The U.S. city with the most expensive housing is San Francisco, California. This city consistently ranks at the top of various housing affordability indices due to a combination of factors including high demand, limited supply, and a strong local economy. According to a report by Zillow, the median home value in San Francisco reached $1.5 million in 2021, significantly higher than the national median of approximately $350,000. The high cost of living, driven by factors such as high-income jobs in the tech industry, a limited amount of developable land, and a robust rental market, contributes to the city's status as the most expensive housing market in the United States.