Winning enough money to never have to work again might be reason enough to shell out a few dollars for lottery tickets — and the Powerball and Mega Millions jackpots are currently worth nearly $1 billion combined.

But horror stories of lottery winners who mismanaged their jackpots and ended up losing it all abound. You might rightly wonder: How large of a jackpot would actually be enough to support you for the rest of your life?

Nearly $5 million, according to Robert Pagliarini, president of Pacifica Wealth Advisors.

Pagliarini is a certified financial planner who specializes in advising lottery winners on how to manage their sudden wealth. Looking at the current lottery jackpots, with Mega Millions at $454 million and Powerball at $494 million, he says anyone who wins either of those prizes will be set for life — if they manage that money wisely.

But that's a big if. Here's why.

How big of a jackpot do you need to quit your job and retire early?

Managing lottery winnings smartly is easier said than done. Pagliarini acknowledges that "there are so many variables" to consider when it comes to how much money each person would need to support themselves, and possibly their family, forever.

"It depends on someone's age, it depends on where they live, what their tax situation is like, how much they've already saved, if they're getting Social Security," he says. "There's limitless numbers of variables."

To quit your job and retire immediately on lottery winnings, "you basically want to replace 100% of your income," Pagliarini says. That means winning an amount of money that, when properly invested in a low-risk investment portfolio, will yield enough returns for annual withdrawals at least equal to your current annual salary — without exceeding 4% of your winnings, a common financial planners' rule.

Say you win a $4.47 million lottery jackpot, and opt to take lump sum payout — typically about 66% of the total advertised jackpot, Pagliarini notes — over the annuity option, which splits a larger total amount into annual installments paid out over 29 years.

Your payout would be roughly $2.9 million, resulting in a take-home amount around $1.77 million after accounting for roughly 40% in federal and state tax bills, depending on where you live.

If you stash that money in a low-risk investment portfolio, you could then safely withdraw 4% of it annually, which would be $70,800. That's just above the country's median household income: $70,784, according to the U.S. Census Bureau.

Pagliarini's rule of thumb is to multiply your current salary by anywhere from 70 to 100 to get a good idea of what you'd need to survive on at your current spending rate over the next several decades. 

"I like 100 times their salary a little bit better, because it gives them a cushion," he says.

Using that formula, a person making $100,000 a year would need to hit a lottery jackpot of $10 million to continue their current lifestyle, while allowing some responsible splurges — buying a new house or car, paying off any outstanding debts or sharing some of the winnings with friends and family.

Using the same math, the winner of the current Powerball or Mega Millions lottery could allocate roughly $5.5 million of their prize annually to spend as they see fit.

"I don't know about you, but I could probably squeeze by on [that]," Pagliarini says.

Correction: This story has been updated to reflect that a roughly $5 million lottery jackpot could replace a median American salary, according to Pagliarini.

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