California’s Proposition 13 cuts Bay Area homeowners’ property tax bills by up to tens of thousands of dollars a year. But in some parts of the region, the average homeowner isn’t benefiting quite as much as they once did.
The law saved San Francisco homeowners an average of roughly $9,000 in property taxes in 2025, according to a Chronicle analysis of data provided by real estate company Redfin. The city’s average home value was nearly $1.6 million that year, according to the brokerage, but its average assessed value — used to calculate homeowners’ tax bills — was just over $1 million.
That means the average San Francisco home was worth an estimated 52% more to the market than it was to the assessor’s office. But that gap was actually lower than it was in 2017, the earliest year for which Redfin has reliable data, when market values were more than double the average assessment. Market values were estimated by Redfin…