The casino-owning Fertitta brothers always win — even when their investors lose.

Frank and Lorenzo Fertitta, who also own the Ultimate Fighting Championship cage-fighting franchise, are expected to hit a $1 billion-plus jackpot on their Las Vegas casino empire just a few years after causing it to go bankrupt.

When Red Rock Resorts sells shares to the public next week, the brothers will pocket most of the $500 million in initial public offering proceeds — and get the corporate jet — while keeping control of the company their father founded four decades ago, according to regulatory filings.

The Fertitta family, led by Frank and Lorenzo, will also retain a roughly 40 percent stake in Red Rock, worth close to $900 million.

The brothers said that in 2011 they doubled down on the business — which has grown to 21 casinos and resorts — after they won a bare-knuckled legal brawl to hold on to the bankrupt company.

“Lorenzo and I always believed in the business, and the family reinvested $250 million,” Frank told potential investors during a recent IPO roadshow.

That earlier restructuring effort also paid off handsomely for the brothers.

Red Rock, which used to be called Station Casinos, was publicly traded once before, in 2007, before the Fertittas and Colony Capital took it private for $9 billion.

The Fertittas got about $500 million for their shares and a 25 percent stake in the company, which was loaded up with debt just as the market was beginning to sour.

Two years later, it filed for bankruptcy, hobbled by $6 billion of debt.

After fighting creditors and a rival casino operator, the Fertittas emerged as winners again. They kept control of the family’s business while cutting $4 billion of debt from its books.

The brothers will reap another windfall with an IPO that’s expected to value Red Rock at $4.3 billion including debt — less than half what it was worth in 2007.

Most of the $496 million in net proceeds — assuming 27 million shares price at midpoint of the expected $18 to $21 range on Tuesday — will go to the Fertittas.

Red Rock plans to use $460 million to buy out Fertitta Entertainment, the brothers’ privately held management company.

The management company in 2011 signed a 25-year deal with the casino. The brothers will be paid out for the full contract in the IPO.

Red Rock is also paying off all the debt of the brothers’ company, including a $30 million loan for a 2011 Gulfstream jet that will be transferred to Fertitta Entertainment, filings show.

Critics of the deal — namely unions unhappy that Red Rock has kept out organized labor — point out that none of the IPO cash will go to pay down debt.

“It is alarming that potential investors in Red Rock’s second-class IPO are being asked to buy out an insider management company at a high, $460-million valuation, instead of paying down company debt or funding new growth initiatives,” said Ken Liu of Unite Here.