57551 ZIP Code — Martin, SD

Bennett County, South Dakota

ZIP code 57551 is located in Martin, South Dakota, within Bennett County. It covers approximately 753.14 square miles and serves a population of 2,085 residents. This is a standard ZIP code in the Mountain (MT) timezone, served by area code 605.

About ZIP code 57551

The housing stock consists of predominantly single-family detached homes. Most homes were built in the pre-1940, giving the area an established character. Median home value is $118,800. Owner-occupancy sits near the national average at 69%.

The gap between median ($53,438) and mean household income suggests income inequality — a small number of higher earners pull the average up. Poverty affects 18% of residents, above the national average.

The dominant occupation class is management, business, and professional, with education and healthcare as the leading industry. The average commute of 11 minutes is near the national average.

Educational attainment is near the national average, with 26% of residents holding a bachelor's degree or higher.

Health indicators show elevated rates of smoking (29%) compared to national benchmarks. 24% of residents lack health insurance, above the national average.

2,085

population

753.14

sq mi land

Standard

ZIP type

Mountain (MT)

timezone

57551 ZIP code map

Cities in ZIP code 57551

Below are the cities the US Postal Service accepts for ZIP code 57551. Using any city not on this list may result in mail delivery delays.

City	Status
Martin	Acceptable
Martin	Preferred

Nearby ZIP codes

57714 Allen (13.7 mi)

Demographics updated 06/2026

Population
Total population	2,085
Population density	3 / sq mi
State FIPS	46
County FIPS	007

Geography
Land area	753.14 sq mi
Water area	4.57 sq mi
Latitude	43.1929
Longitude	-101.6687
Timezone	Mountain (MT)
Area code	605

Total population by age

Gender

Race & ethnicity

Economics updated 06/2026

Household income

Income range	This ZIP	County avg	State avg
Under $50k	55.2%	58.1%	41.7%
$50k – $100k	32.1%	30.2%	33.8%
$100k – $200k	8.7%	8.4%	20.1%
Over $200k	3.9%	3.3%	4.4%

Demographics & statistics

2,085

Population

People per sq mi

34.9

Median age

$53,438

Median household income

$31,805

Per capita income

$118,800

Median home value

$759

Median monthly rent

68.8%

Home ownership

18.0%

Poverty rate

3.6%

Unemployment

696

Housing units

25.6%

Bachelor's or higher

Age distribution

Male Female

Under 5

5–9

10–14

112

15–19

118

20–24

121

25–34

128

116

35–44

122

117

45–54

123

55–59

60–64

65–74

75–84

85+

← Male

Female →

Age summary

Group	Count	%
Under 18	667	32.0%
18 and over	1,418	68.0%
65 and over	300	14.4%
Median age	34.9 years

Race & ethnicity

White 61.4%

American Indian / Alaska Native 31.6%

Two or more races 4.1%

Asian 2.2%

Black or African American 0.3%

Hispanic or Latino 0.2%

Other race 0.2%

Group	Count	%
White	1,283	61.4%
American Indian / Alaska Native	661	31.6%
Two or more races	85	4.1%
Asian	45	2.2%
Black or African American	6	0.3%
Hispanic or Latino	5	0.2%
Other race	5	0.2%

Household income

Income range	This ZIP	County avg	State avg
Under $50k	55.2%	58.1%	41.7%
$50k – $100k	32.1%	30.2%	33.8%
$100k – $200k	8.7%	8.4%	20.1%
Over $200k	3.9%	3.3%	4.4%

Under $10k 6.6%

$10k–$15k 4.4%

$15k–$25k 11.8%

$25k–$35k 9.0%

$35k–$50k 17.6%

$50k–$75k 16.6%

$75k–$100k 9.0%

$100k–$150k 11.2%

$150k–$200k 5.2%

$200k+ 8.7%

Range	% of households
Under $10k	6.6%
$10k–$15k	4.4%
$15k–$25k	11.8%
$25k–$35k	9.0%
$35k–$50k	17.6%
$50k–$75k	16.6%
$75k–$100k	9.0%
$100k–$150k	11.2%
$150k–$200k	5.2%
$200k+	8.7%
Median income	$53,438

Housing

Home values

Under $50k 16.5%

$50k–$100k 30.3%

$100k–$150k 11.1%

$150k–$200k 16.1%

$200k–$300k 9.4%

$300k–$500k 6.0%

$500k–$1M 6.3%

$1M+ 4.2%

Housing overview

Metric	Value
Median home value	$118,800
Median rent / month	$759
Owner occupied	68.8%
Renter occupied	31.2%
Vacant	18.8%
Single-family detached	82.4%
Large apartment buildings	0.3%
Mobile homes	8.6%
Median rooms	5.5
Avg household size (owned)	2.64

Year built

Era	%
2020 or later	0.0%
2010–2019	1.4%
2000–2009	3.2%
1990–1999	9.0%
1980–1989	11.7%
1970–1979	16.5%
1960–1969	10.3%
1950–1959	13.7%
1940–1949	13.9%
1939 or earlier	20.2%

Bedrooms

Size	% of units
No bedroom (studio)	1.5%
1 bedroom	4.9%
2 bedrooms	33.2%
3 bedrooms	30.3%
4 bedrooms	27.0%
5+ bedrooms	3.1%

Vehicles per household

Vehicles	% of households
No vehicle	6.3%
1 vehicle	28.7%
2 vehicles	37.6%
3 or more	27.3%

Heating fuel

Fuel type	%
Utility gas	2.1%
Electricity	40.2%
Propane / LP gas	47.4%
Fuel oil	0.5%
Wood	8.7%

Households & families

Household type	Count	%
Married-couple family	353	46.6%
Cohabiting couple	51	6.7%
Male householder, no spouse	146	19.3%
Female householder, no spouse	207	27.3%
Households with children under 18	286	37.8%
Households with seniors (65+)	203	26.8%
Average household size	2.70

Marital status

Status	Male	Female
Never married	33.8%	34.0%
Married	53.6%	43.5%
Separated	2.0%	0.9%
Widowed	3.3%	6.3%
Divorced	7.2%	15.4%

Education

Less than 9th grade 1.8%

Some HS, no diploma 1.0%

HS graduate 37.1%

Some college, no degree 22.7%

Associate's degree 11.8%

Bachelor's degree 20.9%

Graduate / professional 4.7%

Metric	%
HS diploma or higher	97.2%
Bachelor's or higher	25.6%

School enrollment (ages 3–17)

Type	Count	%
Nursery / preschool	24	3.6%
Kindergarten	31	4.7%
Elementary school	302	45.7%
High school	210	31.8%
College / grad school	94	14.2%

Employment

Industry of employment

Education & healthcare 30.5%

Agriculture & mining 17.9%

Retail trade 10.3%

Arts, food & hospitality 8.7%

Construction 7.0%

Public administration 6.9%

Other services 3.8%

Transportation & utilities 3.5%

Manufacturing 3.3%

Professional & management 3.0%

Information 2.8%

Finance & real estate 1.2%

Wholesale trade 1.0%

Occupation

Category	%
Management, business & arts	44.6%
Service	10.8%
Sales & office	16.3%
Natural resources & construction	13.4%
Production & transportation	14.9%

Employment type

Type	%
Private sector	57.3%
Government	26.2%
Self-employed	16.5%
Unpaid family workers	0.0%

Commute

Method	%
Drive alone	77.4%
Carpool	5.4%
Public transit	0.0%
Walk	11.3%
Work from home	5.2%
Other means	0.7%
Avg commute (minutes)	11.4

Poverty

All people 18.0%

Under 18 years 27.4%

18 and over 13.5%

Married-couple families 6.8%

Female-led households 25.2%

Income support

Source	% of households
Social Security	26.6%
Retirement income	18.1%
Supplemental Security	2.2%
Cash public assistance	2.8%
Food stamps / SNAP	8.7%

Health indicators

Condition	%
Obesity	37.8%
High blood pressure	36.9%
High cholesterol	30.6%
Diabetes	14.2%
Heart disease	9.6%
Stroke	5.2%
Asthma	11.7%
Arthritis	26.7%
Kidney disease	4.3%
Pulmonary disease	9.9%
Cancer	6.9%

Behavior / access	%
Smoking	29.4%
Binge drinking	17.8%
No physical activity	30.2%
Less than 7 hrs sleep	29.5%
Depression	16.3%
Fair or poor health	20.4%
Poor mental health	14.1%
Poor physical health	13.7%
No health insurance	16.0%
Visited doctor (checkup)	74.6%
Visited dentist	54.8%
Cholesterol screening	85.1%
Teeth loss	26.3%

Veterans & disability

Veterans	Count	%
Civilian veterans	123	8.7%

Disability	%
Any disability	11.8%
Under 18	2.4%
18–64 years	10.6%
65 and over	39.6%

Health insurance coverage

Type	%
Private insurance	42.6%
Public insurance	38.9%
No insurance	23.8%
Uninsured under 19	32.3%

Language & origin

Language spoken at home (age 5+)

Language	Count	%
English only	1,937	92.9%
Spanish	30	1.5%
Other Indo-European	0	0.0%
Asian & Pacific Islander	0	0.0%
Other languages	25	1.3%

Place of birth & citizenship

Origin	Count	%
Native born (US)	2,041	97.9%
Born in same state	2,029	97.3%
Born in different state	1,293	62.0%
Foreign born	12	0.6%
Naturalized citizen	44	2.1%
Not a US citizen	12	27.3%

Ancestry

Ancestry	Count	%
Polish	129	6.2%
Italian	102	4.9%
French	96	4.6%

Ancestry	Count	%
Dutch	69	3.3%
Arab	35	1.7%
English	14	0.7%

Technology access

Metric	% of households
Computer access	36.3%
Internet access	86.0%

Source: U.S. Census Bureau, American Community Survey 2025 estimates.

Frequently asked questions about ZIP code 57551

What city is ZIP code 57551 in?

ZIP code 57551 is primarily assigned to Martin, South Dakota.

What county is ZIP code 57551 in?

ZIP code 57551 falls within Bennett County, South Dakota.

Is ZIP code 57551 family-oriented?

32% of residents in ZIP code 57551 are under 18, reflecting a younger, family-oriented community.

What is the poverty rate in ZIP code 57551?

18% of residents in ZIP code 57551 live below the poverty line, above the national average.

What is the typical home value in ZIP code 57551?

The median home value in ZIP code 57551 is $118,800.

What is the population of ZIP code 57551?

ZIP code 57551 has an estimated population of 2,085 residents, with a density of 3 people per square mile.

What timezone is ZIP code 57551 in?

ZIP code 57551 observes the MST timezone.