Missouri's 6th congressional district takes in a large swath of land in northern Missouri, stretching across nearly the entire length of the state from Kansas to Illinois. Its largest voting population is centered in the northern portion of the Kansas City metropolitan area and the town of St. Joseph. The district includes all of Kansas City north of the Missouri River (including Kansas City International Airport).
The district takes in all or parts of the following counties: Andrew, Atchison, Buchanan, Caldwell, Carroll, Chariton, Clay, Clinton, Cooper, Daviess, De Kalb, Gentry, Grundy, Harrison, Holt, Howard, Jackson, Linn, Livingston, Mercer, Nodaway, Platte, Putnam, Ray, Schuyler, Sullivan, Worth.
Notable representatives from the district include governors John Smith Phelps and Austin A. King as well as Kansas City Mayor Robert T. Van Horn. In 1976, Jerry Litton was killed on election night as he flew to a victory party after winning the Democratic nomination for United States Senate. The visitors center at Smithville Lake is named in Litton's memory.