We, the National Marine Fisheries Service (NMFS), issue a final rule designating critical habitat for the Southern Resident killer whale (Orcinus orca) distinct population segment (DPS). Three specific areas are designated, (1) the Summer Core Area in Haro Strait and waters around the San Juan Islands; (2) Puget Sound; and (3) the Strait of Juan de Fuca, which comprise approximately 2,560 square miles (6,630 sq km) of marine habitat. We considered the economic impacts and impacts to national security, and concluded the benefits of exclusion of 18 military sites, comprising approximately 112 square miles (291 sq km), outweighed the benefits of inclusion because of national security impacts. We solicited comments from the public on all aspects of the proposed rule. An economic analysis, biological report, and Endangered Species Act (ESA) report were available for comment along with the proposed rule. The supporting documents have been finalized in support of the final critical habitat designation.