SpaceX, along with Boeing and the Sierra Nevada Corporation of Sparks, Nev., will receive over $1.1 billion for the project. Specifically, SpaceX will get a $440 million contract.
Once the spaceships are built, NASA plans to hire the private companies to taxi astronauts into space within five years.
This is the third phase of NASA's efforts to get private space companies to take over the job of the now-retired space shuttle.
The Associated Press contributed to this report.