A man in Auckland became a millionaire two months ago from a lucky Lotto ticket, but he didn't know it until he checked his ticket earlier this week.

The man, who wishes to remain anonymous, bought his ticket from an Ōtāhuhu dairy in time for the Lotto draw on September 18.

The million-dollar ticket was stashed safely in a drawer at the man's house for almost two months until he finally decided to check it.

"I was in bed around 10pm when I scanned the ticket on the Lotto NZ App and it came up with the words 'Major Prize'," said the man.

He and his wife leapt out of bed, not knowing yet how quite how "major" the winnings were.

When he checked his numbers on the MyLotto app, he was "in total shock" when he saw he had won $1 million.

"I can't believe we had no idea that we were sitting on a million dollar ticket this whole time!" he said.

The man usually plays his own Lotto numbers, but decided on a whim to draw random numbers in September. Despite not having chosen the numbers, the winning ticket still turned out to strangely personal.

"It was ironic because five of the six winning numbers were family birthdays. It was like I had picked them myself, it was perfect!" said the man.

Asked how he intended to spend his belated prize, he revealed his intention to continue life as normally as possible. But the unexpected fortune has given him and his wife more security and peace of mind as they head into retirement.

"We are also really looking forward to helping out our family and going on an overseas trip — it is nice to have that freedom," said the man.

The winning ticket was purchased from the Drury Lane Lotto Superette in Ōtāhuhu.