Fast Facts

In fiscal year 2018, the Department of Defense incurred $46.5 billion in spending obligations for certain war-related activities overseas.

We found that these activities included:

Security forces training missions

In-theater base support operations (dining facilities, laundry, security, and housing)

Ship operations

Flying hours

Equipment maintenance and repair



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What GAO Found

In fiscal year 2018, Congress authorized $48.6 billion and appropriated $50.7 billion for operation and maintenance (O&M) overseas contingency operations (OCO), and the Department of Defense (DOD) reported obligating $46.5 billion. DOD reported obligating these funds for war-related activities, including security forces training missions, in-theater base support operations (dining facilities, laundry, security, and housing), ship operations, flying hours, equipment maintenance and repair, and transportation. The amounts reported as obligated in some sub-activity groups exceed the congressionally directed amounts for those same groups as a result of transfers and reprogrammings.

Why GAO Did This Study

According to DOD, since September 2001, Congress has appropriated approximately $1.8 trillion to DOD for OCO, primarily in Iraq and Afghanistan. The National Defense Authorization Act for Fiscal Year 2019 included a provision for GAO to report on how funds authorized to be appropriated for fiscal year 2018 for OCO were obligated. In fiscal year 2018, O&M OCO amounts comprised approximately 76 percent of DOD's OCO appropriations total of $66.8 billion. This report describes how amounts authorized and appropriated for O&M OCO activities were obligated by DOD for fiscal year 2018.

To determine how DOD obligated the amounts authorized and appropriated for O&M OCO activities in fiscal year 2018, GAO first compared authorized and appropriated O&M OCO amounts by sub-activity group. GAO then analyzed obligation data provided by DOD related to the same sub-activity groups.

For more information, contact Elizabeth A. Field at (202) 512-2775 or

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