The prize fund, built up following a marathon 14 rollovers, must be won today - and this has led to an "unprecedented" level of interest, with an estimated 400 tickets being sold every second before sales closed.
Saturday's Lotto results were as follows: 26, 27, 46, 47, 52 and 58. The bonus ball was 48.
If nobody manages to match all six numbers, the £57.8m haul will be shared between ticketholders who have five numbers, in addition to the bonus ball.
The National Lottery had earlier emailed online players to warn of the "high volumes of visitors" expected to its website - and had urged Britons to consider purchasing a ticket from newsagents and high street retailers instead.
According to Camelot, this was one of the highest-selling draws in the Lotto's history - meaning more cash can be given to charitable causes.
A spokesman has apologised to anyone affected by the technical difficulties on the National Lottery website, which also struggled to cope before Wednesday's unclaimed £50.4m jackpot.
The inflated jackpot comes after lottery operator Camelot made controversial changes which experts said would make it three times harder to scoop the top prize.
The number of balls was increased from 49 to 59, which mathematicians calculated reduced the odds of a player getting all six numbers from about one in 14 million to one in 45 million.
However, Camelot has argued the changes have increased the chances of becoming a millionaire.
A single winner would net a fortune to rival that of Kylie Minogue, who has £55m in the bank, and dwarf Ed Sheeran's paltry £20m.
The previous jackpot record was £42m, which was shared between three ticket-holders in January 1996.
The biggest UK Lotto win was in 1995 when colleagues Mark Gardiner and Paul Maddison shared £22.5m, although Mr Gardiner later revealed the money did not bring him happiness.
The biggest single winner was Iris Jeffrey from Belfast, who scooped £20.1m in 2004.
Meanwhile, in the US, the Powerball lottery - which is also being drawn on Saturday night - has climbed to a record $900m (£620m).
One of those to enter the jackpot draw is Ruth Breen from Wigan, who won £1m on EuroMillions in 2014.
Despite her win she continued to work but reduced her hours. She invested half her winnings and also paid off her mortgage.
Buying two lucky dip tickets for the Saturday lottery, she told Sky News: "I have got a good a chance as anyone else."
Lotto rules mean the jackpot has to be won in the first draw after it reaches £50m.