CBO: Layered Counter-drone Defense Would Cost About $74 Million to Harden One U.S. Base, $5 Million a Year to Support

Hardening a single representative U.S. military base against small drones would cost about $74 million upfront and another $5 million a year to support, according to a new estimate from the Congressional Budget Office that gives Congress a concrete price benchmark for a fast-growing security problem.

The estimate appears in CBO’s July 9 report, “Options to Counter Small Unmanned Aircraft Systems,” prepared at the request of the Subcommittee on Tactical Air and Land Forces of the House Armed Services Committee. CBO said it was not endorsing any particular course of action. Instead, it evaluated five options for defending military installations against small unmanned aircraft systems, or sUAS.

CBO’s benchmark is not a universal price tag for every base. The office modeled a representative military installation measuring 5 miles by 5 miles, then assessed what it would cost to defend that site with different mixes of detection and defeat systems.

Its most comprehensive approach, Option 5, uses what CBO called a layered defense. That package combines all the systems included in the other options: four radars, 12 radio-frequency signal detection and defeat systems, four kinetic interceptors, 16 handheld counter-UAS defeat systems and a command-and-control system to tie them together.

The logic is that no single tool catches every drone. The report reviews major ways to detect small drones, including radar, radio-frequency sensors that pick up control links, acoustic systems and cameras. It also examines ways to stop them, including nets or entanglement systems, radio-frequency defeat and kinetic interceptors. Directed-energy systems such as lasers and high-power microwaves, CBO said, are still under development.

CBO’s core conclusion was that “a layered set of multiple detection and defeat systems would offset individual systems’ limitations and maximize protection.” For that representative installation, the office said, “CBO estimates that it would cost about $74 million to equip one representative installation with a layered defense and $5 million a year to support it.”

That annual support figure comes with a major caveat: It does not include personnel costs. CBO said operating costs would rise substantially if additional troops were assigned to run the systems. As one example, it said adding an Army company of 66 soldiers would cost about $6.6 million per year.

The numbers rise quickly at scale. CBO said the costs would increase roughly linearly across installations, meaning 100 installations equipped with the full three-layer defense would require about $7.4 billion in acquisition costs and $500 million a year to operate. Those estimates also do not include the Pentagon’s broader counter-drone research bill. CBO said the Defense Department already spends more than $300 million annually on counter-UAS research, development, testing and evaluation, and those costs were excluded from the report.

The report lands amid growing concern about drone activity near U.S. military sites. CBO said the use of small drones has proliferated since Russia’s full-scale invasion of Ukraine in 2022, and that drones of unknown origin have been observed over U.S. military installations and other important sites.

Military leaders have also been sounding alarms publicly. Gen. Gregory M. Guillot, who leads U.S. Northern Command and North American Aerospace Defense Command, told lawmakers in testimony reported by DoD News in February 2025: “There were 350 UAS detections over a total 100 different U.S. military installations reported last year.”

CBO also drew a clear boundary around what its analysis does not cover. “This analysis does not examine the legal and operational issues concerning an installation commander’s authority to engage UASs in the United States, nor does it assess the systems and tactics that could be used to defend mobile military forces,” the report said.