A record £66 million Lotto jackpot will be shared between two British winners, while a rollover in the US is expected to send next week's Powerball prize fund soaring to a staggering 1.3 billion dollars.
Each lucky UK winner will receive £33,035,323, scooping their share of the biggest ever jackpot.
However, just hours after Camelot revealed there were two winning tickets, officials for the US's version of the Lotto, the Powerball, announced their 949.8 million dollar (£654 million) jackpot had gone unclaimed.
It means the prize fund is expected to rocket to 1.3 billion dollars (£895 million) for next Wednesday's draw. By comparison, the next Lotto draw on Wednesday will be reset to £2.4 million.
The US jackpot was first set at 40 million dollars (£27 million) on November 4.
The Multi-State Lottery Association, which runs the Powerball, said it expected 75% of the possible combinations had been bought for the latest draw, although the odds of matching all six Powerball numbers are one in 292.2 million.
The UK's Lotto passed the £50 million cap on Wednesday and Saturday's £66 million fund, which had amassed after 14 rollovers, would have been shared among those tickets matching five main numbers and the bonus ball, had there been no winners this week.
Instead, those five ticket-holders each win £64,426.
The 259 tickets which matched five main numbers each win £1,309 while 17,695 matched four numbers to win £123.
There was a £25 prize for the 418,225 players who matched three numbers.
The main draw numbers were 58, 47, 27, 46, 52, 26 and the bonus number was 48.
A National Lottery spokesman said: "What an amazing way to start off the new year. Two players shared tonight's biggest-ever Lotto jackpot, and each ticket-holder will be starting 2016 £33 million richer.
"As well as the jackpot, as with every draw, the Lotto Millionaire Raffle created yet another guaranteed millionaire.
"We urge all our players to check their tickets and, of course, we have plenty of champagne on ice ready to welcome these winners into the National Lottery millionaires club."
The National Lottery website experienced some problems as an "unprecedented" number of last-minute buyers rushed to buy tickets.
Camelot said it expected to have sold at least 400 tickets per second, online and by retailers, in the final hours before sales stopped at 7.30pm on Saturday.
The recent run of rollovers follows the number of balls in the draw increasing from 49 to 59 in October, reducing the odds on a player's six numbers coming up from around one in 14 million to one in 45 million.
Saturday's top prize eclipsed the previous highest jackpot of £42 million which was shared by three winners in 1996.
Nobody won the Lotto Hotpicks jackpot which uses the same numbers as Lotto.
Thunderball's £500,000 top prize also went unclaimed after nobody matched five numbers and the Thunderball.
The numbers were 02, 03, 05, 22 and 11 and the Thunderball was 12.