Counties in South Dakota by median age on 1 July (US county estimates)

Custer County had the highest median age on 1 July (US county estimates) of 66 counties in 2017, at 55.1 years. Todd County had the lowest, at 24.2 years. The median was 41.8 years. Source: the U.S. Census Bureau.

Highest55.1Custer County

Lowest24.2Todd County

Median41.866 counties

Top 40 counties, 2017

years. Source: U.S. Census Bureau, Population Estimates Program, county population by age and sex: median age (MEDIAN_AGE_TOT) on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage. Retrieved 2026-10-12.

Full ranking

Rank	Counties	2017 years	Change on 2016
1	Custer County	55.1	+0.8
2	Fall River County	53.9	+1.1
3	Campbell County	52.9	+0.5
4	Potter County	52.4	+0.7
5	McPherson County	49.1	-1.1
6	Douglas County	48.3	-0.8
6	Jerauld County	48.3	-1.8
8	Hand County	48.1	-0.3
9	Gregory County	47.7	-0.4
10	Perkins County	47.4	+0.4
11	Day County	47.2	+0.1
11	Faulk County	47.2	-0.1
13	Hyde County	46.8	-1.6
14	Miner County	46.4	+0.3
15	Kingsbury County	46.1	-0.4
16	Jones County	45.6	-1.1
17	Sully County	45.3	+0.7
18	Grant County	44.7	-0.1
18	Haakon County	44.7	-1.6
20	Edmunds County	44.3	-0.1
21	Deuel County	43.9	-0.7
21	Tripp County	43.9	-0.3
23	Hutchinson County	43.5	-0.3
24	Walworth County	43.2	-0.6
25	Bon Homme County	43.1	-0.2
26	Marshall County	42.6	-0.8
27	Aurora County	42.5	-0.3
28	Butte County	42.3	+0.1
28	Harding County	42.3	+0.6
28	Turner County	42.3	-0.5
31	Lawrence County	42.2	+0.2
32	Spink County	42	-0.7
33	Lake County	41.9	+0.4
34	Brule County	41.7	-0.6
34	Yankton County	41.7	-0.1
36	Stanley County	41.5	+0.2
37	McCook County	41.4	-0.4
38	Moody County	41.1	-0.2
38	Union County	41.1	+0.1
40	Clark County	40.7	-1.1
41	Davison County	39.3	+0.4
42	Hughes County	39.2	-0.3
43	Roberts County	39.1	-0.3
44	Sanborn County	38.9	-1.2
45	Codington County	38.2	0
46	Pennington County	37.6	+0.2
47	Hanson County	37.3	0
48	Brown County	37.1	-0.2
49	Beadle County	37	-0.6
50	Charles Mix County	36.8	+0.2
51	Hamlin County	35.9	-0.5
52	Meade County	35.7	+0.2
53	Minnehaha County	35	+0.1
54	Lyman County	34.7	+0.1
55	Lincoln County	34.6	+0.1
56	Mellette County	33.4	-0.5
57	Jackson County	32.8	+0.5
58	Dewey County	30.9	+0.3
59	Bennett County	30.5	+0.5
59	Ziebach County	30.5	+1
61	Corson County	28.7	-1
62	Brookings County	28.6	+0.4
63	Buffalo County	26	+0.2
64	Clay County	25.2	+0.2
65	Oglala Lakota County	24.9	+0.2
66	Todd County	24.2	-0.3

Other periods

About this ranking

Age that divides the resident population of a US county into two halves of equal size on 1 July, from Census Bureau population estimates calculated by single year of age.

Counties only: the county file has no state or national medians, and medians cannot be added up. A single-year estimate, unlike median_age, which for US places is a five-year American Community Survey estimate.

Every value in the ranking comes from the same publisher and the same period, so the counties are compared on one definition. Equal values share a rank.

How to cite

U.S. Census Bureau. Population Estimates Program, county population by age and sex: median age (MEDIAN_AGE_TOT) on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage. https://www.census.gov/programs-surveys/popest/data/data-sets.html. Retrieved 2026-10-12.

Citation styles

The publisher is the author. Invokely is named only as the place the figures were read, where a style asks for it.

APA 7

U.S. Census Bureau. (2026). Population Estimates Program, county population by age and sex: median age (MEDIAN_AGE_TOT) on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage (Counties in South Dakota by median age on 1 July (US county estimates), 2017) [Data set]. Retrieved October 12, 2026, from https://www.census.gov/programs-surveys/popest/data/data-sets.html

MLA 9

Population Estimates Program, county population by age and sex: median age (MEDIAN_AGE_TOT) on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage, Counties in South Dakota by median age on 1 July (US county estimates), 2017. U.S. Census Bureau, 25 June 2026, https://www.census.gov/programs-surveys/popest/data/data-sets.html. Invokely, https://invokely.ai/rankings/median-age-july-1-us-counties/south-dakota-counties?period=2017. Accessed 12 Oct. 2026.

Chicago (author-date)

U.S. Census Bureau. 2026. Population Estimates Program, county population by age and sex: median age (MEDIAN_AGE_TOT) on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage. Counties in South Dakota by median age on 1 July (US county estimates), 2017. Dataset. Accessed October 12, 2026. https://www.census.gov/programs-surveys/popest/data/data-sets.html. Also distributed by Invokely, https://invokely.ai/rankings/median-age-july-1-us-counties/south-dakota-counties?period=2017.

Harvard

U.S. Census Bureau (2026) Population Estimates Program, county population by age and sex: median age (MEDIAN_AGE_TOT) on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage, Counties in South Dakota by median age on 1 July (US county estimates), 2017 [Dataset]. Available at: https://www.census.gov/programs-surveys/popest/data/data-sets.html, via Invokely: https://invokely.ai/rankings/median-age-july-1-us-counties/south-dakota-counties?period=2017 (Accessed: 12 October 2026).

BibTeX

@misc{census_counties_in_south_dakota_2017,
  author = {{U.S. Census Bureau}},
  title = {{Population Estimates Program, county population by age and sex: median age (MEDIAN\_AGE\_TOT) on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage: Counties in South Dakota by median age on 1 July (US county estimates), 2017}},
  year = {2026},
  howpublished = {Data set},
  url = {https://www.census.gov/programs-surveys/popest/data/data-sets.html},
  urldate = {2026-10-12},
  note = {Accessed via Invokely, https://invokely.ai/rankings/median-age-july-1-us-counties/south-dakota-counties?period=2017. Publisher attribution: U.S. Census Bureau. Population Estimates Program, county population by age and sex: median age (MEDIAN\_AGE\_TOT) on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage. https://www.census.gov/programs-surveys/popest/data/data-sets.html. Retrieved 2026-10-12.},
}

RIS

TY  - DATA
AU  - U.S. Census Bureau
TI  - Population Estimates Program, county population by age and sex: median age (MEDIAN_AGE_TOT) on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage: Counties in South Dakota by median age on 1 July (US county estimates), 2017
PY  - 2026
DA  - 2026/06/25
PB  - U.S. Census Bureau
DB  - Invokely
UR  - https://www.census.gov/programs-surveys/popest/data/data-sets.html
L2  - https://invokely.ai/rankings/median-age-july-1-us-counties/south-dakota-counties?period=2017
Y2  - 2026/10/12
N1  - Accessed via Invokely, https://invokely.ai/rankings/median-age-july-1-us-counties/south-dakota-counties?period=2017.
N1  - Publisher attribution: U.S. Census Bureau. Population Estimates Program, county population by age and sex: median age (MEDIAN_AGE_TOT) on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage. https://www.census.gov/programs-surveys/popest/data/data-sets.html. Retrieved 2026-10-12.
ER  -

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Questions

Which county has the highest median age on 1 July (US county estimates)?

Custer County, with 55.1 years in 2017, according to the U.S. Census Bureau.

Which county has the lowest median age on 1 July (US county estimates)?

Todd County, with 24.2 years in 2017.

Where does this ranking come from?

Every value comes from one source and one period, so the places are comparable: U.S. Census Bureau, Population Estimates Program, county population by age and sex: median age (MEDIAN_AGE_TOT) on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage. Retrieved 2026-10-12.