"Friday night's drawing produced a single winning ticket sold in New Jersey", the statement said.
The jackpot amount had climbed from United States $502 million to U.S. $521 million earlier in the day, but the final amount of the prize hadn't been announced late on Friday.
The amount is the fourth largest jackpot in Mega Millions' history, with the record set in 2012 at 656 million dollars.
The drawing on March 27 had two tickets, one in IL and another in New Jersey, match five of the drawing's winning numbers.
It's the 10th-largest lottery jackpot in the country.
The lucky numbers are 11, 28, 31, 46 and 59, with a mega ball number of 1.
Station manager Nash Riad said no one has come forward to say they bought the ticket, and he has no idea who the victor is. Three tickets - from California, Florida and Tennessee - shared that prize.
The jackpot now resets to its starting value of $40 million ($24 million cash) for the next drawing on Tuesday, April 3.
The lump sum for the Mega Millions is estimated at $301 million.