Days into the war with Iran and with no clear end in sight, questions have emerged about just how much Operation Epic Fury will cost US taxpayers.

The Pentagon hasn’t shared an estimate, and it has yet to ask Congress for a supplemental spending bill for the operation.

“This is highly unpredictable and so we won’t know the cost of it until it’s over.” said Lindsay Koshgarian, program director of the National Priorities Project at the Institute of Policy Studies, who said the conflict is “not necessary” and is taking away from other policies that could “make life more affordable for Americans.”

“The cost of the war in Iraq ended up being almost $3 trillion,” Koshgarian said. “So this could, this could be astronomical, easily.”

CNN has talked to think tanks and experts on government spending. Here’s a breakdown of what they told us:

More than $890 million a day

The war is costing about $891.4 million per day, according to a think tank based in Washington, DC, that analyzed the information the Pentagon has shared about targets it struck and the assets involved in the operation.

The Center for Strategic and International Studies predicts that the cost will decrease as the US shifts to “less expensive munitions” and as the drones and missiles launched by Iran declines.

“However, future costs will depend mostly on the intensity of operations and the effectiveness of Iranian retaliation,” CSIS added in its report.

Biggest cost drivers

Air, naval and ground operations will be the biggest expenses, according to the CSIS analysis.

Air operations are expected to cost $30 million per day, and the price tag for daily naval operations is around $15 million. Meanwhile, ground operations will cost $1.6 million each day.

These are the daily costs of the most expensive assets:

Air assets:

Tanker and cargo: $9 million
Carrier air wing: $5 million
Non-stealth fighter: $5 million
Stealth fighter: $5 million

Naval assets:

Aircraft carrier: $6 million
Destroyer: $5 million

Ground assets:

Artillery brigade: $1 million
National Guard battalion: less than $1 million

How it compares with last summer’s Iran strikes

The US’ strikes on Iran’s nuclear facilities in June 2025, called Operation Midnight Hammer, cost less than the first 100 hours of military operations that began when the US struck Iran early Saturday morning. Though last year’s operation lasted only about two-and-a-half hours.

According to CSIS, the first 100 hours of this war has cost $3.7 billion. Meanwhile, Costs of War at Brown University estimated that last year’s strikes cost between $2.04 to $2.26 billion. The project publishes research on US military spending and operations.

The major expenses during Midnight Hammer were the use of 40 MOP 30,000-pound bombs ($49 to $70 million); 7 B2 stealth bombers (between $31.75 to $37.8 million) and 24 Tomahawks (between $36 to $45.6 million), according to a report from Costs of War.

One expert says total cost of war could be up to $95 billion

It is unclear how long the operation will go on for, with the Trump administration offering shifting timelines — two weeks, four weeks, six weeks.

Defense Secretary Pete Hegseth said Wednesday, “We are just getting started,” and added that US forces will be “accelerating.”

Kent Smetters, faculty director of the Penn Wharton Budget Model, told CNN that a two-month war could cost between $40 and $95 billion, depending on whether the US puts boots on the ground and how quickly munitions are replenished. The group at the University of Pennsylvania says it provides non-partisan research on the fiscal impact of public policy.

“The type of investment we’re talking about today pales in comparison to” the cost of Iran obtaining and using a nuclear weapon, Smetters told CNN on Wednesday, which he said would be “trillions upon trillions of dollars of damage.” (CNN)

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