She bought the ticket on October 27 on a weekend break in Carrick On Shannon in Co Leitrim.
The woman only found the ticket when tidying up at home after Christmas
And the new millionaire picked up her winnings at the National Lottery head office this week.
She revealed: “We were away for the weekend in Leitrim and for luck, I always buy a Lotto or EuroMillions ticket when I’m down the country.
“But I just completely forgot to check it! It was only when I was cleaning up after Christmas that I came across this ticket and I scanned it on the National Lottery phone app.