If you play EuroMillions it's going to cost you more from Saturday September 24, with the cost of a line rising from £2 to £2.50.
Under the changes players will also have to choose an extra number, which will lengthen the odds of winning the jackpot from one in 117 million to one in 140 million.
However, Camelot says the changes will mean bigger prizes and double the number of UK millionaires.
Why the changes?
Camelot, one of the 10 operators of the European-wide game, say the changes are needed to "reflect all of the community-wide and UK-only enhancements".
Community-wide benefits will include bigger jackpots more often, with higher starting jackpots of £14 million and more than twice as many jackpots over £50 million a year, it adds.
There will also be bigger promotional draws offering jackpots from £100 million and a new ‘must-be-won’ European Millionaire Maker events, from the end of October, which will create 25 extra millionaires.
In addition to these community-wide changes there will also be UK-specific enhancements too.
There will be at least two UK millionaires in every draw through the UK Millionaire Maker, which means at least 208 a year will become millionaires in the UK – double the current number.
There will also be a Mega Weeks event at the end of every month, which will mean more UK players winning guaranteed £1 million prizes and luxury lifestyle experiences. These will take place on Tuesdays and Fridays.
To make the changes possible the number of Lucky Stars players can pick from will expand from 11 to 12 and the cost per line will rise 50p to £2.50.
How to play
Players will still have to select five number from one to 50, but the two lucky stars will have to be picked from one to 12 rather than 11.
EuroMillions is played in nine countries including Austria, Belgium, France, Ireland, Luxembourg, Portugal, Spain, Switzerland and the UK.
The odds of winning the jackpot in the Euromillions is currently 1 in 116,531,800 and the overall odds of winning a prize is 1 in 13.
When the changes come into force the odds of winning the jack pot will lengthen to one in 140 million but the overall odds of winning a prize will remain the same.
Tickets for the first new Euromillions draw on September 27 go on sale today.