The Pentagon hasn’t said how much the war with Iran is costing, but a new analysis from the Center for Strategic and International Studies, a bipartisan think tank, estimates that the first 100 hours of “Operation Epic Fury” cost $3.7 billion, or $891.4 million a day.
“Some of these costs are already budgeted, but most ($3.5 billion) are not,” the center’s Mark F. Cancian and Chris H. Park write in their analysis, published Thursday.
That estimate is in line with a preliminary one reportedly from the Pentagon, which The Atlantic said was $1 billion a day, citing an unnamed congressional official who spoke after a closed-door briefing for lawmakers this week by senior members of the Trump administration.
Rep. Brendan Boyle of Pennsylvania, the top Democrat on the House Budget Committee, requested yesterday that the Congressional Budget Office prepare an estimate that factors in both combat operations and other direct or indirect costs. In the meantime, Politico reported Friday that some Republican lawmakers have heard estimates that the Pentagon’s war spending could be as high as $2 billion a day. “Trump officials in private briefings have declined to give lawmakers any specific numbers, according to six congressional Republicans granted anonymity to describe the internal discussions,” Politico’s Meredith Lee Hill reported.
Another cost estimate provided to CNN by Kent Smetters of the Penn Wharton Budget Model projected that the price of a two-month war could be between $40 billion and $95 billion. Smetters told Fortune that the total economic cost of the strikes could range from $50 billion to as high as $210 billion when disruptions to trade, energy markets and other factors are considered. (He also noted that the cost of the war pales in comparison to the potential damage if Iran got and used a nuclear weapon.)
The CSIS report projects that the daily cost of the military operation could come down. “The shift of U.S. forces to less expensive munitions and the steep decline of Iranian drone and missile launches will drive costs down,” it says. “However, future costs will depend mostly on the intensity of operations and the effectiveness of Iranian retaliation.”
Even if the daily costs do drop, the CSIS report projects that unbudgeted expenses going forward “will be substantial” and that the Pentagon will need additional funding because the costs of the war will be “politically and operationally” challenging to offset through budget cuts elsewhere. Early cost estimates have led to reports that the Pentagon may request some $50 billion in supplemental funding for the war effort and related costs, such as replacing munitions stockpiles.
“The political challenge for the administration will be that any funding action will become a focal point for opposition to the war,” the CSIS report notes.
Money for munitions: Air operations cost about $125 million over the first 100 hours of the war and are expected to cost about $30 million for each additional day. The early cost of naval operations was about $65 million, with fleet operations incurring another $15 million a day at current size.
By far the largest cost of the war effort comes from munitions. “The United States has expended over 2,000 munitions of various types in the first 100 hours of the campaign,” the think tank report says, noting that U.S. Central Command has provided few specifics thus far. “Using past U.S. air campaigns as a guide, this analysis estimates it will cost $3.1 billion to replenish the U.S. munitions inventory on a like-for-like basis, with the costs increasing by $758.1 million a day.”
As the war has progressed and Iranian defenses have been degraded, the U.S. military can now use different types of munitions, shifting to ones that can be fired from closer to targets — which also cost less.
The CSIS report gives an example of the cost difference: While each Tomahawk cruise missile used in the opening phase of the war costs $3.6 million, equivalent bombs equipped with Joint Direct Attack Munition guidance kits cost $80,000 apiece. As a result, the new analysis predicts that “munitions costs will go down substantially as the U.S. strike operations switch to less expensive munitions.”
A costly planning problem? The Atlantic’s Simon Shuster and Nancy A. Youssef reported Thursday that the early days of the war revealed a costly gap in U.S. planning: “the United States and its allies used their most advanced anti-aircraft systems to shoot down swarms of cheap, easily replaceable Iranian drones.”
For example, the U.S. has been shooting missiles that cost millions of dollars apiece to bring down drones that might run $30,000 each.
That suggests a failure to adopt lessons in drone warfare from Ukraine’s fight against Russia. Ukraine has innovated less expensive ways to shoot down the Iranian-designed Shahed-136 drones launched at it by the thousands by Russia.
“Alternative means of defending against drone attacks—such as lasers—could bring down the cost of intercepting a drone from millions of dollars to a few bucks,” Schuster and Youssef write. “But until recently, the U.S. had invested more in its multilayered defense against drones, which involves interceptors, combat air patrols, electronic warfare, and short-range missiles. The U.S. was planning for—and bought weapons aimed at countering—threats from far-away targets such as China, not close-range foes such as Iran.”
Ukrainian President Volodymyr Zelensky said in a post on X this week that he had spoken with the leaders of the United Arab Emirates, Qatar, Jordan and Bahrain and would be speaking with others in the Middle East. He said he had agreed to provide Ukrainian expertise and aid in defending against drone strikes. “Our military possesses the necessary capabilities,” Zelensky wrote. “Ukrainian experts will operate on-site, and teams are already coordinating these efforts.”
What’s next: Congress is preparing for a funding request from the White House and the Pentagon. Some fiscal conservatives are already signaling that they’ll want any additional funding to be offset, while other lawmakers are reportedly eyeing other funding needs that could be included in a new spending package, from tariff relief for farmers to disaster aid.