The new jackpot, the fourth-biggest ever, is up for grabs at the next drawing, which is set for Tuesday.
Friday's numbers were: 19-24-26-27-70, Mega Ball 12.
Lottery officials say they expect the amount to rise even higher before Tuesday's drawing, potentially reaching a billion dollars.
The largest Mega Millions jackpot ever claimed was $656 million in March 2012.
A change in the Mega Millions rules in October, which aimed at growing bigger jackpots faster, decreased the odds of a person winning the top prize to about 1 in 259,000,000.
Mega Millions is played in 43 states, the District of Columbia and the U.S. Virgin Islands.
