The top Democrat on the U.S. House Budget Committee sent a letter to the nonpartisan Congressional Budget Office on Thursday, asking its experts to determine how much the war in Iran could cost.
“The Constitution grants Congress both the power of the purse and the responsibility of declaring war,” wrote U.S. Rep. Brendan Boyle, who represents Philadelphia. “A timely and comprehensive estimate from CBO will support Congress in the conduct of its constitutional responsibilities.
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“Congress should ensure we are spending taxpayer dollars to improve the quality of life for the American people, not paying for another endless war in the Middle East.” ‘
Boyle asked the CBO to detail how much the war would cost “under several scenarios, including scenarios of the war lasting longer than 4 to 5 weeks and deploying U.S. troops on the ground in Iran.”
He requested the CBO to look at possible unintended costs of the war as well, such as how would “moving an aircraft carrier from near Taiwan to off the coast of Iran impact the United States responding to potential Chinese aggression?”
And Boyle asked the CBO to detail how the war in Iran could affect prices within the United States.
The Trump administration has not publicly disclosed how much it’s spent on the war or what it expects the total price tag will be for what is dubbed Operation Epic Fury. A spokesperson for the Department of Defense told States Newsroom, when asked about costs, that they “have nothing to provide on this at this time.”
President Donald Trump said during an afternoon appearance at the White House that Iranian leaders called to try to negotiate an end to the war, but didn’t say if he would begin talks.
“They’re calling. They’re saying, ‘How do we make a deal?’ I said you’re being a little bit late,” Trump said. “And we want to fight now more than they do.”
Trump launched the war on Saturday, killing Iran Supreme Leader Ayatollah Ali Khamenei and several other top officials in that country’s government. The U.S. and Israeli militaries have continued bombing in the days since.
Trump has said he expects the war could last between four and six weeks, or go longer. He hasn’t ruled out sending U.S. ground troops into Iran, though several Republican lawmakers left classified briefings earlier this week saying boots on the ground would be a step too far.
Congress has not approved an Authorization for Use of Military Force or declared war against Iran, with both Speaker Mike Johnson (R-La.) and Senate Majority Leader John Thune (R-S.D.) saying they believe Trump’s actions are within his authority as commander-in-chief.
Congress approved $838.7 billion for the Department of Defense in January as part of its annual government funding process. Republicans approved another $150 billion for the Pentagon to spend on specific programs, like air and missile defense, as well as shipbuilding, in their “big, beautiful” law enacted in 2025.
But several GOP lawmakers said this week they expect the Trump administration will send a supplemental spending request to Capitol Hill in the coming weeks to bolster the military’s coffers.
White House press secretary Karoline Leavitt declined to say Wednesday if Trump will ask lawmakers for more funding for the Iran war, though she didn’t rule it out.
“I don’t have any updates for you on congressional asks from the president,” Leavitt said.
Any supplemental spending request would need to pass the House and move through the Senate’s 60-vote legislative filibuster to become law.
That would require support from at least seven Democrats in the upper chamber if all 53 GOP senators vote to advance an emergency spending bill for the war.
Pennsylvania Capital-Star is part of States Newsroom, a nonprofit news network supported by grants and a coalition of donors as a 501c(3) public charity. Pennsylvania Capital-Star maintains editorial independence. Contact Editor Tim Lambert for questions: info@penncapital-star.com.