The quarterly results, which include one-time transaction and other related costs, come as the company is aiming for a first commercial flight later this year with Branson on board.
"It will be a transformative moment for the company," Chief Executive George Whitesides told analysts on a conference call, adding that revenue and cash flow will ramp up in 2021.
Shares of Virgin Galactic were volatile in after-hours trading and were last down 6.4%. Shares had rallied in recent days, driven by investor interest in the first space tourism company to hit public markets.
Virgin Galactic competes with billionaire-backed ventures such as Blue Origin, founded by Amazon.com Inc CEO Jeff Bezos, to be the first to offer suborbital flights to fare-paying thrill seekers, presaging a new era of civilian space travel that could kick off as soon as this year.
Other players including Elon Musk's SpaceX and Boeing Co have their sights set on higher altitudes like the International Space Station, the moon and eventually Mars.
Some 600 people from 60 countries have paid or put down deposits to fly on one of Virgin's suborbital flights, worth about $80 million in total collected deposits and $120 million of potential revenue, the company said.
A 90-minute flight, which allows passengers to experience a few minutes of weightlessness, costs about $250,000.
Now, Virgin plans to seize on a wave of more than 7,900 "registrations of interest" it has received since then from would-be astronauts by collecting $1,000 deposits to secure a place in line as seats become available, it said on Tuesday.
Virgin Galactic has invested $1 billion in its reusable mid-air launch technology and said on Tuesday it was in talks with Italy and United Arab Emirates for potential spaceports.
Closer to Earth, Virgin also plans to develop hypersonic passenger air travel that could dramatically cut travel times across the world, the company said. For example, flying from New York to London would take about an hour, it said.
The company, which went public last year, reported fourth-quarter revenue of $529,000, and $3.8 million for 2019, the first full year of results.
(Reporting by Eric M. Johnson in Seattle; Editing by Tracy Rucinski and Matthew Lewis)
By Eric M. Johnson