The US says is is spending more than $9 million a day on its war against the Islamic State group.
The defence department said more than $2.7 billion had been spent by US forces since a coalition was formed to tackle the IS group last August.
The US air force spent two-thirds of the money, or more than $1.8 billion. Combat, reconnaissance and other flights cost more than $5 million a day. Special operations costs, which are rarely revealed, totaled more than $200 million.
The defence department said more than $2.7 billion had been spent by US forces since a coalition was formed to tackle the IS group last August.
The US air force spent two-thirds of the money, or more than $1.8 billion. Combat, reconnaissance and other flights cost more than $5 million a day. Special operations costs, which are rarely revealed, totaled more than $200 million.
Other costs included $438 million for the navy, and $274 million for the army.
US planes have been striking IS targets in Syria and Iraq on a daily basis. The US military is also training Iraqi forces and Peshmerga fighters.
The release comes after Congress rejected legislation that would ban further spending on the military operation against IS until politicians passed a new war powers resolution.
IS began a rapid expansion in Iraq and Syria last June, and captured Mosul, Iraq's second largest city, days later.
IS captured the ancient Syrian city of Palmyra and Ramadi last month, dealing a further blow to anti-IS forces.
The Iraq war, launched by George W Bush in 2003, cost the US $720m a day, according to the Washington Post.