A EuroMillions jackpot of €140 million is up for grabs tonight.
The National Lottery is advising people to play early ahead of this evening's draw.
If tonight's jackpot is not won, the jackpot will roll to €150 million on Friday.
If won in Ireland, tonight's jackpot would top Dolores McNamara's win of €115 million back in 2005.
National Lottery spokesperson Miriam Donohoe said: "She was the first ever Irish jackpot winner, and that scale of a win hasn't been repeated.
"This year, very early in January, we had a win of €38 million won by a small family syndicate in north County Dublin."