"I went into the supermarket to buy our usual Saturday ticket and checked the Wednesday ticket at the same time," one of the winners said.
"When the machine flashed that the ticket was a First Division winner, I looked around to see if anyone had noticed and when I realised they hadn't, I snuck out of the store."
He went back to his car and shared the news with his wife, who went to check again at another self-scanner at a gas station to be doubly sure.
"When she got back into the car we just started laughing. Then we just sat there for a minute taking it all in, still not knowing how much we had actually won," the man said.
It wasn't until the winners dropped by a friend's house that they found out how much they had won.
"Our friend asked if we'd heard about the lucky people who had won $7.5 million from a Lotto ticket bought in Lower Hutt," he said, laughing.
"My heart started racing and a few expletives came out."
The couple returned to Pak'nSave, where they had bought their ticket, to claim their prize.
"The look on the retailer's face was priceless when the bells and whistles went off," the husband said, "and when he showed us what we had actually won, it was such a surreal moment. It's still pretty unbelievable."