The US war in Iran has cost approximately $37.5 billion so far, an increase of nearly $8 billion since May, the Pentagon reported on July 21, 2026 [1, 2, 3]. This figure covers certain war-related expenses and some projected costs through September 30 but does not clearly include all damages, such as to US military bases [1, 2].

The conflict began in late February 2026 after the collapse of a fragile ceasefire, with US and Israeli forces launching bombing campaigns following the killing of Iran's supreme leader Ali Khamenei [4, 5]. US military operations against Iran resumed in early July [1, 2].

Seventeen US service members have been killed and about 430 wounded in the conflict so far [2, 6, 7]. President Donald Trump has threatened to expand military targets to include energy plants, oil hubs, and underground nuclear sites, stating, "We will take out the mountain facility pretty soon" [2, 6].

On July 21, US Defense Secretary Pete Hegseth testified before the Senate Appropriations Committee, providing the updated $37.5 billion cost estimate and requesting $87 billion more in defense funding, $67 billion of which is earmarked for Middle East operations. Hegseth warned, "Without these funds, we face critical shortfalls that threaten our ability to also simply pay our service members, rapidly replenish equipment and munitions, and sustain vital operations without disruption." He added, "Every dollar appropriated would be used to build the lethality of US military forces and reinforce peace through strength." [1]

The US House of Representatives narrowly passed a $95 billion appropriations bill on July 22, which includes about $73 billion for Iran war funding [8, 9]. Some Democrats have criticized the rising cost and questioned the war's rationale. Senator Patty Murray said, "This war is now spiraling out of control again, the president is threatening escalation and war crimes and suggesting this could be another forever war." She also noted the president "has told us over 40 times now that a deal is near, and the war will be over soon. But now he is asking for US$70 billion more." [3] Representative Rosa DeLauro stated, "The American people do not want more endless, aimless, costly and deadly wars in the Middle East." [9]

The Pentagon’s request for additional funding is pending as US military operations continue in the Middle East amid uncertainty over the conflict’s trajectory [1, 4].