Cost of War with Iran Worries US as Expenses Reach $37.5 Billion and Continue to Rise

The war with Iran has so far cost the United States approximately $37.5 billion, US Defense Secretary Pete Hegseth said. However, experts say the actual cost could exceed that amount.

The statement came during a Senate budget hearing, where Democratic Senator Dick Durbin asked Hegseth whether he expected costs to rise further now that the ceasefire between the US and Iran is considered to have effectively ended.

Hegseth explained that the $37.5 billion estimate also includes projected spending through the end of the fiscal year, including the costs of feeding and supporting troops.

Independent estimates put the bill even higher. Experts calculated in March that the conflict was costing US taxpayers more than $890 million per day, while the Pentagon raised its overall estimate to $29 billion in May.

A preliminary analysis by the Center for Strategic and International Studies (CSIS) estimates that US Department of Defense spending has reached around $40 billion. This figure does not include some operational costs funded through the overall defense budget for fiscal year 2026.