Someone out there has won $100m and might not even know it yet because they made one bad call.

A week on from the monster Powerball draw in which one ticket scooped the entire division one prize, and we are still none the wiser as to who is the lucky winner.

Have they lost the ticket, left it in the glovebox or down the back of the couch? Not sure.

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But the chance it could be lost is enough to send shivers down the spine of any dedicated lotto player.

And the mystery could have all been avoided by taking one simple step.

The Lott’s Khat McIntyre said the winner, who bought the ticket at a Bondi newsagency, could already be basking in their good fortune if they had registered it to The Lott Members Club.

“It’s the question many Aussies have been asking during the past seven days: who won last week’s $100 million Powerball prize, and do they know they’ve won?” she said.

“By registering your in-store or online lottery entry to The Lott Members Club, not only are we able to contact you straight after the draw if you win big, but your prize is secure.

“Even if you happen to lose or damage your winning ticket, if it is registered to you, we could still unite you with your prize, providing the ultimate peace of mind.”

Joining is free and could turn out to be a million-dollar decision.

Players in New South Wales have six years to claim their prizes. But surely they want to confirm their win as soon a possible?

“We pay division one prizes two weeks after the draw, so this prize is ready to be put into someone’s bank account in a week’s time – on Friday 27 June 2025. What a way to end the financial year!” Ms MacIntyre said.

“The first step is to give us a call on 131 868 if you think you are holding the division one winning entry.”