Standard UK Lotto draws Wednesday and Saturday at 19:45 GMT. Each line picks 6 main numbers from 1 to 59 plus a Bonus Ball drawn afterwards. Match-6 (all 6 mains) is approximately 1 in 45.06 million per line. The starting jackpot is a Standard £2 million on a fresh post-payout week, climbing through rollovers.
The 5-roll cap: introduced by Camelot in 2018 and retained by Allwyn after the 2024 license transfer. After a Match-6 win, the next jackpot resets to £2M. Every week without a Match-6 winner, the jackpot rolls forward (typically £2M-£5M added per roll, depending on ticket sales). After five consecutive rolls without a Match-6 winner, the next draw is flagged Must-Be-Won.
What 'Must-Be-Won' means in practice: the jackpot pool — which by the fifth-roll point is typically £20M-£30M — must be paid out. If somebody matches all 6, they take the lot. If nobody matches all 6, the prize slides down to Match-5+Bonus winners, then Match-5, etc., until a tier with at least one winner absorbs the entire jackpot pool. This is called a Boosted Payout draw.
Practical effect on Match-5+Bonus and Match-5 winners: in a normal week, Match-5+Bonus pays around £50,000-£100,000 per winner. On a Boosted Payout (when nobody hits Match-6), Match-5+Bonus winners can split £15M-£25M among them — usually a handful of tickets each landing in the £1M-£5M range.
Comparison with NZ Lotto Must-Be-Won: NZ Lotto's First Division must be paid when it hits NZ$1M and rolls 4 weeks; UK Lotto's mechanic is similar in spirit but triggers at the 5-roll mark and from a much higher base jackpot. Both give the same dramatic effect: a forced payout where the lower tiers absorb the prize money if nobody matches the headline.
Spotting one before draw night: Allwyn marks Must-Be-Won draws prominently on lottery.co.uk and on retailer terminals starting the Saturday before. Check the official site or any of our /uk/lotto/[date] result pages from the previous five weekends — if Match-6 winners == 0 across all five, the next draw is Must-Be-Won.