Most read: Are you holding the winning $7.2m Powerball ticket bought in Auckland?

This story was first published on Monday September 17.

Lotto is on the lookout for a $7.2 million Powerball winner who still hasn't claimed their prize five days after last Wednesday's draw when a ticket bought in the north Auckland suburb of Silverdale struck the jackpot.

The winning ticket was bought at Pak'nSave Silverdale and Lotto is urging anyone who bought their ticket from that supermarket recently to check their tickets.

While the majority of Powerball winners are quick to claim their winnings, it's possible that New Zealand's latest multi-millionaire has no idea they've hit the jackpot, said Kirsten Robinson, Head of Corporate Communications at Lotto NZ.

"That's why we're encouraging anyone who bought their ticket from Pak'nSave Silverdale recently to do a bit of spring cleaning - clear those wallets, clean out your kitchen drawers and rummage through the glovebox. You never know, that little yellow piece of paper tucked away somewhere special, could be worth $7.2 million," she said.

The winner has 12 months from the date of the draw to claim their prize.

While most winning Lotto tickets are found tucked in wallets, they've also been known to show up in weird and wonderful places - including underwear drawers, backpacks, in the desk at work, hidden in the car, and even tucked inside phone cases, Ms Robinson said.

Last year a Warkworth man discovered he was $19.1 million better off after checking a Powerball ticket he had stashed in his car.

In April 2013, a Christchurch man found a Lotto ticket worth $666,666 in his "odds and ends" drawer.

Anyone who bought their Powerball ticket from Pak'nSave Silverdale for the 12 September 2018 Lotto draw should write their name on the back of the ticket and check it immediately at any Lotto outlet, online at mylotto.co.nz or through the Lotto NZ ticket-checker app.

Big winners can also call the Lotto New Zealand helpdesk on 0800 695 6886 for information on how to claim their prize.