A £9.4 million (US$16.2 million) UK National Lottery jackpot is going to good causes after the mystery winner failed to come forward by the deadline.
The 180-day limit for claiming the £9,476,995 Lotto prize expired at 5:30 last night.
It is the largest amount to go unclaimed since the National Lottery started over 11 years ago.
The ticket was bought in Doncaster, South Yorkshire, and Lottery organizers Camelot have made a concerted effort to alert people in the area about the missing winner.
Now, the money along with about £216,000 in interest, will go to the good causes fund.
A National Lottery official said: "To avoid this situation happening again, we would urge all National Lottery players to check their tickets on a regular basis.
"We have made numerous appeals to try to find the ticket-holder and it's a real shame that they have missed out, but there is still one winner — the nation.
"This money will now go to the good causes, adding to the £17 billion which, over the last 11 years, has funded the biggest program of civic regeneration seen in the UK since the 19th century."
The spokesman urged Lottery players who are concerned about losing tickets to consider playing on the Internet or by mobile phone.
The ticket was bought for the Lotto draw on July 6 and the winning numbers were 3, 12, 17, 36, 44 and 49.
Over the last 11 years there have now been 24 tickets worth over £1m that have gone unclaimed.