Defense Primer: Department of the Navy

Defense Primer: Department of the Navy

Defense Primer: Department of the Navy

Updated January 16, 2026 (IF10484)

One Military Department with Two Military Services

The Department of the Navy (DON) is a single military department that includes two military services—the Navy and the Marine Corps. As such, DON has a single civilian leader, the Secretary of the Navy, and two four-star military service chiefs—an admiral whose title is the Chief of Naval Operations (CNO), and a general whose title is the Commandant of the Marine Corps. Although the title "Secretary of the Navy" includes only the term "Navy," the secretary serves as the civilian leader for both the Navy and Marine Corps. The CNO and the Commandant of the Marine Corps are members of the Joint Chiefs of Staff (JCS). As of January 16, 2026, the Secretary of the Navy is John Phelan, the CNO is Admiral Daryl Caudle, and the Commandant of the Marine Corps is General Eric Smith.

"Naval" Refers to Both the Navy and Marine Corps

Although the term "naval" is often used to refer specifically to the Navy, it more properly refers to both the Navy and Marine Corps, because both the Navy and Marine Corps are naval services. Even though the Marine Corps sometimes operates for extended periods as a land fighting force (as it did, for example, in Afghanistan and Iraq), and is often thought of as the country's second land army, it nevertheless is, by law, a naval service. 10 U.S.C. 8001(a)(3) states that "The term 'member of the naval service' means a person appointed or enlisted in, or inducted or conscripted into, the Navy or the Marine Corps." DON officials sometimes refer to the two services as the Navy-Marine Corps team. See also the section below entitled "The Naval Service."

"Navy" in DOD Budget Documents Can Mean DON

DOD budget documents that divide the DOD budget into four military departments often label those departments as Army, Navy, Air Force, and Defense-Wide. In using data from such documents, it is important to remember that the category called "Navy" in these cases refers to the Department of the Navy, and thus includes funding for both the Navy and Marine Corps.

"Blue Dollars" and "Green Dollars" in DON Budget

People who work with the DON budget sometimes refer to "blue dollars," meaning funding in the DON budget for the Navy, and "green dollars," meaning funding in the DON budget for the Marine Corps. Of the more than two dozen appropriation accounts that form DON's budget, many contain funding specifically for either the Navy or Marine Corps. For example, the Operation and Maintenance, Navy (OMN), appropriation account contains operation and maintenance funding primarily for the Navy, while the Operation and Maintenance, Marine Corps (OMMC), appropriation account contains operation and maintenance funding for the Marine Corps.

A few DON appropriation accounts include funding for both the Navy and Marine Corps, even though their titles refer only to the Navy. For example, the Aircraft Procurement, Navy (APN) appropriation account funds the procurement of both Navy and Marine Corps aircraft, and the Research, Development, Test, and Evaluation, Navy (RDTEN) account includes research and development funding for both the Navy and Marine Corps.

The Navy's shipbuilding account, known formally as the Shipbuilding and Conversion, Navy (SCN) appropriation account, funds the procurement of various types of ships, including amphibious ships. Although amphibious ships are Navy ships operated by Navy crews, the primary function of amphibious ships is to transport Marine Corps personnel and equipment and support Marine Corps ship-to-shore movements and Marine Corps operations ashore. The Navy's amphibious ships are sometimes referred to informally as the "Gator Navy," a shortening of the term alligator.

DON Budget

The Department of Defense (DOD) characterizes its FY2026 budget submission as including funding requested from two sources: H.R. 1/P.L. 119-21 of July 4, 2025, the One Big Beautiful Bill Act (aka reconciliation bill, aka megabill), and the FY2026 DOD Appropriations Act. DON states that its FY2026 budget submission includes about $43.3 billion requested for H.R. 1/P.L. 119-21, and about $248.9 billion requested for the FY2026 DOD Appropriations Act, for a combined requested total of about $292.2 billion. The $43.3 billion requested for H.R. 1/P.L. 119-21 equates to about 14.8% of the combined total of about $292.2 billion.

Within the requested total of about $292.2 billion, about $235.0 billion (80.4%) is for the Navy and the rest is for the Marine Corps. In terms of appropriation groups, within the $292.2 billion, about $61.9 billion (22.7%) is for military personnel, $93.7 billion (32.1%) is for operations and maintenance, $95.3 billion (32.6%) is for procurement, $29.2 billion (10.0%) is for research and development, $7.4 billion (2.5%) is for military construction, and $0.4 billion (0.1%) is for revolving funds.

Within the figure of about $43.3 billion requested for DON for H.R. 1/P.L. 119-21, about $41.0 billion (94.7%) is for the Navy, and more specifically, about $26.5 billion (61.3%) is requested for the Navy's shipbuilding account, known formally as the Shipbuilding and Conversion, Navy (SCN) account.

DON Personnel

DON's FY2026 budget submission requests a total of 830,089 personnel, including 516,900 active-duty uniformed personnel, 91,100 reserve personnel, and 222,089 civilian personnel. The submission requested a total of 603,219 Navy personnel (344,600 active-duty, 57,500 reserve, and 201,119 civilian), and a total of 226,870 Marine Corps personnel (172,300 active-duty, 33,600 reserve, and 20,970 civilian).

Coast Guard in Relation to DON

Unlike DON, which is covered (along with other parts of DOD) in the U.S. Code primarily in Title 10, the Coast Guard is part of the Department of Homeland Security (DHS) and is covered primarily in Title 14. Even though the Coast Guard is not part of DOD, Title 14 states that the Coast Guard "shall be a military service and a branch of the armed forces of the United States at all times." (14 U.S.C. 101) Title 14 states that the Coast Guard "shall be a service in the Department of Homeland Security, except when operating as a service in the Navy" (14 U.S.C. 103(a)), and that

Upon the declaration of war if Congress so directs in the declaration or when the President directs, the Coast Guard shall operate as a service in the Navy, and shall so continue until the President, by Executive order, transfers the Coast Guard back to the Department of Homeland Security. While operating as a service in the Navy, the Coast Guard shall be subject to the orders of the Secretary of the Navy, who may order changes in Coast Guard operations to render them uniform, to the extent such Secretary deems advisable, with Navy operations." (14 U.S.C. 103(b))

The last time the Coast Guard operated as a service in the Navy was during World War II. The possibility that the Coast Guard might at some point operate as a service in the Navy is why legislation concerning the Coast Guard sometimes uses phrases such as "the Secretary of the Department in which the Coast Guard is operating."

The four-star admiral who heads the Coast Guard, called the Commandant of the Coast Guard, is not a member of the JCS. As of January 16, 2026, the Commandant of the Coast Guard is Admiral Kevin E. Lunday. Unlike the DOD services, the Coast Guard is not only a military service and a branch of the Armed Forces, but also a law enforcement agency. For this reason, Navy ships whose operations create a distinct possibility of encountering potential law enforcement situations (such as those relating to drug interdiction, migrant interdiction, and enforcement of fisheries laws) sometimes embark detachments of Coast Guard personnel.

The Coast Guard's budget is funded primarily through the annual DHS appropriations act. DON's budget sometimes includes small amounts of funding to support the Coast Guard's national defense mission. In addition, the procurement of one of the Coast Guard's polar icebreakers (Healy) was funded primarily with FY1990 SCN funding, 33 of the Coast Guard's 49 Island-class 110-foot patrol boats were procured under a Navy contract that included FY1990 SCN funding, and $300 million of the funding that has been appropriated for the Coast Guard's new Polar Security Cutter (aka polar icebreaker) program was appropriated through the SCN account ($150 million each in FY2017 and FY2018). The Coast Guard's reserve end strength (but not its active end strength) is authorized in the annual National Defense Authorization Act (NDAA).

The Navy and Coast Guard have mechanisms, including a Navy and Coast Guard (NAVGARD) Board, to coordinate matters of joint interest. The Navy and Coast Guard on at least three occasions (2002, 2006, and 2013) have issued National Fleet policy statements on the coordination of their procurement and operational activities.

The Sea Services and the Naval Service

The Navy, Marine Corps, and Coast Guard are sometimes referred to collectively as the sea services. A tri-service strategy document released in December 2020, entitled Advantage at Sea, Prevailing with Integrated All-Domain Naval Power, states that the three services are "collectively known as the Naval Service," and defines the term naval service in its glossary as meaning the three services. The April 2020 edition of a tri-service doctrine publication, Naval Doctrine Publication 1, Naval Warfare, states "The United States Navy, the United States Marine Corps, and the United States Coast Guard collectively form the nation's Naval Service." The Coast Guard, however, is not frequently referred to as a naval service in annual Navy or Coast Guard documents submitted to Congress, and the U.S. Code does not specifically define the Coast Guard as a naval service (as opposed to a military service or a branch of the Armed Forces) in 10 U.S.C. 8001(a)(3), 14 U.S.C. 101, 14 U.S.C. 103(a), or other provisions.

The three services in recent years have from to time issued joint maritime strategy documents, including, most recently, the previously mentioned document entitled Advantage at Sea, Prevailing with Integrated All-Domain Naval Power.

Relevant Statutes

Title 10, U.S. Code, Subtitle C – Navy and Marine Corps

Title 14, U.S. Code, Chapter 1 – Establishment and Duties of the Coast Guard

Other Resources

Department of the Navy, Highlights of the Department of the Navy FY 2026 Budget, 2024, 144 pp.

Department of Homeland Security, U.S. Coast Guard, Budget Overview, Fiscal Year 2026, Congressional Justification, undated, 174 pp.

U.S. Navy, U.S. Marine Corps, U.S. Coast Guard, Advantage at Sea, Prevailing with Integrated All-Domain Naval Power, December 2020, 29 pp.