The bill for the US conflict with Iran has passed $38 billion, according to a new assessment from the Congressional Budget Office, and the meter is still running at up to $3 billion a month depending on how intense the fighting gets.

The nonpartisan CBO released the figures on Tuesday in response to a request from Rep. Brendan Boyle, the top Democrat on the House Budget Committee. The tally covers Department of Defense spending through August 1 and mostly reflects the cost of replacing munitions and equipment destroyed in battle. Notably, it excludes the human costs — nothing for troops killed or injured, and nothing for long-term veterans' healthcare or disability payments.

The numbers broadly match what Defense Secretary Pete Hegseth told the Senate: $37.5 billion. The war began February 28 and is now in its seventh month, with no clear end in sight. The White House asked Congress for $87.6 billion in supplemental funding back in June, much of it for the war effort, but that request hasn't been approved. The CBO estimates the conflict-related slice of it, $42.3 billion, would actually run about 10% above its own cost projection.

There's a knock-on effect for household budgets too. The CBO expects the war to push inflation roughly half a percentage point higher than previously forecast through the first quarter of 2027, mainly because oil and gas shipments through the Strait of Hormuz have been reduced and Red Sea shipping has been disrupted. For anyone booking flights or holidays, that's the kind of pressure that shows up in fuel surcharges and airfares over time.

The political stakes are rising alongside the costs. With midterms approaching that will decide control of Congress, voters are weighing both the war and persistent high prices. Boyle criticized the spending, arguing that lawmakers who say the US can't afford domestic programs have found tens of billions for a conflict that's ultimately costing taxpayers.

The report wasn't straightforward to produce. The Pentagon broke with normal practice and declined to answer the CBO's questions, so the budget office had to work from government databases and public reporting — and it flagged its own figures as carrying considerable uncertainty. Meanwhile, a Pentagon inspector general report released Monday found the war has created strategic inventory shortfalls, meaning US weapons stockpiles are being drawn down faster than they're being replaced.

Why does this matter to travellers? Beyond the direct human toll, a prolonged conflict in the Gulf region keeps energy prices elevated, disrupts shipping and airspace, and feeds into broader inflation — all of which eventually touch the cost of getting anywhere. Anyone with trips planned through the Middle East, or connections routing near the Strait of Hormuz or Red Sea corridors, should keep an eye on how this conflict develops.

First reported by Japan Today.