Lottery players will have their fingers crossed as they buy their tickets for the first ever quadruple rollover.
No-one scooped Wednesday night's jackpot so Saturday's top prize will be a bumper £19.3m.
A National Lottery spokeswoman said: "This is the first ever quadruple rollover and a massive milestone for The National Lottery and its millions of players across the UK. Everyone will be crossing their fingers and planning what they would do if they land the bumper jackpot prize which must be won on Saturday."
She continued: "Whatever happens, whenever there is a big jackpot like this, the whole nation comes out as a winner - as more people playing means more money raised for the National Lottery Good Causes."
The winning numbers for Wednesday's draw were 40, 8, 6, 39, 43 and 11, and the bonus number was 22, Camelot said.
Set of balls six and draw machine Lancelot were used.
Four ticketholders matched five numbers plus the bonus to take home £250,484, while 357 won £1,754 for five numbers.
A total of 18,486 matched four numbers to claim £74 each, while 360,655 won £10 for matching three numbers.
Nobody won the top prize of £130,000 in the Lotto HotPicks draw.
In the Thunderball draw, the winning numbers were 2, 14, 21, 3 and 37, and the Thunderball number was 9. No one won the £500,000 top prize.