NASA's Terry Virts, Samantha Cristoforetti of the European Space Agency and Russia's Anton Shkaplerov returned to Earth after 199 days on the station, nearly a month more than planned.
Their Soyuz capsule landed on schedule Thursday about 145 kilometers (90 miles) southeast of Dzhezkazgan.
The mission's extension was caused by the failed launch of a Russian cargo ship in April.
VIDEO: Astronaut recites 'Twinkle Twinkle Little Star' while aboard ISS
The Soyuz rocket that failed in April is used to launch spacecraft carrying crews, so Russian space officials delayed the crew's return and further launches pending an investigation.
A Soyuz rocket successfully launched a satellite last week, and a new crew is set to head to the station in July.
It took me until my last day in space to get a good picture of these! pic.twitter.com/BChtFZBvk7— Terry W. Virts (@AstroTerry) June 10, 2015
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