

Housing Characteristics

Units, rooms & bedrooms

Physical characteristics of housing units

	Marietta-Alderwood	Whatcom County	Washington
Rooms per unit
Median rooms	4.7	5.3	5.5
1–3 rooms	20.5%	18.2%	18.6%
4–6 rooms	49.2%	51.9%	47.6%
7+ rooms	30.4%	29.8%	33.8%
Bedrooms
No bedroom / studio	0%	4.8%	4.5%
1 bedroom	14.2%	10.1%	11.8%
2 bedrooms	39.2%	26.3%	24.3%
3 bedrooms	35.8%	40.2%	36.2%
4+ bedrooms	10.8%	18.6%	23.2%
At a glance
Median year built	1981	1989	1986
Total housing units	1,670	103,520	3,306,620

Occupancy Profile

Who is inside and how they use it

Homeownership

57.6% owners

Renter-occupied 42.4%

Owner-occupied 57.6%

homeownership rate

Marietta-Alderwood 57.6%

Whatcom County 63.7%

Washington 63.8%

Average household size

2.49

Owner-occupied

2.02

Renter-occupied

owner-occupied average size

Marietta-Alderwood 2.49

Whatcom County 2.53

Washington 2.65

Housing Characteristics

Occupied unit characteristics

Tenure, crowding, and utilities

	Marietta-Alderwood	Whatcom County	Washington
Total occupied units	1,638	94,021	3,064,820
Year moved in
2020 or later	25.3%	27.7%	27.6%
2010 to 2019	38.5%	41.5%	41.8%
2000 to 2009	16.2%	17.6%	15.4%
1999 or earlier	20%	13.3%	15%
Occupants per room
1.00 or fewer	95.4%	96.3%	96.5%
1.01 to 1.50	4.6%	2.5%	2.2%
1.51 or more	0%	1.1%	1.4%
Vehicles availability
No vehicles	3.3%	6.4%	7.1%
1 vehicle	28.7%	29.6%	30.5%
2 vehicles	39.3%	35.8%	36.3%
3 or more vehicles	28.7%	28.2%	26.1%
House heating fuel used
Gas	41.7%	48.2%	36%
Electricity	56.2%	46.5%	58.6%
Solar	0%	0.3%	0.2%
Fuel oil, kerosene etc	0%	0.9%	1.3%
All other fuels	2.1%	3.9%	3.2%
No fuel used	0%	0.4%	0.6%
Selected characteristics
Lacking complete plumbing	0%	0.5%	0.4%
Lacking complete kitchen	0%	1.3%	1%
No telephone service available	0%	0.7%	0.8%

Housing Value

What owner-occupied units are worth

Median home value

$547,100

owner-occupied units

Median value(USD)

Marietta-Alderwood

$547,100

Whatcom County

$585,800

Washington

$564,600

Housing Cost Burden

27.7%

of homeowners with a mortgage are cost-burdened

% Cost-Burdened Households

Owners with a mortgage

27.7%

Owners without a mortgage

12.6%

Renters

56.4%

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

	Marietta-Alderwood	Whatcom County	Washington
Property value
Median Value	$547,100	$585,800	$564,600
Under $100,000	5.1%	4.7%	4.7%
$100,000 - $200,000	0%	2.9%	3.8%
$200,000 - $300,000	8.9%	5.3%	7%
$300,000 - $500,000	29.6%	25.8%	27.8%
$500,000 - $1,000,000	43.5%	50.8%	40.8%
$1,000,000 and more	12.9%	10.4%	15.9%
Owner-occupied households
With a mortgage	52%	62.7%	66.1%
Without a mortgage	48%	37.3%	33.9%
Median monthly owner costs
With a mortgage	$1,979	$2,307	$2,445
Without a mortgage	$706	$735	$773
Gross rent
Median rent	$1,496	$1,555	$1,760

Education Profile

How educated is the community and how education pays off

Adults with a college degree

33.9%

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

Marietta-Alderwood 33.9%

Whatcom County 39.3%

Washington 39.6%

Adults without a high school diploma

7.7%

of adults (25+) without a high school diploma

Marietta-Alderwood 7.7%

Whatcom County 6.2%

Washington 7.7%

School Enrollment

Who is enrolled in school and at what level

School enrollment

744

population (age 3+) enrolled in school

Nursery / Preschool

K–12

60.6%

College / Undergraduate

30.8%

Graduate / Professional

4.6%

College-going rate (18-24 yr olds)

19%

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

Marietta-Alderwood

19%

Whatcom County

49.6%

Washington

33.2%

Enrollment & school type

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

Population 3+ currently enrolled in a school

	Marietta-Alderwood	Whatcom County	Washington
Total enrolled (age 3+)	744	55,832	1,763,756
Nursery / preschool	4%	5.7%	5.9%
K–12	60.6%	56.6%	69.1%
Kindergarten	10.8%	4.8%	5.1%
Elementary: Grades 1–4	19%	17.3%	20.9%
Elementary: Grades 5–8	13%	16.9%	21.4%
High School: Grades 9–12	17.9%	17.6%	21.6%
College or graduate school	35.3%	37.7%	25.1%
College, undergraduate	30.8%	34.1%	19.6%
Graduate, professional school	4.6%	3.6%	5.5%
College-going rate · 18-24 yr olds	19%	49.6%	33.2%
School type
Public school	81.3%	86.8%	83%
Private school	18.7%	13.2%	17%

Education Attainment by Level & Gender

What is the highest level of education completed among adults

Education attainment

2,686

population 25 years and over

Total adults (25+)

Less than 9th grade

1.4%

9th-12th, no diploma

6.3%

HS graduate

20.9%

Some college no degree

25.4%

Associates degree

12.1%

Bachelors degree

24.8%

Graduate or professional degree

9.1%

Attainment by gender

Male vs Female

Adults (25+) · Share within each education level

% male · % female

Less than 9th grade

86.8% · 13.2%

9th-12th, no diploma

68% · 32%

HS graduate

62.9% · 37.1%

Some college no degree

42.2% · 57.8%

Associates degree

72.5% · 27.5%

Bachelors degree

64.8% · 35.2%

Graduate or professional degree

59% · 41%

Educational Attainment Overview

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

Highest credential completed · adults 25+

	Marietta-Alderwood	Whatcom County	Washington
Population (25+)	2,686	157,791	5,484,391
Less than 9th grade	1.4%	2.4%	3.4%
9th–12th, no diploma	6.3%	3.8%	4.3%
High school diploma or GED	20.9%	20.9%	21.6%
Some college, no degree	25.4%	23%	21%
Associate's degree	12.1%	10.6%	10%
Bachelor's degree or higher	33.9%	39.3%	39.6%
Bachelor's degree	24.8%	24.4%	24%
Graduate or professional	9.1%	14.9%	15.6%
High School or higher	92.3%	93.8%	92.3%

Earnings by education level

percentage as applicable

Median Earnings

$55,681

Median earnings for adults 25+, by level

Less than HS graduate

$60,184

HS graduate

$56,012

Some college or associates

$55,304

Bachelors degree

$52,481

Graduate or professional degree

$—

Poverty Rate

0.8%

for ages 25+, with bachelors degree or higher

Less than HS graduate

2.9%

HS graduate

6.2%

Some college or associates

5.7%

Bachelors degree or higher

0.8%

Outcomes by Education Level

Earnings and poverty rates across education levels (25+)

Adults 25+

	Marietta-Alderwood	Whatcom County	Washington
Median earnings
Population 25+, with earnings	$55,681	$54,738	$62,378
Less than high school graduate	$60,184	$41,479	$37,363
High school graduate (includes equivalency)	$56,012	$45,434	$46,550
Some college or associate's degree	$55,304	$49,090	$53,700
Bachelor's degree	$52,481	$61,536	$81,898
Graduate or professional degree	$—	$84,468	$108,295
Poverty rates
Less than high school graduate	2.9%	19.5%	20.8%
High school graduate (includes equivalency)	6.2%	13.8%	12.2%
Some college or associate's degree	5.7%	10.8%	8.9%
Bachelor's degree or higher	0.8%	5.2%	4.2%

Insights for Marietta-Alderwood, by topic

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