On May 29, 2019, Venters signed a minor league deal with the Washington Nationals. His contract was selected on June 25, 2019, and he was called up to the major leagues. Venters made 3 appearances for the Nationals, complying with a 0-1 record and a 5.40 ERA. On August 30, 2019, Venters underwent left shoulder surgery to repair a torn capsule, therefore ending his season. Overall in 2019, combined with both teams he played for, his ERA was 12.38 with 12 relief appearances. At the time of his absence, the Nationals finished the year with a 93-69 record, clinching a wild card spot, and eventually winning the 2019 World Series over the Astros.