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South Dakota ZIP Codes
Brown County
Groton, SD
57445
57445 ZIP Code — Groton, SD
Brown County, South Dakota
ZIP code 57445 is located in
Groton ,
South Dakota ,
within Brown County .
It covers approximately 253.91 square miles and serves a population of
1,910 residents.
This is a standard ZIP code in the Central (CT) timezone,
served by area code 605 .
About ZIP code 57445
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 $173,700. Owner-occupancy is high at 79%, well above the national average.
Median household income is $81,964. The poverty rate of 4% is below the national average.
The dominant occupation class is management, business, and professional, with education and healthcare as the leading industry. The average commute of 17 minutes is near the national average.
Educational attainment is near the national average, with 21% of residents holding a bachelor's degree or higher.
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Cities in ZIP code 57445
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Nearby ZIP codes
Demographics
updated 05/2026
Population
Total population
1,910
Population density
8 / sq mi
State FIPS
46
County FIPS
013
Geography
Land area
253.91 sq mi
Water area
0.09 sq mi
Latitude
45.4618
Longitude
-98.1445
Timezone
Central (CT)
Area code
605
Economics
updated 05/2026
Household income
Income range
This ZIP
County avg
State avg
Under $50k
33.7%
39.9%
41.7%
$50k – $100k
34.8%
34.8%
33.8%
$100k – $200k
28.0%
20.4%
20.1%
Over $200k
3.4%
4.9%
4.4%
Demographics & statistics
$81,964
Median household income
$173,700
Median home value
21.1%
Bachelor's or higher
Age distribution
Age summary
Group Count %
Under 18 491 25.7%
18 and over 1,419 74.3%
65 and over 375 19.6%
Median age 37.1 years
Race & ethnicity
Group Count %
White 1,849 94.9%
Two or more races 40 2.1%
Hispanic or Latino 38 2%
Other race 21 1.1%
Household income
Income range
This ZIP
County avg
State avg
Under $50k
33.7%
39.9%
41.7%
$50k – $100k
34.8%
34.8%
33.8%
$100k – $200k
28.0%
20.4%
20.1%
Over $200k
3.4%
4.9%
4.4%
Range % of households
Under $10k 2.7%
$10k–$15k 0.9%
$15k–$25k 7.4%
$25k–$35k 10.5%
$35k–$50k 9.8%
$50k–$75k 15.1%
$75k–$100k 16.4%
$100k–$150k 16.4%
$150k–$200k 13.3%
$200k+ 7.5%
Median income $81,964
Housing
Housing overview
Metric Value
Median home value $173,700
Median rent / month $920
Owner occupied 78.9%
Renter occupied 21.1%
Vacant 13.9%
Single-family detached 71.0%
Large apartment buildings 0.7%
Mobile homes 10.6%
Median rooms 6.4
Avg household size (owned) 2.61
Year built
Era %
2020 or later 0.0%
2010–2019 11.8%
2000–2009 15.0%
1990–1999 13.6%
1980–1989 4.9%
1970–1979 12.2%
1960–1969 7.2%
1950–1959 8.3%
1940–1949 3.2%
1939 or earlier 23.7%
Bedrooms
Size % of units
No bedroom (studio) 0.0%
1 bedroom 2.2%
2 bedrooms 28.8%
3 bedrooms 34.6%
4 bedrooms 24.1%
5+ bedrooms 10.2%
Vehicles per household
Vehicles % of households
No vehicle 3.5%
1 vehicle 26.4%
2 vehicles 24.7%
3 or more 45.5%
Heating fuel
Fuel type %
Utility gas 49.9%
Electricity 35.7%
Propane / LP gas 12.8%
Fuel oil 0.9%
Households & families
Household type Count %
Married-couple family 391 50.5%
Cohabiting couple 53 6.8%
Male householder, no spouse 173 22.4%
Female householder, no spouse 157 20.3%
Households with children under 18 247 31.9%
Households with seniors (65+) 226 29.2%
Average household size 2.41
Marital status
Status Male Female
Never married 26.5% 24.7%
Married 55.6% 53.7%
Separated 0.0% 0.3%
Widowed 3.4% 13.1%
Divorced 14.5% 8.3%
Education
Some college, no degree
24.2%
Graduate / professional
7.2%
Metric %
HS diploma or higher 96.1%
Bachelor's or higher 21.1%
School enrollment (ages 3–17)
Type Count %
Nursery / preschool 8 1.7%
Kindergarten 18 3.8%
Elementary school 256 54.7%
High school 128 27.4%
College / grad school 58 12.4%
Employment
Industry of employment
Education & healthcare
30.1%
Agriculture & mining
9.0%
Finance & real estate
7.3%
Arts, food & hospitality
3.6%
Transportation & utilities
2.8%
Professional & management
2.6%
Public administration
2.5%
Occupation
Category %
Management, business & arts 36.9%
Service 16.1%
Sales & office 16.1%
Natural resources & construction 12.8%
Production & transportation 18.1%
Employment type
Type %
Private sector 75.7%
Government 12.0%
Self-employed 11.8%
Unpaid family workers 0.5%
Commute
Method %
Drive alone 90.2%
Carpool 4.0%
Public transit 0.0%
Walk 3.0%
Work from home 2.8%
Other means 0.0%
Avg commute (minutes) 16.7
Poverty
Married-couple families
0.0%
Female-led households
35.9%
Income support
Source % of households
Social Security 28.8%
Retirement income 19.1%
Supplemental Security 1.6%
Cash public assistance 1.6%
Food stamps / SNAP 2.5%
Health indicators
Condition %
Obesity 32.2%
High blood pressure 34.0%
High cholesterol 33.4%
Diabetes 9.3%
Heart disease 7.0%
Stroke 3.1%
Asthma 8.0%
Arthritis 26.8%
Kidney disease 3.0%
Pulmonary disease 5.6%
Cancer 8.1%
Behavior / access %
Smoking 16.8%
Binge drinking 19.3%
No physical activity 23.3%
Less than 7 hrs sleep 28.6%
Depression 15.4%
Fair or poor health 10.4%
Poor mental health 9.9%
Poor physical health 8.4%
No health insurance 11.0%
Visited doctor (checkup) 76.1%
Visited dentist 70.3%
Cholesterol screening 90.3%
Teeth loss 12.6%
Veterans & disability
Veterans Count %
Civilian veterans 81 5.7%
Disability %
Any disability 10.0%
Under 18 1.2%
18–64 years 6.9%
65 and over 33.0%
Health insurance coverage
Type %
Private insurance 87.0%
Public insurance 23.3%
No insurance 5.5%
Uninsured under 19 4.5%
Language & origin
Language spoken at home (age 5+)
Language Count %
English only 1,825 95.5%
Spanish 24 1.3%
Other Indo-European 24 1.3%
Asian & Pacific Islander 0 0.0%
Other languages 0 0.0%
Place of birth & citizenship
Origin Count %
Native born (US) 1,890 99.0%
Born in same state 1,883 98.6%
Born in different state 1,555 81.4%
Foreign born 7 0.4%
Naturalized citizen 20 1.0%
Not a US citizen 0 0.0%
Ancestry
Ancestry Count %
Polish 448 23.5%
Italian 172 9%
French 168 8.8%
Arab 69 3.6%
Ancestry Count %
German 24 1.3%
English 8 0.4%
Dutch 2 0.1%
Technology access
Metric % of households
Computer access 40.5%
Internet access 89.0%
Source: U.S. Census Bureau, American Community Survey 2025 estimates.
Frequently asked questions about ZIP code 57445
What city is ZIP code 57445 in?
ZIP code 57445 is primarily assigned to Groton, South Dakota.
What county is ZIP code 57445 in?
ZIP code 57445 falls within Brown County, South Dakota.
What is the typical home value in ZIP code 57445?
The median home value in ZIP code 57445 is $173,700.
What is the population of ZIP code 57445?
ZIP code 57445 has an estimated population of 1,910 residents, with a density of 8 people per square mile.
What is the median household income in ZIP code 57445?
The median household income in ZIP code 57445 is $81,964, above the national median of ~$75,000.
What timezone is ZIP code 57445 in?
ZIP code 57445 observes the CST timezone.
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