NTIA submits this Sixth Interim Progress Report to describe progress toward achieving the Administration’s directive to identify and make available 500 megahertz of spectrum for licensed and unlicensed wireless broadband services within ten years, while assuring the protection of vital government operations that rely on spectrum. This report covers October 1, 2014 through September 30, 2015 (FY15). As of September 2015, NTIA and the FCC had made significant progress toward the goal by making a total of 245 megahertz of spectrum available for wireless broadband technologies, including 165 megahertz during FY15. This spectrum is comprised of 140 megahertz from federal or shared bands and 105 megahertz from non-federal bands. Accomplishments to date are a result of the continued collaboration between NTIA, the FCC, the federal agencies, industry, and other stakeholders.