The Trump Iran war cost is quickly becoming a major fiscal concern for policymakers and economists, with new estimates suggesting the conflict could add roughly $65 billion to the U.S. national debt in just 60 days.
Early Pentagon briefings to lawmakers indicate the first phase of the conflict has already generated significant spending. Officials reportedly told members of Congress in a closed meeting that the United States spent more than $11 billion during the first six days of military operations. That figure reflects direct operational expenses and does not include the cost of military assets and personnel deployed in advance of the initial strikes.
As the conflict continues, analysts say the financial burden could escalate rapidly.
“The meter is running”: Daily war costs approach $1 billion
Economists monitoring the conflict estimate that daily costs are approaching the billion dollar mark. Kent Smetters, faculty director of the Penn Wharton Budget Model, estimates the United States is currently spending about $800 million per day on operations related to the campaign.
Other analysts place the figure even higher. John Phillips, a British security and risk advisor, estimates the daily cost at roughly $1 billion once logistics, weapons systems, and support operations are fully accounted for.
If the pace continues and the conflict lasts roughly two months, Smetters estimates the Trump Iran war cost would total approximately $65 billion in new federal spending.
For a federal budget already strained by rising deficits and interest payments, the added expense would deepen existing fiscal pressures.
How the war spending could widen the U.S. deficit
The United States is already facing a widening fiscal gap. In its February outlook, the Congressional Budget Office projected a deficit of roughly $1.85 trillion for fiscal year 2026.
Government spending currently exceeds tax revenue by roughly one third, according to the forecast.
If the war runs for two months, economists estimate the additional $65 billion in spending would increase the deficit by about $66.4 billion once borrowing costs are included. That figure includes approximately $1.4 billion in additional interest payments associated with financing the spending.
The increase would push the projected deficit about 3.6 percent higher than current estimates, raising the deficit’s share of GDP from about 5.8 percent to roughly 6 percent.
Because the spending would be financed through borrowing, the additional debt would also generate recurring interest obligations in future federal budgets.
Tariff ruling adds another fiscal challenge
The financial impact of the conflict is unfolding alongside another budget setback for the administration.
Shortly before the first military strikes, the Supreme Court invalidated certain tariffs introduced during the Trump administration. Analysts say the ruling could significantly reduce government revenue from import duties.
According to estimates from the Committee for a Responsible Federal Budget, replacing the previous tariffs with a blanket 10 percent rate could reduce federal revenue by roughly $74 billion this year.
Combined with the projected war spending, the total fiscal impact could approach $139 billion. That would increase the projected deficit by roughly 7.5 percent relative to current forecasts.
Unlike war expenditures, which could eventually decline once the conflict ends, tariff-related revenue losses could become a recurring structural gap if the policy remains in place.
Oil market risks could extend economic fallout
Economists are also watching global energy markets closely as the conflict develops.
Diane Swonk, chief economist at KPMG, has warned that if key shipping routes such as the Strait of Hormuz remain disrupted, the conflict could persist for months. Extended instability in the region could send oil prices sharply higher.
Some forecasts suggest crude oil could rise above $130 per barrel under a prolonged disruption. In more extreme scenarios, analysts warn prices could approach $200 per barrel.
Higher energy prices would increase inflationary pressure across the U.S. economy while raising operating costs for businesses and households.
Even if the conflict lasts only several weeks longer, analysts say the Trump Iran war cost could compound fiscal challenges already facing Washington.
With the federal government carrying historically high debt levels and interest payments climbing, economists say the financial consequences of the conflict could extend well beyond the battlefield.
