Overview
- The Congressional Budget Office estimated in its Sept. 15 assessment that the Department of Defense has spent about $38 billion on operations in Iran through Aug. 1, 2026.
- CBO projects continued monthly DoD costs of roughly $2 billion to $3 billion depending on the intensity of fighting, with higher sums if operations escalate.
- Replacing expended munitions is the biggest cost at about $21.7 billion, and CBO says the U.S. has likely used between half and two‑thirds of key missile‑defense interceptors, which could take at least five years to rebuild.
- A Pentagon inspector general report through June 29–30 put obligations at $33.4 billion and documented dozens of aircraft and drones lost or damaged plus hundreds of damaged buildings and diplomatic facilities, and CBO says its estimate is uncertain because DoD did not provide requested data.
- CBO links the conflict to higher inflation — about a 0.5 percentage‑point lift to PCE inflation in early 2027 — and notes the White House’s June supplemental request of roughly $87.6 billion, with $42.3 billion tied to the fighting, remains unapproved, leaving households, military readiness and the defense industrial base at risk.