US Spent $38 Billion on War in Iran

The report, published on 15 September, indicates that the costs are mainly linked to replacing ammunition and equipment lost in combat, increased flight hours, military operations and higher fuel expenses.

The estimate covers costs incurred by the US Department of Defense since combat operations against Iran began in February under what has been designated Operation Epic Fury.

According to the CBO, spending could continue to rise as long as the conflict persists. If the intensity of the fighting remains relatively low, similar to levels recorded in May and June, each additional month could cost around $2 billion.

If fighting returns to levels seen in July, monthly costs could rise to around $3 billion. A further military escalation could push spending even higher.

The CBO cautioned, however, that the figures are subject to “considerable uncertainty” because the Department of Defense did not respond to requests for information made during the preparation of the report. The agency therefore relied on government databases and publicly available reports.

In June, the US administration requested $87.6 billion in supplemental funding from Congress, of which $67.1 billion would go to the Department of Defense for conflict-related expenses. According to the CBO, around $42.3 billion of that request appears to be directly linked to military operations.

Impact on Prices

In addition to military spending, the CBO said the conflict is also putting pressure on the US economy through higher energy prices.

Reduced shipments of oil and natural gas through the Strait of Hormuz, combined with disruptions to shipping in the Red Sea, have contributed to higher international energy and refined petroleum product prices.

The agency estimates that, by the first quarter of 2027, inflation measured by the Personal Consumption Expenditures price index could be 0.5 percentage points higher than projected in February 2026 because of the effects associated with the conflict.

The CBO also warned that the heavy use of missile defence interceptors during military operations could leave the United States with reduced stocks of these systems for several years.