Expedition 63 was the 63rd long duration mission to the International Space Station, which began on 17 April 2020 with the undocking of the Soyuz MS-15 spacecraft and continued until the undocking of the Soyuz MS-16 spacecraft on 21 October 2020, an unusual double-length expedition increment. The Expedition initially consisted of American commander Chris Cassidy, as well as Russian flight engineers Anatoli Ivanishin and Ivan Vagner. On 31 May 2020, the Expedition welcomed the crew of Crew Dragon Demo-2, the first crewed flight of SpaceX's Crew Dragon spacecraft, named Endeavour after the eponymous Space Shuttle vehicle. The mission's two crew members Doug Hurley and Bob Behnken undocked from the International Space Station on 1 August 2020 to help bolster research on the station and participate in several spacewalks outside of the station.

Soyuz MS-16 was a Soyuz spaceflight launched on 9 April 2020, which transported three members of the Expedition 62/63 crew to the International Space Station.