Maryland's 6th congressional district elects a representative to the United States House of Representatives from the northwest part of the state. The district comprises all of Garrett, Allegany, Frederick, and Washington counties as well as a portion of Montgomery County. David Trone (D) is its current representative.

Garrett County is the westernmost county of the U.S. state of Maryland completely within the Appalachian Mountains. As of the 2020 census, the population was 28,806, making it the third-least populous county in Maryland. Its county seat is Oakland. The county was named for John Work Garrett (1820–1884), president of the Baltimore and Ohio Railroad. Created from Allegany County in 1872, it was the last county to be formed in the state.