The United States has completed the withdrawal of its troops from Iraq, ending the military phase of a 12-year mission against the Islamic State group and transferring primary responsibility for Iraqi security to Baghdad.

U.S. Central Command said American and coalition forces had completed their departure from federal Iraq under a transition that accelerated after personnel and equipment left Erbil Air Base in September. The mission, Operation Inherent Resolve, began in 2014 after Islamic State captured large areas of Iraq and Syria.

In a statement, CENTCOM commander Admiral Brad Cooper described the withdrawal as the conclusion of a campaign that had defeated Islamic State as an organised military threat in Iraq and the region. He said the shift marked a move toward an Iraqi-led security effort supported by a more normal bilateral relationship, including targeted training and intelligence support.

The withdrawal followed a 2024 agreement between Baghdad and Washington. It has been welcomed by Iran-aligned groups that had long called for U.S. troops to leave, but it has also raised concern among some Iraqi and Kurdish officials about Islamic State sleeper cells and the possibility of greater pressure from armed factions outside state control.

AP reported that the last U.S. troops left a northern Iraqi air base by the 30 September deadline. Iraqi authorities presented the completion of the mission as a marker of sovereignty, while the U.S. administration described it as an orderly conclusion to a long and costly deployment.

The withdrawal should not be read as the end of all U.S.-Iraq security contact, nor as proof that the threat from Islamic State has disappeared. It is the end of a particular coalition military mission. The questions now concern how Baghdad manages the armed groups operating within its borders and how the new security relationship works in practice.