Newsom is not terming the program a vaccine "passport" or saying it will be required. But it will serve as an electronic version of the paper card that Americans receive when they get their COVID-19 shots.
"We'll be doing something that provides you the opportunity - we'll announce this later this week - to have an electronic version of your paper version of vaccination," Newsom said.
"It's not a passport, it's not a requirement. It's just the ability now to have an electronic version of that paper version."
As businesses throughout California reopen to full capacity this week, there have been concerns about mask enforcement. State and federal guidelines say unvaccinated customers and workers should still wear masks when indoors, but there is still uncertainy over how businesses will enforce that.
The standard paper cards handed out with vaccinations have been found to be easy to be forged.
In San Joaquin County, for example, a bar owner was arrested in May for allegedly making and selling fake cards for $20 each.
California bar owner arrested for selling fake vaccination cards
And state officials are warning Californians not to make or sell fake cards, a crime punishable as a federal offense.
Electronic verification of vaccination has been a controversial issue, with some critics fearing a mandatory "vaccine passport" that will violate privacy rights.
Orange County was working on an electronic verification program until hundreds of people showed up at a Board of Supervisors meeting to protest, many of them citing privacy concerns and others touting conspiracy theories about tracking.
Orange County vaccine passport plan on hold after protests