These tables are historical listings of state senators who served in the South Dakota Senate from statehood in 1889 until the present.
| Democratic | Fusion | Independent | Non-Partisan | Populist | Republican |
45 senators elected from 41 districts. Senators were elected from single-member districts, with five counties each electing two at-large senators. The number of senators was reduced to 43 senators from 1893 to 1899. A 42nd District was added in 1909.
| District | Seats | Years | County |
|---|---|---|---|
| 9th | 2 | 1889–1909 | Minnehaha |
| 10th | 2 | 1909–1939 | |
| 30th | 2 | 1889–1893 | Spink |
| 32nd | 2 | 1899–1909 | Day |
| 33rd | 2 | 1909–1939 | Brown |
| 35th | 2 | 1909–1939 | |
| 38th | 2 | 1889–1893; 1899–1909 | Lawrence |
| 39th | 2 | 1909–1939 |
35 senators elected from 33 districts. Three counties each elected two at-large senators.
| District | Seats | Years | County |
|---|---|---|---|
| 7th | 2 | 1939–1967 | Minnehaha |
| 22nd | 2 | 1939–1961 | Brown |
| 28th | 2 | 1963–1967 | Pennington |
35 senators elected from 35 single-member districts. From 1967 to 1973, there were only 29 districts, with three counties each electing more than one at-large member. District 29 was eliminated from 1973 to 1985, when it became District 11's fifth at-large seat. In 1985, all remaining multi-member districts were eliminated, establishing the current 35 single-member districts.
| District | Seats | Years | County |
|---|---|---|---|
| 2nd | 2 | 1967–1985 | Brown |
| 11th | 4 | 1967–1973 | Minnehaha |
| 5 | 1973–1985 | ||
| 28th | 3 | 1967–1973 | Pennington |
| 27th | 3 | 1973–1985 |