US War On Iran Costs $3.7 Billion In 100 Hours

Think tank analysis highlights soaring military expenses as conflict enters its first week

March 6, 2026: The United States has already spent an estimated $3.7 billion in the first 100 hours of its war against Iran, underscoring the enormous financial cost of the rapidly escalating conflict. The estimate, which averages nearly $900 million per day, comes from an analysis by the Washington-based Center for Strategic and International Studies (CSIS). Researchers said the massive expenditure is largely driven by the heavy use of advanced weapons systems and precision munitions during the opening phase of the campaign.

According to analysts Mark Cancian and Chris Park of CSIS, much of the spending was not originally included in the budget of the United States Department of Defense. Of the total cost, around $3.5 billion is believed to be unplanned expenditure, meaning the Pentagon may soon need to request additional funding from lawmakers. The potential request could create political pressure for the administration of Donald Trump, especially as domestic concerns about inflation, fuel prices and the cost of living continue to rise.

The CSIS report also estimates that more than 2,000 munitions were used during the first 100 hours of the operation, with replacement costs alone potentially reaching $3.1 billion. Analysts warn that expenses could climb even higher if the military campaign intensifies in the coming days, with expanded air operations and additional fighter squadrons being deployed. While air wars often slow after the initial phase, researchers cautioned that the ongoing conflict could continue to generate substantial and largely unbudgeted costs.