Yorkville is a village in Belmont and Jefferson counties in the U.S. state of Ohio. The population was 968 at the 2020 census. Yorkville lies within two Metropolitan Statistical Areas; the Belmont County portion is part of the Wheeling metropolitan area, while the Jefferson County portion is part of the Weirton–Steubenville metropolitan area.

Belmont County is a county in the U.S. state of Ohio. As of the 2020 United States census, the population was 66,497. Its county seat is St. Clairsville, while its largest city is Martins Ferry. The county was created on September 7, 1801, and organized on November 7, 1801. It takes its name from the French for "beautiful mountain".