The cost borne by the American government so far because of the war with Iran has reached $38 billion, the Congressional Budget Office (CBO) announced on Tuesday.
The estimate from the independent federal agency covers spending recorded from the start of military operations through last August.
Costs Set to Keep Rising
The CBO warned that even if the intensity of the armed conflict eases, the bill will keep growing by $2 billion a month. If the conflict escalates further, as it has in recent weeks, the cost will rise by $3 billion a month instead.
The total includes munitions and equipment used in combat, as well as fuel costs for US armed forces, which the CBO said are increasing. According to the agency's calculations, replacing the munitions expended since the war began on February 28 alone will cost $21.7 billion.
Interceptor Missile Stockpiles Depleted
The CBO also raised concerns about shrinking stockpiles of interceptor missiles. Comparing spending on these missiles with the total number purchased, the agency said the United States had probably used between half and two-thirds of its stockpiles since June 2025.
A Pentagon inspector general report released on Monday confirmed there were shortages of munitions linked to the war in Iran, a finding that the administration of President Donald Trump has repeatedly and categorically denied in recent months.
The CBO's analysis was carried out at the request of Democratic lawmakers. In July, Secretary of War Pete Hegseth had put the cost of the war at $37.5 billion. Pete Hegseth leads the US Department of War, the agency formerly known as the Department of Defense.
Inflation and Oil Supply Concerns
The CBO also estimated that the war in Iran will affect inflation in the United States, largely because of disruptions to the supply of oil and gas. Since the war began, Tehran has closed the Strait of Hormuz, a waterway of major strategic importance for the global trade in hydrocarbons.
Using the PCE price index, the budget office raised its inflation forecast for the first quarter of 2027 by 0.5 percentage points compared with its February projection. Its forecast for core inflation, which excludes volatile food and energy prices, was also revised upward, by 0.3 percentage points.
The CBO said the rise in inflation would also push up borrowing interest rates.
