NASA says it’s on schedule to fly astronauts to the International Space Station on private spaceships beginning in 2017.
It will cost about $58 million a seat to get to low earth orbit.
Monday's briefing was NASA's first update on its Commercial Crew Program since a legal complaint about the bidding process was resolved earlier this month.
NASA Administrator Charlie Bolden says if the space agency is going to focus on Mars, it must rely on private companies to take astronauts to the space station.
"We made the conscious decision that if we're going to go to deep space we need to turn over things we are relatively sure that we know how to do, access to low Earth orbit, to American industry. And that's what we've done. You can see it. It's successful with cargo."
Boeing and SpaceX will launch astronauts from Florida. Astronauts have flown with Russia since the shuttle program ended in 2011.
Meanwhile NASA says Sierra Nevada remains a "valued partner." That company complained to the Government Accountability Office after failing to land a contract. The complaint was denied.
