• A Mega Millions ticket purchased in North Carolina last December and worth $1 million is on the verge of expiring.
• Over the years, jackpots worth far more have also gone unclaimed.
• The length of time that winners get to claim their prize depends on the state where the ticket was purchased.

It looks like a Mega Millions player is about to join the ranks of lottery winners who end up missing out on a windfall.

A ticket purchased in Lewisville, North Carolina, and worth $1 million will expire Thursday at 5 p.m. The amount is a second-tier prize for matching five out of the six numbers that were pulled in the lottery game's Dec. 31 drawing.

"Sometimes people leave their tickets in a night stand, the glove compartment of their cars and trucks, or tucked away in a wallet," said Mark Michalko, executive director of the state's lottery.

"Check any Mega Millions tickets you have to see if you have the one from this drawing that won a $1 million prize," Michalko said.

Even some lottery jackpots go unclaimed

The current Mega Millions jackpot is an estimated $360 million for Friday night's drawing and Powerball's top prize for Wednesday night's pull is $365 million, making unclaimed lower-tier prizes pale in comparison.

Yet even some jackpot prizes have also gone unclaimed by their winners over the years in both national lotteries.

They range from a $16.5 million prize (one-third of a $50 million jackpot split three ways) from a ticket purchased in Florida in 2013 to a $77.1 million prize from a ticket purchased in Georgia in 2011. And several months ago in Maryland, a $10 million ticket won in Powerball's "Double Play" feature expired.

Beyond the top prizes or second-tier prizes, there are lesser amounts that also can end up unclaimed, whether due to loss of a ticket, forgetting to review the winning numbers or other mishaps.

On top of the multistate games, there are state-specific lotteries with prizes that never make it into the hands of winners.

For instance, in California in 2016, no one came forward with a winning ticket for a single lottery prize worth $63 million.

Unclaimed prize money goes back to the states

Each state that participates in Powerball and Mega Millions has its own rules for how long winners get to claim their prizes. Some allow three or six months, while others provide a full year from the date of the drawing.

So what happens to those unclaimed winnings? Generally speaking, the money goes back to the states selling the tickets.

And from there, it depends on the state's rules. In some places, the funds go back to players in the form of bonus prizes or second-chance contests. In other jurisdictions, the unclaimed amounts also may go toward specific purposes such as education funding.

The chance of winning the Mega Millions jackpot is 1 in about 302 million. For Powerball, it's 1 in 292 million. And for the expiring $1 million ticket, the winner's odds of matching the five white balls were 1 in 12.6 million.