A legislative proposal submitted to Congress estimates that codifying the name change from the Department of Defense to the “Department of War” would cost approximately $52 million, according to documents reviewed in reporting.

The 92-page proposal outlines expenses across multiple components of the defense establishment, with the largest share, about $44.6 million, allocated to defense agencies and field activities. Additional projected costs include $3.5 million for the military departments, $3 million for the Office of the Secretary of War and Washington Headquarters Services, and $400,000 for the Joint Staff, Combatant Commands, and the National Guard Bureau.

The document states that implementation efforts are already underway and that final cost figures will not be fully known until after the fiscal year 2026 changes are completed. It also notes that widespread updates would be required across federal law, administrative systems, and official records to reflect the new designation.

The proposal estimates roughly 7,600 statutory revisions, including the replacement of references to “Department of Defense” and “Secretary of Defense” with “Department of War” and “Secretary of War” throughout the U.S. Code and federal regulations.

The legislative package also includes related defense policy provisions, such as workforce authorities, depot maintenance funding adjustments, and equipment modification rules.

The change follows a September executive order issued under President Donald Trump directing the transition toward restoring the historic “Department of War” designation, according to reporting cited in the proposal.

The Department of Defense has already begun limited implementation steps, including updates to official websites, signage, and internal branding. The proposal also references ongoing administrative changes involving Defense Secretary Pete Hegseth in connection with the transition.

The Congressional Budget Office has previously estimated that total costs could reach as high as $125 million, depending on the scope and pace of implementation.

The measure has been introduced in Congress by Republican lawmakers in both chambers and remains subject to legislative consideration.