Pakistan said the MV Touska's 22 crew were flown in overnight and would be handed to Iranian authorities, while the vessel would be moved to Pakistani waters for repairs.
Islamabad described the release as a US confidence-building measure coordinated with both Washington and Tehran, and said it would keep supporting dialogue and mediation.
The Iranian-flagged ship was seized by the US Navy in the Arabian Sea on 19 April for allegedly trying to evade a blockade, amid wider US-Iran tensions around the Strait of Hormuz.
Can this diplomatic gesture succeed while the world's most vital oil chokepoint remains effectively closed by military force?
With a fragile truce ending, is this crew transfer a prelude to peace or a pause before war?