A Brisbane grandfather has become an overnight multi-millionaire after winning the entire Powerball jackpot.

The Wynnum man has had an ectatic start to his weekend after he was informed on Friday that he had scored an eye watering $31,140,405.47.

The man was left in disbelief after being told he held the only division one winning entry.

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“Holy sh**! Wow. Unbelievable!” he said.

“Oh, my goodness. Words can’t explain how I’m feeling right now. Dear, dear, dear.”

After discovering the scope of his winnings, the man said the sum will do “so much” for his family.

“It’ll set up my kids and grandkids,” he said.

“Never in a million years did I think I would get this call.

“I’m retired myself. I’ve lived a happy life, and I’ve been lucky enough to tick most things off my bucket list, so this will be used more for helping others.”

Speaking to The Lott over the phone, the man said he just “couldn’t believe it” and that the most he had ever won was a chocolate Easter basket.

“These are my numbers I’ve played for years,” he said.

“I chose them a long time ago now. I usually play Saturday Gold Lotto, but sometimes I play Powerball when it has a higher jackpot.

“It’s funny because I also bought a Set for Life ticket and thought, ‘Wow, it’d be nice to get that’, but this is even better!

“You’ve made my day. You’ve made my week. You’ve made my kids’ lifetime!

“Now, I’m going to have a quiet day, letting reality set in.”

His winning marked PowerHit entry was purchased online on the Lott website.