The Lotteries Commission says New Zealanders have a one in 3.8 million chance of winning the third biggest lottery prize ever this weekend.
The powerball jackpot of $25 million will be drawn at 8pm on Saturday night.
The commission is expecting ticket sales to double for the draw.
Lotteries Commission spokesperson Karen Jones says she would not encourage people to spend a lot of money on tickets, because the big draw could be won with the standard lucky dip.
And University of Auckland statistician David Scott says, while winning is purely down to luck, by choosing numbers higher than 31, punters can ensure they get a bigger share of the money as those numbers are less commonly used.
If powerball is not won this week it will reach the Lotteries Commission's cap of $30 million next week, meaning it will have to be won.