SD · 2026 Census Gazetteer

South Dakota counties by area

Official, comparable measurements for 66 counties and county equivalents.

Source fields preservedGEOID · ALAND · AWATER

County equivalents66

Combined land75,809.3 mi²

Combined water1,306.6 mi²

Largest by landMeade County

Understanding South Dakota’s county areas

The land-area range runs from Clay County at 412 mi² to Meade County at 3,470.9 mi². The largest has 8.4 times the land area of the smallest and accounts for 4.6% of the combined county land in South Dakota.

The median county-equivalent land area is 909.3 mi², above the national median of 604.5 mi². The median describes the middle of the county size distribution; it does not describe how people or development are distributed. A state with a few very large counties can have a much smaller median than its largest entry suggests.

Where water changes the picture

Dewey County has the most assigned water area, at 142.9 mi². Hughes County has the highest water share, with water making up 7.4% of its total area. Water area and water percentage answer different questions: the first measures an amount, while the second measures the mix of land and water.

Across all 66 entries, water accounts for 1.7% of the combined total area. This is calculated from the summed land and water measurements, rather than averaging county percentages, which would give each small and large county equal weight.

Compare the largest and smallest county equivalents in South Dakota to see land, water, and total area on the same scale.

These calculations use the 2026 Census county records listed below. County-equivalent boundaries vary between states; area alone does not measure population, density, or usable land. See coverage and calculation rules.

Complete area table

Sorted from largest to smallest land area.

#	County / equivalent	Land	Water	Water share
1	Meade CountyGEOID 46093	3,470.9 mi²	11.9 mi²	0.3%
2	Perkins CountyGEOID 46105	2,870.5 mi²	19.5 mi²	0.7%
3	Pennington CountyGEOID 46103	2,776.8 mi²	7.7 mi²	0.3%
4	Harding CountyGEOID 46063	2,671.6 mi²	6.5 mi²	0.2%
5	Corson CountyGEOID 46031	2,469.7 mi²	60 mi²	2.4%
6	Dewey CountyGEOID 46041	2,302.4 mi²	142.9 mi²	5.8%
7	Butte CountyGEOID 46019	2,250 mi²	16.5 mi²	0.7%
8	Oglala Lakota CountyGEOID 46102	2,093.6 mi²	2.8 mi²	0.1%
9	Ziebach CountyGEOID 46137	1,961.2 mi²	9.3 mi²	0.5%
10	Jackson CountyGEOID 46071	1,863.9 mi²	7.4 mi²	0.4%
11	Haakon CountyGEOID 46055	1,810.5 mi²	16.4 mi²	0.9%
12	Fall River CountyGEOID 46047	1,739.9 mi²	9.3 mi²	0.5%
13	Brown CountyGEOID 46013	1,713 mi²	17.9 mi²	1%
14	Lyman CountyGEOID 46085	1,642.3 mi²	64.6 mi²	3.8%
15	Tripp CountyGEOID 46123	1,612.3 mi²	5.2 mi²	0.3%
16	Custer CountyGEOID 46033	1,556.9 mi²	2.1 mi²	0.1%
17	Spink CountyGEOID 46115	1,503.5 mi²	6.2 mi²	0.4%
18	Stanley CountyGEOID 46117	1,444.4 mi²	72.7 mi²	4.8%
19	Hand CountyGEOID 46059	1,436.6 mi²	3.6 mi²	0.2%
20	Todd CountyGEOID 46121	1,388.6 mi²	2.3 mi²	0.2%
21	Mellette CountyGEOID 46095	1,307.3 mi²	3.6 mi²	0.3%
22	Beadle CountyGEOID 46005	1,258.7 mi²	6.1 mi²	0.5%
23	Bennett CountyGEOID 46007	1,184.6 mi²	5.8 mi²	0.5%
24	McPherson CountyGEOID 46089	1,136.7 mi²	14.9 mi²	1.3%
25	Edmunds CountyGEOID 46045	1,126 mi²	25.1 mi²	2.2%
26	Roberts CountyGEOID 46109	1,101.1 mi²	34.7 mi²	3.1%
27	Charles Mix CountyGEOID 46023	1,097.1 mi²	53.1 mi²	4.6%
28	Day CountyGEOID 46037	1,028.5 mi²	62.6 mi²	5.7%
29	Gregory CountyGEOID 46053	1,015 mi²	38.6 mi²	3.7%
30	Sully CountyGEOID 46119	1,006.7 mi²	63.5 mi²	5.9%
31	Faulk CountyGEOID 46049	981.7 mi²	24.2 mi²	2.4%
32	Jones CountyGEOID 46075	969.7 mi²	1.2 mi²	0.1%
33	Clark CountyGEOID 46025	957.5 mi²	10 mi²	1%
34	Potter CountyGEOID 46107	861.1 mi²	37.5 mi²	4.2%
35	Hyde CountyGEOID 46069	860.6 mi²	5.6 mi²	0.6%
36	Marshall CountyGEOID 46091	838.1 mi²	48.1 mi²	5.4%
37	Kingsbury CountyGEOID 46077	832.2 mi²	31.5 mi²	3.6%
38	Brule CountyGEOID 46015	817.2 mi²	29.3 mi²	3.5%
39	Hutchinson CountyGEOID 46067	813 mi²	1.4 mi²	0.2%
40	Minnehaha CountyGEOID 46099	806.9 mi²	7 mi²	0.9%
41	Lawrence CountyGEOID 46081	800.1 mi²	0.3 mi²	0%
42	Brookings CountyGEOID 46011	792.2 mi²	12.7 mi²	1.6%
43	Hughes CountyGEOID 46065	741.5 mi²	59.2 mi²	7.4%
44	Campbell CountyGEOID 46021	733.8 mi²	37.1 mi²	4.8%
45	Aurora CountyGEOID 46003	708.5 mi²	4.3 mi²	0.6%
46	Walworth CountyGEOID 46129	707.5 mi²	37.2 mi²	5%
47	Codington CountyGEOID 46029	687.6 mi²	29.6 mi²	4.1%
48	Grant CountyGEOID 46051	681.4 mi²	6.1 mi²	0.9%
49	Deuel CountyGEOID 46039	622.7 mi²	13.9 mi²	2.2%
50	Turner CountyGEOID 46125	617.1 mi²	0.6 mi²	0.1%
51	Lincoln CountyGEOID 46083	577.3 mi²	0.5 mi²	0.1%
52	McCook CountyGEOID 46087	574.2 mi²	2.7 mi²	0.5%
53	Miner CountyGEOID 46097	570.2 mi²	1.8 mi²	0.3%
54	Sanborn CountyGEOID 46111	569.2 mi²	1.2 mi²	0.2%
55	Bon Homme CountyGEOID 46009	563.5 mi²	18.1 mi²	3.1%
56	Lake CountyGEOID 46079	562.9 mi²	12.3 mi²	2.1%
57	Jerauld CountyGEOID 46073	526.1 mi²	6.5 mi²	1.2%
58	Yankton CountyGEOID 46135	521.2 mi²	11.1 mi²	2.1%
59	Moody CountyGEOID 46101	519.4 mi²	1.4 mi²	0.3%
60	Hamlin CountyGEOID 46057	507.1 mi²	31 mi²	5.8%
61	Buffalo CountyGEOID 46017	471.4 mi²	16.4 mi²	3.4%
62	Union CountyGEOID 46127	462 mi²	5.2 mi²	1.1%
63	Davison CountyGEOID 46035	435.6 mi²	1.3 mi²	0.3%
64	Hanson CountyGEOID 46061	434.6 mi²	0.8 mi²	0.2%
65	Douglas CountyGEOID 46043	431.8 mi²	1.9 mi²	0.4%
66	Clay CountyGEOID 46027	412 mi²	5.4 mi²	1.3%

How to read this table. Land and water areas are Census statistical measurements in square miles. Adding county rows can differ slightly from separately published state totals because of rounding and geographic treatment.