The winning €6.8million Lotto jackpot ticket from Saturday night was sold in the village of Mooncoin, Co Kilkenny.
Bosses confirmed the Quick Pick ticket was bought on the day of the draw in the Blanchfield Centra store.
Lotto chiefs also revealed that the lucky punter has already been in touch.
A spokesperson said: “We can confirm that we have been contacted by the ticketholder and arrangements are currently being made, when the winner is ready to collect their prize in the coming weeks."
The winning numbers from the draw were 13, 16, 18, 25, 38, 41 and the bonus number was 1.
And it was the second big win for the Centra in Mooncoin in the space of just a few months, after a €200,000 winning scratchard was bought there earlier this year.
Owner Michael Blanchfield said: “It’s astounding news. What a way to finish the year – selling a winning Lotto ticket!
"The news is the talk of the village and from talking to our local customers there is a great buzz about the place.
"I’ve no idea who it could be as we have a lot of regular locals but I do hope it is one of them. Whoever it is myself and all the staff at Centra wish them the best of luck with their win.
"We are in business here for 19 years and we had our first two major National Lottery wins in 2019.
"Back in March this year we sold an All Cash Spectacular scratch card that was worth €200,000 and was won by a Kilkenny couple."
