Discover the 5 Richest Counties in Northern California

California is well-known for being an economic powerhouse. It has the highest gross domestic product (GDP) of any U.S. state by far. According to the Bureau of Economic Analysis, California’s gross domestic product (GDP) in 2022 was $3.6 trillion. That’s a whopping $1.2 trillion more than Texas, which had the second-highest GDP at $2.4 trillion. Despite California’s massive economy, there is a stark divide between the wealthy and the non-wealthy residents. In fact, according to the Public Policy Institute of California, the state ranks fourth in the U.S. for income inequality as of 2021. Their report also states that 20% of California’s wealth is concentrated in just 30 of its nearly 2,000 zip codes. This article explores the five richest counties in Northern California. They are ranked by their overall wealth index, which combines median income, investment income, and median home value.

California is home to five of the ten wealthiest counties in the United States. All of the richest counties in Northern California are in the San Francisco Bay Area, which is home to the high-technology hub known as Silicon Valley. Many of the most valuable high-technology corporations have their headquarters in Silicon Valley. This article explores which major corporations are in each of Northern California’s richest counties, as well as notable people from there.

1. San Mateo County

San Mateo County is not only the richest county in Northern California, but also in the entire U.S. It is in the southern San Francisco Bay Area, bordering San Francisco County to the north, Santa Clara County to the east, and Santa Cruz County to the south. San Mateo County’s population is 729,181. Its largest city is San Mateo, with a population of 100,984.

A few of the most valuable corporations in San Mateo County are Meta Platforms (formerly Facebook), Sony Interactive Entertainment, and Visa Inc. Some notable people from San Mateo County are the NFL player and coach John Madden, the actress Linda Cardellini, and the singer Stevie Nicks. San Mateo County is also home to Larry Ellison, the founder of Oracle Corportation and third-richest person in the U.S.

The median income of San Mateo County is $136,837, the investment income is $149,818, and the median home value is $1,495,191.

2. San Francisco County

San Francisco is a consolidated city-county and the namesake of the entire region surrounding the San Francisco Bay. The city is on a peninsula, bordering San Mateo County to the south and the Pacific Ocean on all other sides. San Francisco’s population is 808,437. With an area of just 49.6 square miles, it is one of the most densely populated cities in the U.S.

San Francisco has a massive Financial District with major companies including Wells Fargo, Salesforce, and Uber. Some notable people from San Francisco include Steve Jobs, the co-founder of Apple Inc., and Peter Thiel, the co-founder of PayPal.

The median income of San Francisco is $126,187, the investment income is $134,035, and the median home value is $1,272,795.

3. Santa Clara County

Santa Clara County is in the southern San Francisco Bay Area. It borders Santa Cruz and San Mateo Counties to the west, and Alameda County to the north. Santa Clara County’s population is 1,870,945, making it the most populous county in Northern California. San Jose, the county seat of Santa Clara County, is the third-most populous city in California with a population of 971,233.

Santa Clara County is home to many of the most valuable corporations in the world, including Apple Inc., Cisco Systems, and Intel. Some notable people from Santa Clara County include Steve Wozniak, the co-founder of Apple Inc., and Joan Baez, the folk singer and musician.

The median income of Santa Clara County is $140,258, the investment income is $90,292, and the median home value is $1,468,206.

4. Marin County

Marin County is in the northern San Francisco Bay Area, just across the Golden Gate Bridge from San Francisco. Its population is 256,018, making it the second-least populous county in the San Francisco Bay Area after Napa County. Two large corporations in Marin County are BioMarin Pharmaceutical and THX.

The median income of Marin County is $131,008, the investment income is $142,305, and the median home value is $1,428,578.

5. Alameda County

Alameda County is in the eastern San Francisco Bay Area, also known as the East Bay. It borders Santa Clara County to the south and San Francisco Bay to the west. Its population is 1,628,997, making it the second-most populous Northern California county behind Santa Clara. Oakland is the county seat and most populous city with 430,553.

Several highly value corporations are in Alameda County, including Kaiser Permanente, Clorox, and Pandora Radio. Some notable people from Alameda County are Vice President Kamala Harris, actress Zendaya Coleman, actor Mahershala Ali, and rapper MC Hammer.

The median income of Alameda County is $112,017, the investment income is $38,318, and the median home value is $1,067,823.

Summary of the Richest Counties in Northern California