U.S. Operations Against Iran Cost Nearly $900 Million Per Day

As of early March 2026, the United States’ military operations against Iran have been estimated to cost approximately $891.4 million per day, based on an analysis of the first 100 hours of conflict. The figure was reported by the Washington‑based Centre for Strategic and International Studies (CSIS), which examined Pentagon data on targets struck, munitions expended and assets deployed during the opening phase of the campaign.

The analysis found that the total cost of the first 100 hours of the conflict reached about $3.7 billion, of which only a small portion had been included in existing U.S. defense budgets. Most of the expenditures will require additional funding from Congress if operations continue. The high daily costs are driven largely by the use of expensive weapons systems, precision munitions, and extensive air and naval operations.

CSIS researchers noted that unit costs for munitions, carrier operations, deployable systems, and other military assets contribute significantly to the daily expenditure, and that future costs will depend on the intensity of ongoing U.S. and allied actions, as well as Iranian responses. The estimate reflects direct military expenditures and does not include broader economic impacts such as disruptions to shipping in the Strait of Hormuz or longer‑term logistical costs.