The "Painted Ladies," a row of historical Victorian homes, are shown with the San Francisco skyline in the background.

California could reap a bonanza of "$1 billion or more" in new taxes from the upcoming stock offering of ride-hailing service Lyft, according to state's former treasurer.

Experts say Lyft's initial public offering and an even bigger IPO expected in April from rival Uber will create many newly-minted millionaires in the Bay region. The state stands to benefit by taxing the capital gains from stock sales.

"We need those billions for education and other areas," said John Chiang, the state's former treasurer and controller. He said new tax collections "may not happen all at once, and could be spread over time."

According to its regulatory filing Monday, Lyft is gearing up for an IPO that values the company at near $20 billion. Lyft itself proposes to raise more than $2 billion in proceeds from the offering.

"If you're coming with a $19 billion valuation, you're talking about [a state income tax rate of] 13.3 percent for the millionaires," Chiang told CNBC. "Even though we're looking at all-in state budget in excess of $200 billion and a general fund budget of about $140 billion-plus, $1 billion or more is significant."

Lyft's two founders stand to get a big payday from the IPO and keep control of just under half of the company's Class B voting stock. CEO Logan Green's stake could be worth more than $540 million and the company's president John Zimmer's, valued just under $400 million.

For Californians, the state taxes capital gains like any other income. As of 2017, about 70 percent of the the state's general fund revenues come from personal income tax collections.

"IPOs are good for California's bottom line," said Chris Thornberg, a founding partner with Beacon Economics. The economist said a larger share of the state's general fund today comes from personal income taxes than it did back in 2000 so it makes the state's revenue volatility a concern.

The top 1 percent of the state's personal income tax earners — roughly 164,000 tax returns — generate about half of the personal income taxes in California. A good chunk of the income from the wealthy comes from capital gains and stock options from companies in tech and other industries.

Meantime, Uber is reportedly planning to kick off its offering next month in a deal valuing the San Francisco-based company at a whopping $120 billion.

"When you're talking about Uber and its massive valuation, that's billions," said Chiang, a Democrat who ran unsuccessfully for governor in 2018.

Other Bay-area tech firms also could join the IPO parade, including Airbnb and Slack.

"A couple of years ago there were reports of over 100 unicorn companies in the San Francisco Bay Area, and how if they ever went public could create extraordinary wealth," said Chiang.

Chiang said new wealth in the Bay region from tech IPOs could increase housing market values in San Francisco and Silicon Valley. Yet he adds it also could worsen the region's affordability crisis.

"This is an incredible opportunity, and we need to use this as an example of California's prowess," he said. "But we also should have sensitivity to doing smart things to continue to be the engine for the 21st century economy."