The United States spent an estimated $33.4 billion on its military campaign against Iran between February 28 and June 30, with more than $22 billion going towards weapons and ammunition, according to a report by the US Department of Defense inspector general. The assessment has also highlighted significant pressure on American weapons inventories and identified bottlenecks in the defence industry that could complicate efforts to replenish some critical munitions.
The report provides one of the first detailed assessments of the financial and military impact of the US operation, known as Operation Epic Fury. Of the estimated $33.4 billion expenditure, around $22.3 billion was attributed to munitions used during the conflict. A further $7.4 billion was linked to other expenses associated with the operation, while military equipment losses were estimated at about $3.7 billion. The figures do not include the cost of repairing infrastructure damaged during the fighting.
The inspector general’s findings point to the extensive use of American weapons during the campaign and the resulting strain on strategic stockpiles. The report said the consumption of munitions had resulted in “strategic inventory shortfalls” and exposed bottlenecks in the US defence industrial base responsible for replacing the weapons.
US acquisition officials told investigators that measures were being taken to accelerate procurement and reduce the time required to manufacture and deliver munitions. The Pentagon is also working to build reserves of important raw materials, components and selected weapons so that supplies can be restored more quickly during future military contingencies.
The assessment also detailed losses and damage involving American military equipment. At least four F-15E fighter aircraft were destroyed during the period covered by the report, while an A-10 ground-attack aircraft was also lost. Seven KC-135 aerial-refuelling aircraft were damaged or destroyed, along with seven helicopters and more than 30 unmanned drones. An F-35A fighter aircraft was also damaged by Iranian fire, marking a significant incident involving the advanced aircraft.
The conflict also resulted in extensive damage to US military facilities across the Middle East. Hundreds of buildings and other structures at American bases were reported to have been damaged or destroyed. US diplomatic facilities in countries including Iraq, Kuwait, Saudi Arabia and the United Arab Emirates also suffered damage, with the physical losses at diplomatic facilities estimated at about $184 million.
The Pentagon’s findings come amid an ongoing debate in Washington over the condition of US military stockpiles. President Donald Trump had previously dismissed concerns about American ammunition supplies, saying the country possessed large quantities of munitions. The inspector general’s report, however, specifically identified shortages in strategic inventories and difficulties in rapidly replacing some of the weapons consumed during the operation.
The findings have also raised questions about the capacity of the US defence industry to increase production quickly in response to sustained military demand. The report identified constraints involving areas such as rocket motors, explosives and specialised labour, potentially affecting the speed at which depleted stocks can be restored.
The $33.4 billion estimate covers only the period through the end of June. A subsequent estimate reported on September 19 put the overall US military cost of the Iran conflict at $43.6 billion as of September 3, indicating that the financial burden continued to rise after the period examined in the earlier inspector general assessment.
