Scott and the 24-year-old drummer met while touring with Tim McGraw in early 2010. People first reported the engagement Tuesday.
Scott is the second member of Lady A to end her single ways. Charles Kelley is married, leaving Dave Haywood as the lone available member of the Grammy-winning trio.
Lady A turned in the top-selling country album of 2010 with "Need You Now" and is preparing to release its follow-up, "Own The Night," due out Sept. 13.