County · South Dakota
Lyman County, South Dakota
Lyman County, South Dakota. Lyman County had 3,694 residents in 2025 by the Census Bureau's estimate, down 0.5% since 2020, while South Dakota grew 5.5%. It holds 13 places (4 cities, villages and boroughs, 6 towns and townships and 3 census-designated) and 2 census tracts. GEOID 46085.
Residents, July 2025 estimate
3,694
Census Bureau estimate (no margin published)
2020 Census count: 3,718 · ACS 2020-2024: 3,724
Median household income
$67,143
±$7,804 (90% margin)
South Dakota: $75,081
Median home value
$165,800
±$10,861 (90% margin)
South Dakota: $257,400
Median gross rent
$651
±$54 (90% margin)
South Dakota: $946
How many people live in Lyman County, and is it growing?
The 2020 Census counted 3,718 residents in Lyman County. The Census Bureau estimates 3,694 for July 1, 2025, down 0.5% since 2020, while South Dakota grew 5.5%. The 2020-2024 American Community Survey puts the population at 3,724 over 1,642 square miles of land.
| Measure | Lyman County | South Dakota | Change since 2015-2019 |
|---|---|---|---|
| Total population | 3,724 | 907,428 | −124 |
| Households | 1,188±83 | 365,544 | −209 |
| Average household size | 3.07±0.19 | 2.39 | +0.37 |
| Housing units | 1,553±37 | 408,584 | −179 |
Lyman County's population since 2000
From 3,895 in 2000 to 3,694 in 2025: down 5.2%. The 2000, 2010 and 2020 figures are census counts. The 2005 figure is the Census Bureau's intercensal estimate, revised to fit the 2000 and 2010 counts and drawn on 2010 boundaries; 2015 and 2025 are July 1 estimates made from the census before them.
Source: The 2000, 2010 and 2020 Census counts and the Census Bureau's population estimates (intercensal 2000-2010, Vintage 2020, Vintage 2025) · Census population estimates
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026); PEP Vintage 2025 (CO-EST2025); 2020 Census · Check it at data.census.gov
What cities and towns are in Lyman County?
Lyman County holds 13 places: 4 cities, villages and boroughs (incorporated places), 6 towns and townships (county subdivisions with their own government) and 3 census-designated places. The largest is Lower Brule with 743 residents (2020-2024). Places that cross a county line are listed with the share of their 2020 residents who live in this county.
| Lower Brule | 703 | $28,750 |
|---|---|---|
| West Brule | 538 | $37,917 |
| PreshoGEOID 4651820 | 472 | $63,393 |
| Oacoma | 386 | $73,333 |
| KennebecGEOID 4633580 | 281 | $74,896 |
| RelianceGEOID 4654020 | 128 | $55,313 |
| Vivian TownshipGEOID 4608567660 | 113 | $101,250 |
| VivianGEOID 4667620 | 98 | $61,528 |
| Iona TownshipGEOID 4608531740 | 75 | not published |
| Oacoma TownshipGEOID 4608546220 | 70 | $163,929 |
| Rex TownshipGEOID 4608554260 | 36 | not published |
| Pratt TownshipGEOID 4608551780 | 29 | not published |
| Bailey TownshipGEOID 4608503220 | 15 | not published |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026); 2020 place-by-county parts · Check it at data.census.gov
Who lives in Lyman County?
The median resident of Lyman County is 36.1 years old; 28.0% are under 18 and 18.3% are 65 or older. The largest group is non-Hispanic white residents at 57.1%, then non-Hispanic American Indian and Alaska Native residents at 39.3%.
| Measure | Lyman County | South Dakota | Change since 2015-2019 |
|---|---|---|---|
| Median age | 36.1±1.3 | 38.0 | no clear change |
| Under 18 years | 28.0%±0.4 pts | 24.2% | – |
| 65 years and over | 18.3%±0.1 pts | 18.0% | – |
| Hispanic or Latino (any race) | 1.2% | 4.8% | – |
| White alone, not Hispanic | 57.1%±0.7 pts | 79.8% | +1.5 pts |
| Black or African American alone, not Hispanic | 0.0%±1.6 pts | 2.1% | – |
| Asian alone, not Hispanic | 0.0%±0.1 pts | 1.4% | – |
| American Indian and Alaska Native alone, not Hispanic | 39.3%±1.6 pts | 7.1% | – |
| Native Hawaiian and Other Pacific Islander alone, not Hispanic | 0.3%±0.4 pts | 0.0% | – |
| Two or more races, not Hispanic | 2.0%±0.9 pts | 4.4% | – |
| Some other race alone, not Hispanic | 0.0%±0.1 pts | 0.3% | – |
| Born outside the United States | 0.6%±0.4 pts | 4.0% | – |
| Speak a language other than English at home (age 5+) | 3.7%±1.6 pts | 7.1% | – |
| Civilian veterans (age 18+) | 5.1%±1.3 pts | 7.9% | – |
| With a disability | 13.0%±2.3 pts | 12.5% | – |
| No health insurance coverage | 21.3%±3.2 pts | 9.0% | +5.3 pts |
| High school graduate or higher (age 25+) | 89.4%±2.4 pts | 93.2% | – |
| Bachelor's degree or higher (age 25+) | 24.5%±4.4 pts | 31.9% | no clear change |
| Graduate or professional degree (age 25+) | 4.9%±1.6 pts | 10.0% | – |
| Moved from another state in the past year | 1.4%±2.2 pts | 3.2% | – |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) (Data Profiles DP02, DP05) · Check it at data.census.gov
What do households in Lyman County earn?
Half of Lyman County's 1,188 households earn less than $67,143 a year (±$7,804), against $75,081 in South Dakota. In 2015-2019 it was $66,288 in 2024 dollars; the margins of error cannot tell the two periods apart. 23.7% of residents live below the poverty line.
| Measure | Lyman County | South Dakota | Change since 2015-2019 |
|---|---|---|---|
| Median household income | $67,143±$7,804 | $75,081 | no clear change |
| Mean household income | $99,810±$14,837 | $98,527 | – |
| Per capita income | $37,079±$4,787 | $40,550 | +$8,958 |
| People below the poverty line | 23.7%±4.1 pts | 11.9% | no clear change |
| Children under 18 below the poverty line | 30.1%±7.4 pts | 14.3% | no clear change |
| Households receiving SNAP | 11.4%±2.9 pts | 7.9% | – |
| Households with a broadband subscription | 82.4%±4.2 pts | 89.6% | – |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) (Data Profile DP03) · Check it at data.census.gov
What does housing cost in Lyman County?
Owners occupy 69.9% of Lyman County's occupied homes and renters 30.1%. The median owner-occupied home is valued at $165,800 by its owner (±$10,861). The median renter pays $651 a month including utilities, and 21.4% of renters pay 35% or more of their income on rent.
| Measure | Lyman County | South Dakota | Change since 2015-2019 |
|---|---|---|---|
| Median home value (owner-occupied) | $165,800±$10,861 | $257,400 | +$39,285 |
| Median gross rent | $651±$54 | $946 | no clear change |
| Renters paying 35% or more of income on rent | 21.4%±10.6 pts | 30.4% | no clear change |
| Median monthly owner costs, with a mortgage | $1,396±$132 | $1,680 | – |
| Owner-occupied homes | 69.9%±5.1 pts | 68.6% | no clear change |
| Housing units | 1,553±37 | 408,584 | −179 |
| Homeowner vacancy rate | 0.2%±0.4 pts | 0.8% | – |
| Rental vacancy rate | 10.1%±4.3 pts | 6.0% | – |
| Single-family detached homes | 80.9%±3.5 pts | 66.9% | – |
| Mobile homes | 10.8%±2.8 pts | 7.2% | – |
| Built 2020 or later | 0.6%±0.6 pts | 2.3% | – |
| Built 1939 or earlier | 13.1%±3.4 pts | 15.8% | – |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) (Data Profile DP04) · Check it at data.census.gov
How many new homes is Lyman County building?
Builders took permits for 7 new housing units across Lyman County in 2025 (7 single-family), 1.9 per 1,000 residents.
Source: Building Permits Survey, annual county files 2019-2025, U.S. Census Bureau · Census Building Permits Survey
How do people in Lyman County get to work?
73.4% of Lyman County's workers drive alone and 11.2% work from home. The average trip to work takes 15.8 minutes. The unemployment rate in 2020-2024 averaged 4.0%.
| Measure | Lyman County | South Dakota | Change since 2015-2019 |
|---|---|---|---|
| In the labor force (age 16+) | 57.3%±4.7 pts | 67.2% | – |
| Unemployment rate | 4.0%±1.8 pts | 2.9% | −3.0 pts |
| Drove alone to work | 73.4%±5.9 pts | 77.0% | – |
| Carpooled | 8.2%±3.3 pts | 8.3% | – |
| Public transportation | 0.8%±1.1 pts | 0.5% | – |
| Walked | 3.1%±2.3 pts | 3.1% | – |
| Worked from home | 11.2%±4.1 pts | 9.7% | no clear change |
| Mean travel time to work | 15.8 min±2.1 | 17.8 min | +2.8 min |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) (Data Profile DP03) · Check it at data.census.gov
What are Lyman County's census tracts?
Lyman County is divided into 2 census tracts. Among those with a reliable estimate, median household income runs from $37,614 (Tract 9401) to $77,375 (Tract 9726).
| Tract 940146085940100 | 1,517±105 | $37,614 |
|---|---|---|
| Tract 972646085972600 | 2,207±105 | $77,375 |
Source: American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) · Check it at data.census.gov
How does Lyman County compare with South Dakota's other counties?
| Measure | Rank |
|---|---|
| Population | 43rd of 66 |
| Growth 2020-2025 | 46th of 66 |
| Residents per square mile | 51st of 66 |
| Median household income | 43rd of 66 |
| Median home value | 35th of 66 |
| Median gross rent | 50th of 65 |
| Poverty rate | 12th of 65 |
| Bachelor's degree or higher | 37th of 66 |
| Median age | 52nd of 66 |
Source: PlainCities ranks from the American Community Survey 2020-2024 5-year estimates, U.S. Census Bureau (released January 2026) and PEP Vintage 2025 · How ranks are computed
How these figures are made: methodology and release checks · reading a margin of error · every state · corrections
Not on this page: crime, weather and schools for Lyman County are other agencies' records. Crime: the FBI's Crime Data Explorer · climate: NOAA's U.S. Climate Normals · schools: the National Center for Education Statistics' school search.