Suffolk County, Massachusetts

County in MA, US

By Neilsberg Research

Last updated May 1, 2026

Key Indicators

A quick look at key numbers

Population

785,121

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

Median Age

33.9

years ∙ half population younger than 33.9, half older

Diversity Index

71.5%

chance two random people differ in race and ethnicity

Nativity

29.8%

foreign-born population

70.2%Native

29.8% Foreign-born

Geographic Context

Location, size, and surroundings

About

Suffolk County is a county in Massachusetts, United States.

Location

County in MA, US

Co-ordinates

DEC42.338551° N, 71.018253° W

DMS42° 20′ 18.78″ N, 71° 01′ 05.71″ W

Population Density & area

13,467/sq mi (5,203/km²)

Total Area

120.3 sq mi (311.4 km²)

Land Area

58.3 sq mi (150.9 km²) · 48.5%

Water Area

62 sq mi (160.5 km²) · 51.5%

Demographics & Living

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

Population Composition

Key characteristics of the population

Sex Distribution

48.2% male

Male 48.2%

Female 51.8%

males per 100 females

Suffolk County 93.2

Massachusetts 95.6

United States 98

Nativity

29.8%

foreign-born population

70.2%Native

29.8% Foreign-born

% Foreign-born

Suffolk County 29.8%

Massachusetts 18%

United States 14.1%

Age Distribution

How the population is spread across age groups

Median Age

33.9

years ∙ half population younger than 33.9, half older

Suffolk County

33.9

Massachusetts

United States

38.9

Dependency ratio

41.4

dependents per 100 working-age adults

Suffolk County 41.4

Massachusetts 59.3

United States 64.4

AGE DISTRIBUTION

Distribution of age group

Median age

	Suffolk County	Massachusetts	United States
Age Group
Children (Under 18)	16%	19.4%	22%
Working age (18-64)	70.7%	62.7%	60.8%
Senior (65+)	13.3%	17.9%	17.2%
Dependency ratio
Total dependency ratio	41.4	59.3	64.4
Child dependency ratio	22.7	30.9	36.1
Old-age dependency ratio	18.8	28.5	28.3

Racial & Ethnic Composition

Racial and ethnic makeup and how it compares

Race & Ethnicity

White

43.6%

Black

17.1%

Asian

9.2%

Hispanic

23.2%

Other

6.9%

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

71.5%

chance two random people differ in race and ethnicity

Suffolk County 71.5%

Massachusetts 52.7%

United States 61.4%

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 Suffolk County population

	Suffolk County	Massachusetts	United States
Hispanic or Latino	23.2%	13.3%	19.3%
Mexican	1.2%	0.8%	11.3%
Puerto Rican	4.1%	4.6%	1.8%
Cuban	0.3%	0.2%	0.8%
Other Hispanic / Latino	17.6%	7.7%	5.5%
Not Hispanic or Latino	76.8%	86.7%	80.7%
One race	71.2%	81.6%	76.4%
White	43.6%	66.6%	57.4%
Black or African American	17.1%	6.4%	11.9%
American Indian and Alaska Native	0.1%	0.1%	0.5%
Asian	9.2%	7.3%	5.9%
Native Hawaiian and Other Pacific Islander	0%	0%	0.2%
Some Other Race	1.1%	1.2%	0.6%
Two or more races (Multiracial)	5.6%	5.1%	4.3%

Household & Families Composition

Household size, type, and family structure

Household structure

47.4% family

Family 47.4%

Non family 52.6%

% family households

Suffolk County 47.4%

Massachusetts 62.4%

United States 64.2%

Average household size

2.25

persons per household

Suffolk County

2.25

Massachusetts

2.44

United States

2.53

Household & Family COMPOSITION

Households

Percentage of Suffolk County population

	Suffolk County	Massachusetts	United States
Total households	327,167	2,785,042	129,227,496
Average houshold size	2.25	2.44	2.53
Family households	155,144	1,737,385	82,990,528
Average family size	3.04	3.04	3.14
Married couple family	94,614	1,277,065	60,637,388
Other families	60,530	460,320	22,353,140
Male householder	14,657	130,288	6,572,819
Female householder	45,873	330,032	15,780,321
Non-family households	172,023	1,047,657	46,236,968
One-person households	119,464	800,741	37,140,836
Male householder	51,935	340,400	16,871,444
Senior (65+) living alone	11,945	114,936	5,225,110
Female householder	67,529	460,341	20,269,392
Senior (65+) living alone	23,173	237,454	10,089,070
Other living arrangements	52,559	246,916	9,096,132

Housing Profile

Housing stock, ownership, rentals, and cost burdens

Total housing units

357,290

housing units

Suffolk County 357,290

Massachusetts 3,030,406

United States 143,775,355

Occupancy status

91.6% occupied

Occupied 91.6%

Vacant 8.4%

vacancy rate

Suffolk County 8.4%

Massachusetts 8.1%

United States 10.1%

Housing Characteristics

How the housing supply is structured and used

Types of Housing unit

19.5%

Single family houses

19.5%

Apartments in multi-unit structures

80.3%

Mobile homes

0.2%

Boat, RV, van, etc

Median Year Built

1949

Half of houses were built before 1949, and half after.

Historic ∙ 1939 or earlier

45.6%

Postwar & mid-century ∙ 1940 - 1969

19%

Late 20th century ∙ 1970 - 1999

17.5%

Modern ∙ 2000 or later

17.8%

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

Housing Characteristics

Units, rooms & bedrooms

Physical characteristics of housing units

	Suffolk County	Massachusetts	United States
Rooms per unit
Median rooms	4.3	5.5	5.5
1–3 rooms	33%	17%	15.1%
4–6 rooms	52.7%	49.5%	51.6%
7+ rooms	14.4%	33.4%	33.4%
Bedrooms
No bedroom / studio	7.5%	3%	2.9%
1 bedroom	23.3%	13.7%	10.9%
2 bedrooms	34.5%	27.7%	25%
3 bedrooms	23.7%	34.3%	38.7%
4+ bedrooms	11%	21.3%	22.4%
At a glance
Median year built	1949	1964	1981
Total housing units	357,290	3,030,406	143,775,355

Occupancy Profile

Who is inside and how they use it

Homeownership

36.5% owners

Renter-occupied 63.5%

Owner-occupied 36.5%

homeownership rate

Suffolk County 36.5%

Massachusetts 62.5%

United States 65.2%

Average household size

2.4

Owner-occupied

2.17

Renter-occupied

owner-occupied average size

Suffolk County 2.4

Massachusetts 2.62

United States 2.64

Housing Characteristics

Occupied unit characteristics

Tenure, crowding, and utilities

	Suffolk County	Massachusetts	United States
Total occupied units	327,167	2,785,042	129,227,496
Year moved in
2020 or later	32.7%	22.5%	24.8%
2010 to 2019	40.4%	38.6%	39.6%
2000 to 2009	12.9%	16.1%	16.4%
1999 or earlier	14.1%	22.9%	19.1%
Occupants per room
1.00 or fewer	95.8%	97.7%	96.6%
1.01 to 1.50	2.2%	1.5%	2.2%
1.51 or more	1.9%	0.8%	1.2%
Vehicles availability
No vehicles	31.6%	11.7%	8.4%
1 vehicle	43.9%	36.1%	33.1%
2 vehicles	18.9%	35.7%	36.6%
3 or more vehicles	5.6%	16.5%	21.9%
House heating fuel used
Gas	59.6%	56.1%	51.4%
Electricity	30.8%	18.6%	41.3%
Solar	0.1%	0.2%	0.3%
Fuel oil, kerosene etc	7.2%	22.4%	3.9%
All other fuels	0.8%	1.9%	2%
No fuel used	1.5%	0.7%	1.2%
Selected characteristics
Lacking complete plumbing	0.4%	0.4%	0.4%
Lacking complete kitchen	1%	0.8%	0.8%
No telephone service available	1%	0.7%	0.9%

Housing Value

What owner-occupied units are worth

Median home value

$705,800

owner-occupied units

Median value(USD)

Suffolk County

$705,800

Massachusetts

$562,100

United States

$332,700

Housing Cost Burden

33%

of homeowners with a mortgage are cost-burdened

% Cost-Burdened Households

Owners with a mortgage

33%

Owners without a mortgage

18.1%

Renters

52%

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

	Suffolk County	Massachusetts	United States
Property value
Median Value	$705,800	$562,100	$332,700
Under $100,000	3.4%	2.9%	11.4%
$100,000 - $200,000	0.8%	3.1%	15.8%
$200,000 - $300,000	2.9%	8.5%	17.8%
$300,000 - $500,000	15.9%	28.7%	26.9%
$500,000 - $1,000,000	55.8%	43.2%	20.9%
$1,000,000 and more	21.3%	13.7%	7.1%
Owner-occupied households
With a mortgage	69.6%	66.4%	60.6%
Without a mortgage	30.4%	33.6%	39.4%
Median monthly owner costs
With a mortgage	$2,962	$2,726	$1,963
Without a mortgage	$1,046	$1,043	$638
Gross rent
Median rent	$2,129	$1,762	$1,413

Education Profile

How educated is the community and how education pays off

Adults with a college degree

50.6%

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

Suffolk County 50.6%

Massachusetts 47.3%

United States 35.7%

Adults without a high school diploma

12.5%

of adults (25+) without a high school diploma

Suffolk County 12.5%

Massachusetts 8.6%

United States 10.4%

School Enrollment

Who is enrolled in school and at what level

School enrollment

205,175

population (age 3+) enrolled in school

Nursery / Preschool

4.2%

K–12

44.4%

College / Undergraduate

36.1%

Graduate / Professional

15.4%

College-going rate (18-24 yr olds)

63.6%

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

Suffolk County

63.6%

Massachusetts

50.5%

United States

40.9%

Enrollment & school type

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

Population 3+ currently enrolled in a school

	Suffolk County	Massachusetts	United States
Total enrolled (age 3+)	205,175	1,677,525	80,089,790
Nursery / preschool	4.2%	6%	5.7%
K–12	44.4%	60.9%	67.6%
Kindergarten	4%	4.4%	5%
Elementary: Grades 1–4	12.6%	17.3%	19.8%
Elementary: Grades 5–8	13.4%	18.7%	21%
High School: Grades 9–12	14.4%	20.4%	21.7%
College or graduate school	51.5%	33.2%	26.7%
College, undergraduate	36.1%	24.3%	21%
Graduate, professional school	15.4%	8.9%	5.8%
College-going rate · 18-24 yr olds	63.6%	50.5%	40.9%
School type
Public school	53%	71.9%	82%
Private school	47%	28.1%	18%

Education Attainment by Level & Gender

What is the highest level of education completed among adults

Education attainment

552,101

population 25 years and over

Total adults (25+)

Less than 9th grade

7.6%

9th-12th, no diploma

4.9%

HS graduate

20.2%

Some college no degree

11.6%

Associates degree

5.1%

Bachelors degree

27.1%

Graduate or professional degree

23.5%

Attainment by gender

Male vs Female

Adults (25+) · Share within each education level

% male · % female

Less than 9th grade

47.3% · 52.7%

9th-12th, no diploma

48.5% · 51.5%

HS graduate

52.5% · 47.5%

Some college no degree

48.1% · 51.9%

Associates degree

41.8% · 58.2%

Bachelors degree

48.7% · 51.3%

Graduate or professional degree

45.3% · 54.7%

Educational Attainment Overview

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

Highest credential completed · adults 25+

	Suffolk County	Massachusetts	United States
Population (25+)	552,101	4,987,302	230,807,303
Less than 9th grade	7.6%	4.3%	4.7%
9th–12th, no diploma	4.9%	4.3%	5.7%
High school diploma or GED	20.2%	22.6%	26%
Some college, no degree	11.6%	14.1%	19.1%
Associate's degree	5.1%	7.5%	8.8%
Bachelor's degree or higher	50.6%	47.3%	35.7%
Bachelor's degree	27.1%	25.5%	21.6%
Graduate or professional	23.5%	21.8%	14.1%
High School or higher	87.5%	91.4%	89.6%

Earnings by education level

percentage as applicable

Median Earnings

$66,348

Median earnings for adults 25+, by level

Less than HS graduate

$31,555

HS graduate

$40,602

Some college or associates

$48,245

Bachelors degree

$84,143

Graduate or professional degree

$99,751

Poverty Rate

6.7%

for ages 25+, with bachelors degree or higher

Less than HS graduate

30.4%

HS graduate

18.2%

Some college or associates

15%

Bachelors degree or higher

6.7%

Outcomes by Education Level

Earnings and poverty rates across education levels (25+)

Adults 25+

	Suffolk County	Massachusetts	United States
Median earnings
Population 25+, with earnings	$66,348	$66,782	$52,696
Less than high school graduate	$31,555	$36,200	$32,485
High school graduate (includes equivalency)	$40,602	$46,175	$40,153
Some college or associate's degree	$48,245	$52,923	$47,260
Bachelor's degree	$84,143	$81,726	$70,044
Graduate or professional degree	$99,751	$102,561	$90,720
Poverty rates
Less than high school graduate	30.4%	25.1%	24.2%
High school graduate (includes equivalency)	18.2%	12.9%	14.4%
Some college or associate's degree	15%	9.3%	9.8%
Bachelor's degree or higher	6.7%	4.1%	4.5%

Insights for Suffolk County, 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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