11 of America’s 25 most expensive ZIP codes are in the Bay Area. Here’s where

Zillow estimated the value of this Atherton home at $8,249,232 in March 2019. (Randy Vazquez/Bay Area News Group)

The Bay Area, with its million-dollar views and multimillion-dollar enclaves, has kept its status as the most expensive metropolitan area in the United States.

The region’s ZIP codes make up 37 of the top 100 most expensive ZIP codes in the country, according to a new 2023 ranking by real estate data company PropertyShark that examined median home sales prices.

“The two biggest reasons Bay Area housing stands above the rest of the country are high incomes and limited homes,” said Orphe Divounguy, senior economist at Zillow. “There have not been enough homes built in the Bay Area to keep up with demand, which is true in much of the country but made worse in the Bay Area because there isn’t a whole lot of space available to build. That dynamic where demand is greater than supply has led buyers to compete for what’s available. And because there are a lot of high earners living in the Bay Area, there is extra heft behind those bidding wars.”

While the housing market nationally has experienced a slowdown, some wealthy, in-demand areas — including in the Bay Area — have seen prices tick up.

“The most exclusive areas in the country are still experiencing growth, defying the overall trend of declining prices,” according to the PropertyShark report.

Atherton’s tony 94027 ranked at the top of the list for the seventh year in a row, with an eye-popping median sales price of $8.3 million, an increase of 5% from last year’s $7.9 million. The city, just five square miles, is a hamlet for tech industry power players, as well as celebrities, including billionaire venture capitalist Marc Andreessen and Golden State Warriors star Stephen Curry.

Those notable names have created a cachet around Atherton, the San Mateo County town with one of the highest per capita incomes in the country.

“The level of sophistication of the people where we live is a big draw,” said Katy Thielke Straser, a real-estate agent with the Straser Silicon Valley Team with Compass.

The communities around Atherton on the Peninsula also command top dollar because of their proximity to top schools, both private and public.

“There’s just not a lot of dirt to build on, and everyone wants to be there,” said Thielke Straser. “Even with interest rates as high as they are, people are still trying to get into a house here, and that puts pressure on the market.”

Most lots in Atherton are more than an acre in size, about 43,560 square feet on average. Meanwhile, the average lot size in neighboring Menlo Park is closer to 10,000 square feet, said Veronica Kogler, an agent on the Peninsula with Coldwell Banker.

“Atherton’s larger lots allow people to build larger homes and offer homeowners greater privacy,” she said.

Still, several Bay Area ZIP codes dropped in the rankings. Last year, the Bay Area had a record 46 ZIP codes in the top 100. San Francisco only had three ZIP codes in the top 100 in 2023, a drop from the 13 it recorded in 2019.

“You hear about how expensive San Francisco is, but the houses in my area would blow the prices out of the water there,” Kogler said. “It’s only certain neighborhoods of San Francisco that command the top dollar amounts.”