The United States Armed Forces completed their withdrawal from Afghanistan on 30 August 2021, marking the end of the 2001–2021 war. In February 2020, the Trump administration and the Taliban signed the United States–Taliban deal in Doha, Qatar, which stipulated fighting restrictions for both the US and the Taliban, and in return for the Taliban's counter-terrorism commitments, provided for the withdrawal of all NATO forces from Afghanistan by 1 May 2021. Following the deal, the US dramatically reduced the number of air attacks on the Taliban to the detriment of the Afghan National Security Forces (ANSF), and its fight against the Taliban insurgency.

The Biden administration's final decision in April 2021 was to begin the withdrawal on 1 May 2021, but the final pull-out of all US troops was delayed until September 2021, triggering the start of the collapse of the ANSF. This collapse led to the Taliban takeover of Kabul on 15 August 2021.

As part of the United States–Taliban deal, the Trump administration agreed to an initial reduction of US forces from 13,000 to 8,600 troops by July 2020, followed by a complete withdrawal by 1 May 2021, if the Taliban kept its commitments. At the start of the Biden administration, there were 2,500 US soldiers remaining in Afghanistan and, in April 2021, Biden said the US would not begin withdrawing these soldiers before 1 May, but would complete the withdrawal symbolically by 11 September. The Taliban began a final offensive on 1 May and, on 8 July, Biden moved up the completion date to 31 August. There were about 650 US troops in Afghanistan in early August 2021, tasked with protecting Hamid Karzai International Airport and the US Embassy in Kabul. NATO's Resolute Support Mission concluded on 12 July 2021 while US intelligence assessments estimated as late as July that Kabul would fall within months or weeks following withdrawal of all American forces from Afghanistan, the security situation deteriorated rapidly.

The US also launched Operation Allies Refuge to airlift the American translators and select Afghan citizens considered at risk of reprisals and US Forces Afghanistan Forward was established on 7 July 2021 as a successor command overseeing the evacuation of all American diplomatic, security, advisory, and counter-terrorism personnel remaining in the country after the withdrawal of US troops.