The single ticket matched all six numbers drawn to win the jackpot worth $1.326 billion, Powerball said in a statement.
And they're being allowed to keep their winnings.
The jackpot for the next drawing Wednesday night will be among the largest lottery prizes of all time.
Officials say there have been 11 winning jackpots of $500 million or more since Mega Millions began in 2002.
The Powerball prize keeps getting more massive because of the inability of anyone to overcome the long odds of 1 in 292.2 million and win the jackpot.
No one matched all six numbers and won the estimated $825 million grand prize on Saturday.
Striking it rich can draw scammers, scads of sad stories and trigger personal struggles.
Michael Todd Hill was convicted of first-degree murder in the slaying of his girlfriend.
Organizers blamed "human error" for the multistate lottery's mixup.