USS Louisiana (SSBN-743) is the 18th and last ship of the United States Navy's Ohio class of nuclear-powered fleet ballistic missile submarines.

The contract for the construction of Louisiana was awarded on 19 December 1990 and her keel was laid down at the Electric Boat Division of General Dynamics in Groton, Connecticut, on 23 October 1992.

In the 1990s, with the end of the Cold War and the subsequent reorganization of U.S. military forces, a U.S. nuclear policy review recommended that the U.S. Navy reduce its inventory of Ohio-class fleet ballistic missile submarines from 18 to 14 by 2005.

[6] On 18 August 2016, Louisiana collided with USNS Eagleview, a submarine and special warfare support vessel, while conducting operations in the Strait of Juan de Fuca.

On 31 May 2007, United States Strategic Command announced that Louisiana had won the 2006 Omaha Trophy in the Submarine Ballistic Missile Command category, which recognizes excellence in the fleet and is presented annually to the ballistic missile submarine unit demonstrating the highest standards of performance; in order for Louisiana to receive the award, both her Blue Crew and Gold Crew had to achieve excellence in every category possible from loading weapons to tactical scenarios related to strategic warfare to sailor retention and crew morale, with selection for the award based on formal evaluations, meritorious achievement, safety, and other factors such as community involvement and humanitarian actions.

Louisiana was specifically recognized for meritorious service and superior performance across the spectrum of strategic submarine operations, setting fleet standards of excellence for administration, engineering, supply, personnel programs, and community support.

The symbolism of the crest reminds both crews of their bond to the people and history of Louisiana, as well as the tradition of the naval veterans who have served aboard ships of the same name.

The bow-on perspective of the modern Ohio-class submarine is meant to be striking, bold, and steadfast in its appearance, serving as a warning of Louisiana's resolute commitment to defending freedom.