San Mateo County, CA Demographics

The total population of San Mateo County is estimated to be 754,250 with 376,542 males (49.92%) and 377,708 females (50.08%). There are 1,166 more females than males in San Mateo County.
The median household income in San Mateo County was $147,909 in 2021, which marked an an increase of 2,764(1.90%) from $145,145 in 2020. This income is 198.25% of the U.S. median household income of $74,606 (all incomes in 2022 inflation-adjusted dollars).
Per the latest American Community Survey by the Census Bureau, San Mateo County sees its highest median household income among householders in the age group of 45 to 64 years old, at $178,196. Overall, the median household income for the county of San Mateo County stands at $145,388.
In San Mateo County, the median income for all workers aged 15 years and older, regardless of work hours, was $72,266 for males and $52,071 for females. However, when specifically considering full-time, year-round workers within the same age group, the median income was $105,672 for males and $93,176 for females.
In San Mateo County, the demographic landscape is diverse, spanning 7 distinct racial categories among households. Among these, Asian households have the highest median household income at $174,457, while American Indian and Alaska Native households represent the opposite end with the lowest median household income of $63,799.
In 2022, the population of San Mateo County was 729,181, a 1.34% decrease year-by-year from 2021. Previously, in 2021, San Mateo County's population was 739,060, a decline of 3.08% compared to a population of 762,511 in 2020.
The median age in San Mateo County, CA is 40.0, as per 2021 ACS 5-Year Estimates. Of the total population, 16.92% were under the age of 15, 17.67% aged 15 to 29, 49.16% aged 30 to 64, 13.90% aged 65 to 84, and 2.34% were 85 years of age and older.
Racial distribution of San Mateo County population: 45.86% are White, 2.36% are Black or African American, 0.72% are American Indian and Alaska Native, 29.88% are Asian, 1.22% are Native Hawaiian and other Pacific Islander, 10.96% are some other race and 8.99% are multiracial.