FILE PHOTO: Signs advertising the sale of the winning Mega Millions ticket outside the KC Mart in Simpsonville, South Carolina, U.S. October 24, 2018. REUTERS/Charles Mostoller/File Photo

(Reuters) - A $321 million Mega Millions jackpot, the biggest ever offered on Christmas Day, went unclaimed as the size of the grand prize grew for the next drawing later this week, the multistate lottery said on Wednesday.

No one held the numbers 2, 8, 42, 43, 50 and Mega ball 6 that were picked Christmas night, Mega Millions said. The jackpot increased to $348 million for the next drawing to be held on Friday.

It was the fifth time a Mega Millions drawing was held on Christmas Day, and each one has failed to produce a jackpot winner.

Mega Millions tickets are sold in convenience stories, news stands, grocery stores and other retail outlets in 44 U.S. states, the District of Columbia and the Virgin Islands.

The value of the jackpot is calculated on the basis of a 29-year payout, but winners can opt for a lump sum payment instead, which would be $210.2 million for Friday’s drawing, Mega Millions said.

Powerball, the other multistate lottery, will hold one of its twice-weekly drawings on Wednesday night with a $294 million jackpot and an instant cash value of $177.6 million.

While the odds of hitting the Mega Millions jackpot are one in 302.6 million, the chances of turning a $2 ticket into a winner of any kind, including a $2 prize simply for matching the “Mega ball,” are one in 24.

The biggest-ever Mega Millions prize of $1.537 billion went to the holder of a single ticket in a drawing on Oct. 23. The ticket was sold in South Carolina but the winner has yet to come forward, Mega Millions said.

That winning ticket fell just short of the U.S. record, a $1.586 billion Powerball grand prize in 2016.