The Crown-owned entity is expecting to sell about 2 million tickets, and has put in extra measures to cope with high traffic on its online system.
Customers who buy their ticket in the last hour before sales close at 7.30pm may be placed in a virtual queue, as will those checking their tickets after the draw results are released at 9.15pm.
"To allow enough time for processing the extraordinarily high volume of tickets, the MyLotto site will also open later than usual the next day (Sunday), with Lotto NZ advising MyLotto will open at 10am on Sunday morning," Lotto NZ said in a statement.
And while the winning numbers will be released on Saturday night, the location and the store of the jackpot winner or winners will not be revealed until midday on Sunday.
"We would like to thank customers in advance for their patience as we manage what we expect to be exceptional interest in the results of this huge draw," Lucy Fullarton, Lotto NZ head of corporate communications, said.
"With so much excitement around the draw we want to ensure our players can enjoy the anticipation of the big win and have an opportunity to check their individual ticket before they hear in the news where the winning tickets were sold."
It has been four years since Lotto NZ has had a jackpot this high.
Wednesday night's $43m prize was not struck, and tonight's $50m draw will be the highest-equal jackpot in New Zealand's history. If no one wins the first division prize, it will be shared amongst those whose who win second division. If more than one ticket wins, the jackpot is shared.
With the prize money so high, more people tend to buy tickets to enter the draw - something Lotto NZ was aware of.
"We know that we've got a proportion of customers that buy tickets regularly, but actually, a much larger proportion only come into the draw at certain times, so when the jackpot gets to $20m, $30m or $40m.
"We do see at these levels a lot of people who would never normally buy a ticket, and don't even think about Lotto, they might see it in the news and think 'oh, I'll pick one up'."
