US missions in Turkey are to resume full visa services following security assurances from Turkey’s government on US consular staff.
The US had suspended all non-immigrant visa services after the arrest of one of its consulate employees in October.
The worker had been detained over suspected links to a cleric blamed for last year’s failed coup in Turkey.
The state department said it was “confident that the security posture has improved sufficiently”.
Turkey had “adhered to high level assurances” made to the US, it said.
The statement said the US had been assured no additional local employees of its missions were under investigation and that staff would not be detained or arrested performing their official duties.
However, the state department also said it still had serious concerns about allegations against its arrested local employees and about cases against US citizens who have been detained under the state of emergency.
There are at least 11 US citizens currently under arrest in Turkey.
The Turkish embassy in Washington welcomed the US decision and said visa restrictions for US citizens imposed during the dispute would also be lifted.
However, it said Turkey had given no assurances to the US about cases being processed by Turkish courts, and that it also had ongoing concerns about Turkish nationals undergoing court cases in the US.
Washington had condemned the arrest of the consulate employee, a male Turkish citizen, as baseless and damaging to bilateral relations.
Turkey has for months been pressing Washington to extradite US-based cleric Fethullah Gulen over his alleged role in the botched coup in July 2016.
Turkish President Recep Tayyip Erdogan accuses Mr Gulen of instigating the unrest – a charge the cleric denies.
In the aftermath of the coup attempt, which was led by military officers, 40,000 people were arrested and 120,000 sacked or suspended.