The winning numbers were 2, 15, 19, 26, 37, 38 and bonus number 39
Last night's winning Lotto ticket was sold at SuperValu in Knocklyon, Dublin 16.
The jackpot was worth €12.8 million - the largest jackpot of 2017 so far.
The winning ticket was a Quick Pick, while the numbers drawn were 2, 15, 19, 26, 37, 38 and the bonus number 39.
The National Lottery is urging the winner to sign the back of the ticket, and contact their prize claims team on 01-836-4444.
Another winner will take home a prize of €179,034 after matching five numbers with the bonus in last night's draw.
That ticket was sold in SuperValu on the Abbeyleix Road in Portlaoise.