| County | Rank | Change (2020) ↓ | 2026 Pop. | 2020 Pop. |
|---|---|---|---|---|
| Lincoln County | 1 | 20.59% | 79,167 | 65,650 |
| Lawrence County | 2 | 16.88% | 30,209 | 25,847 |
| Mellette County | 3 | 16.07% | 2,225 | 1,917 |
| Hamlin County | 4 | 14.61% | 7,070 | 6,169 |
| Custer County | 5 | 14.46% | 9,538 | 8,333 |
| Brookings County | 6 | 11.99% | 38,456 | 34,338 |
| Minnehaha County | 7 | 9.25% | 215,966 | 197,688 |
| Turner County | 8 | 8.14% | 9,391 | 8,684 |
| Fall River County | 9 | 7.89% | 7,521 | 6,971 |
| Pennington County | 10 | 7.03% | 117,272 | 109,570 |
| McCook County | 11 | 6.63% | 6,047 | 5,671 |
| Clark County | 12 | 5.51% | 4,062 | 3,850 |
| Codington County | 13 | 5.29% | 29,854 | 28,353 |
| Butte County | 14 | 5.2% | 10,827 | 10,292 |
| Bon Homme County | 15 | 5.1% | 7,337 | 6,981 |
| Moody County | 16 | 5.03% | 6,665 | 6,346 |
| Dewey County | 17 | 4.46% | 5,456 | 5,223 |
| Harding County | 18 | 3.61% | 1,350 | 1,303 |
| Union County | 19 | 3.42% | 17,431 | 16,855 |
| Deuel County | 20 | 3.35% | 4,440 | 4,296 |
| Aurora County | 21 | 2.97% | 2,811 | 2,730 |
| Sanborn County | 22 | 2.96% | 2,399 | 2,330 |
| Beadle County | 23 | 2.94% | 19,726 | 19,162 |
| Marshall County | 24 | 2.7% | 4,417 | 4,301 |
| Douglas County | 25 | 2.61% | 2,908 | 2,834 |
| Campbell County | 26 | 2.39% | 1,411 | 1,378 |
| Sully County | 27 | 2.34% | 1,485 | 1,451 |
| Stanley County | 28 | 2.33% | 3,035 | 2,966 |
| Faulk County | 29 | 2.26% | 2,176 | 2,128 |
| Meade County | 30 | 2.17% | 30,547 | 29,897 |
| Yankton County | 31 | 1.73% | 23,693 | 23,291 |
| Kingsbury County | 32 | 1.69% | 5,288 | 5,200 |
| Perkins County | 33 | 1.56% | 2,873 | 2,829 |
| Day County | 34 | 1.45% | 5,521 | 5,442 |
| Tripp County | 35 | 1.28% | 5,678 | 5,606 |
| Davison County | 36 | 0.94% | 20,148 | 19,960 |
| Edmunds County | 37 | 0.78% | 4,013 | 3,982 |
| Ziebach County | 38 | 0.25% | 2,397 | 2,391 |
| Gregory County | 39 | 0.25% | 4,003 | 3,993 |
| Jones County | 40 | 0.11% | 928 | 927 |
| Brule County | 41 | 0.1% | 5,259 | 5,254 |
| Hutchinson County | 42 | 0.01% | 7,425 | 7,424 |
| Lyman County | 43 | -0.03% | 3,696 | 3,697 |
| Charles Mix County | 44 | -0.25% | 9,330 | 9,353 |
| Roberts County | 45 | -0.33% | 10,232 | 10,266 |
| Hand County | 46 | -0.64% | 3,124 | 3,144 |
| Lake County | 47 | -0.66% | 10,942 | 11,015 |
| Jerauld County | 48 | -0.67% | 1,633 | 1,644 |
| Miner County | 49 | -0.74% | 2,283 | 2,300 |
| Hughes County | 50 | -0.85% | 17,583 | 17,734 |
| Clay County | 51 | -0.88% | 14,872 | 15,004 |
| Grant County | 52 | -1.09% | 7,455 | 7,537 |
| McPherson County | 53 | -1.54% | 2,362 | 2,399 |
| Hanson County | 54 | -1.59% | 3,411 | 3,466 |
| Brown County | 55 | -1.91% | 37,501 | 38,230 |
| Walworth County | 56 | -1.91% | 5,190 | 5,291 |
| Bennett County | 57 | -2.62% | 3,308 | 3,397 |
| Corson County | 58 | -2.72% | 3,785 | 3,891 |
| Oglala Lakota County | 59 | -2.84% | 13,260 | 13,647 |
| Spink County | 60 | -2.95% | 6,156 | 6,343 |
| Haakon County | 61 | -4.76% | 1,780 | 1,869 |
| Potter County | 62 | -4.81% | 2,353 | 2,472 |
| Todd County | 63 | -5.4% | 8,813 | 9,316 |
| Hyde County | 64 | -6.01% | 1,173 | 1,248 |
| Jackson County | 65 | -6.54% | 2,616 | 2,799 |
| Buffalo County | 66 | -7.14% | 1,795 | 1,933 |
South Dakota's counties show varied growth patterns from 2020 to 2026. Lincoln County leads with 3.17% annualized growth, followed by Lawrence County (2.63%) and Mellette County (2.51%). The largest counties are Minnehaha County (215,966), Pennington County (117,272), and Lincoln County (79,167). Of the 66 counties in South Dakota, 42 are growing while 24 have experienced population decline. Overall, counties averaged 0.36% annualized growth, with total population growing by 1.01% annually.
-0.05
-0.025
0
0.025
0.05
0.075