A NSW couple have unknowingly sat on a life‑changing lotto ticket for almost two months — only discovering this week they had won a $4.8 million Set For Life prize.

The Illawarra pair held the only division one entry nationally in the July 1 Set for Life draw, meaning they will now receive $20,000 a month for the next 20 years.

They discovered the win when they finally checked a ticket that had been sitting at home for seven weeks.

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“I’m all shaken up at the moment,” the woman told The Lott officials after finally claiming the win.

“I can’t believe it. I had no idea. This ticket has just been sitting on my desk at home the whole time.

“I kept saying ‘I’ve got to go check this ticket’ … and today we did.”

She said she’ had only been playing Set For Life for six months but always felt she would “win the big one”.

“It is literally a dream come true. We’ve been looking at retiring — we’ve worked hard all our lives but didn’t see it happening any time soon,” she said.

“This has changed our lives. You’ve no idea what this means to us. Things like this just don’t happen to people like us.

“This is seriously the best call I’ve ever had.”

The winning entry was purchased at Nextra newsagency in Kiama.