One lucky Lotto player is $20.2 million richer after coming forward to claim Saturday's big prize.
A Lotto spokeswoman says "someone has come forward who we believe to be the winner".
"It's exciting," she says.
Lotto would be going through its processes to confirm this person is the winner.
There was no further information at this stage, she says.
The winning ticket was sold at Hornby Mall in Christchurch, with the prize made up of $20 million from Powerball First Division and $200,000 from Lotto First Division.
The winning numbers were 2, 11, 15, 29, 30, 38, with a Powerball of 7 and the bonus ball 36.
Saturday's Powerball win is the first for 2018 and the fourth largest prize ever won in the South Island and the 12th largest win nationwide.
The store has sold 30 First Division tickets making it the fourth 'luckiest' store in New Zealand.
In addition to the Powerball winner, there were four other first division winners who won $200,000 each.
The other winning Lotto tickets were sold at Molesworth Four Square in Mangawhai, Botany Junction Four Square in Auckland, Richmond Night n Day in Nelson and on MyLotto to a player from Auckland.