Full Count Act of 2018 This bill requires the Department of Commerce, beginning with the 2030 decennial census, to take appropriate measures to ensure that all Americans residing abroad on the census date are fully and accurately counted, and are properly attributed to their respective states and appropriate units of local government. Such measures shall include: use of the administrative records of a nongovernmental organization to enumerate members of such organization who are residing overseas as of the census date, completion of an international "Be Counted" form at a U.S. embassy by Americans residing overseas as of that date, and coordination and consultation with federal agencies to ensure that all appropriate databases involving Americans living overseas are referenced when compiling data for the census.