The 50 wealthiest U.S. counties by average household income feature a high concentration in Virginia, which has nine counties on the list. The top counties include San Mateo, Marin, and Santa Clara in California, with average incomes over $210,000 and typical home values exceeding $1.6 million. Other notable wealthy counties are in New York, Colorado, New Jersey, and Massachusetts, with home values ranging from around $500,000 to nearly $4.8 million.