A £50.4 million jackpot – the result of 13 consecutive rollovers – went unclaimed on Wednesday, and new rules mean the biggest prize ever offered by the game must be won or shared out on Saturday.
The exceptional circumstances mean the odds of winning the jackpot are much improved at around one in 6.5 million compared to the usual one in 45 million.
The new rules, which come into play when a jackpot passes £50 million, dictate that if no players match all six numbers the prize will be shared between winners in the next tier where there is at least one winner – most likely those who have just five main numbers and the bonus ball.
The 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.
Operator Camelot said players will need to get their tickets before 7.30pm on Saturday.
It predicted it would sell 200 tickets a second in the hour before Wednesday’s draw, but the website struggled to cope with the enormous volume of traffic and the site was down for a “very brief period of about 10 minutes”.
Saturday’s prize eclipses the previous highest jackpot of £42 million shared by three winners in 1996.
The biggest cheque won on a single Lotto ticket was £22.5 million shared by work colleagues Mark Gardiner and Paul Maddison from Hastings in 1995, and the biggest ever individual Lotto winner is Iris Jeffrey from Belfast who won £20.1 million in 2004.
Camelot’s consumer and retail director Sally Cowdry said: “A life-changing sum of money has to be won. One way or another we will see massive or multiple millionaires made by Lotto.
“These are the draws players love, so don’t delay getting a ticket as it promises to be one of the most popular draws ever.”
Meanwhile, Dr John Haigh, emeritus reader in mathematics at the University of Sussex, said players would do well to think beyond lucky numbers, which tended to be birth dates, and ensure their selection extended across all numbers up to 59.
He said choosing six numbers entirely at random with a combined total adding up to at least 200, to make the average above 30, could not increase the chance of winning but could mean any prize money would be shared with fewer people.
But he warned that if everybody followed this advice, any advantage would be lessened.