The Christchurch winner, a sparkie in his late 50s, had the winning ticket in his wallet the whole time but had resisted the urge to check his ticket straight away, Lotto said in a statement.
"It's been all that anyone has been talking about around here," said the winner.
"Like everyone else in Christchurch, friends have been asking me if I had a Lotto ticket – and then asking me why I hadn't checked it yet."
The man knew he had bought his ticket from the Hornby Mall Lotto, where the winning ticket was bought. He decided to delay checking his ticket so he could keep pretending he might be the winner for a bit longer.
"I thought when I checked my ticket, I'd find out for sure it wasn't me. And it was fun to dream for a while," he said.
He checked the ticket midweek, but had a knot in his stomach when he handed it over, he said.
Then the winning music rang out and the words "First Division winner" popped up on the screen. "The Lotto lady handed me a piece of paper that said '$20.2 million' on it.
"You think you know how you're going to react when you get news like that, but to be honest all I felt was this huge sense of relief. My first thought was 'yay, I can retire now'."
The winner headed straight to his partner's work and handed her the paperwork. "All she said was 'you've got to be kidding me, right?'
"There a few tears and a couple hugs, but we had to hold it together as she had to go back to work. I don't think she got much done that day."
The pair sat down with a drink in hand and started calling their immediate family, many of whom shed happy tears for the pair.
The winner said what made it more special was that they had already given away half the money.
"Family is the most important thing and we are so excited to be able to share our luck with the people we love most – and know that it's not just our life that has changed.
"And by giving half away, there's no chance I'll go crazy with my winnings ... It'll keep me on an even keel."
He also plans to use some of the winnings to take their families on holiday next year.
