Lotto changes coming in this Saturday (October 10) will mean that players are less likely to win the jackpot.
Under the new rules, the pool of numbers for players to choose from will increase from 49 to 59. At the moment, players choose six numbers up to 49, with odds of winning the jackpot sitting at just under one in 14 million.
These will lengthen to around one in 45 million from Saturday, according to mathematicians.
Camelot says the idea is to create "bigger rolling jackpots" where there is "more to play for".
It's the biggest shake-up since the National Lottery started 21 years ago.
A new Millionaire’s Raffle will also be introduced as part of the changes.
The new draw will guarantee at least two millionaires every week in addition to 20 winners of £20,000 every time.
Players who match two numbers will win a Lucky Dip for a future draw too. Camelot says that this will create 1.8 million winners each week, increasing the chance of winning any prize from one in 54 to one in 9.3.
The cost of playing will still be £2 a line. Other prizes, like £25 for matching three numbers, will also remain the same.
If you want to keep the same lines you've always played you canor you can swap in a few higher numbers.
There's an estimated jackpot of £4.5 million up for grabs in Saturday's draw.