He is also an art enthusiast and said he planned to invite six to eight artists from around the world to accompany him on his trip to the moon, drawing them from a global pool of painters, photographers, musicians, film directors, fashion designers, and architects.
Announced a year ago, the BFR ship will sit 118 metres long - previously announced as 106 metres (347 feet) long - and Musk has said the ship will contain up to 40 cabins which will have enough space for 100 people. "When you're pushing the frontier, it's not a sure thing", Musk said.
Boeing is working in parallel to get its CST-100 Starliner capsule ready for crewed flights to and from the space station.
A total of 24 NASA astronauts - all white men - voyaged to the Moon during the Apollo era of the 1960s and '70s.
"These artists will be asked to create something after they return to Earth", he said.
Neither Maezawa nor Musk would disclose the price of the flight, but Musk said that Maezawa - who had been one of the two customers for SpaceX's earlier plans for a circumlunar flight on a Dragon announced almost 18 months ago, but since shelved - had already made a down payment.
The Musk-led space company called the announcement "an important step toward enabling access for everyday people who dream of traveling to space".
Man City suffer surprise home loss to Lyon in Champions League
City were dominating possession ten minutes into the second stanza but they were yet to make risky attacks. If you don't win duels, play simple balls, you will suffer - today was another example of that".
Who will fly with the mystery passenger is among the many questions that Musk is likely to address during the announcement. "No one has visited since the last Apollo mission in 1972".
"Once operational Crew Dragon missions are underway for NASA, SpaceX will launch the private mission on a journey to circumnavigate the Moon and return to Earth".
In February 2017 SpaceX said two people had bought tickets to the moon for a flight that was supposed to take place this year. The vehicle also features three larger fins in the aft section, with landing legs integrated into them, and a pair of forward funs than can move.
According to Wired, SpaceX signed a lease in April close to its existing headquarters, where it will build the BFR. SpaceX did not reveal how much Maezawa paid, but just getting to low-Earth orbit costs a pretty penny.
SpaceX has had a string of successful rocket launches, but that has been overshadowed by the struggles of Musk's Tesla electric auto company to deliver and his behavior.
Shares in Tesla have had a turbulent time after the entrepreneur said in a tweet last month that he wanted to take the carmaker private.
Earlier on Monday it emerged Mr Musk was being sued for defamation over his repeated claims that a British cave diver was a child abuser.