2018 United States House of Representatives election in South Dakota

The 2018 United States House of Representatives election in South Dakota was held on November 6, to elect the U.S. representative for South Dakota's at-large congressional district. The election coincided with other statewide, legislative, and local elections.

Incumbent Republican U.S. Representative Kristi Noem did not run for a fifth term and instead ran successfully for Governor of South Dakota. This is the first open seat election since 2004 and the first time a male candidate was elected since 2002. This was the last U.S. House election in South Dakota until 2024 that a Democrat appeared on the November ballot.

Declared

 * Dusty Johnson, former chairman of the South Dakota Public Utilities Commission and former chief of staff to Governor Dennis Daugaard
 * Shantel Krebs, Secretary of State of South Dakota
 * Neal Tapio, state senator, businessman and former Trump campaign director for South Dakota.

Declined

 * Eric Terrell
 * Kristi Noem, incumbent U.S. Representative (running for governor)

Primary results
[[File:2018 SD-AL Republican primary.svg|thumb|Results by county: {{legend|#e27f7f|Johnson}}

{{legend|#ffc8cd|30–40%}}

{{legend|#ffb2b2|40–50%}}

{{legend|#e27f7f|50–60%}} {{legend|#ff9955|Krebs}}

{{legend|#ffcca9|30–40%}}

{{legend|#ffb580|40–50%}} {{legend|#5fd35f|Tapio}}

{{legend|#aae5aa|30–40%}}

{{legend|#87de87|40–50%}} ]]

Declared

 * Tim Bjorkman, former circuit court judge

Failed to file

 * Chris Martian, former IT professional

Declined

 * Shawn Bordeaux, state representative
 * Troy Heinert, state senator
 * J. R. LaPlante, former South Dakota Secretary of Tribal Relations and State House candidate in 2016
 * Stephanie Herseth Sandlin, former U.S. Representative
 * Mike Huether, Mayor of Sioux Falls (switched to Independent)
 * Brendan Johnson, former United States Attorney for the District of South Dakota
 * Billie Sutton, Minority Leader of the South Dakota Senate (running for governor)

Declared

 * George Hendrickson, former police officer

Declined

 * Mike Huether, Mayor of Sioux Falls

Counties that flipped from Republican to Democratic

 * Corson (Largest city: McLaughlin)