- In January 2016, the county population increased substantially by 12,918 from 2015, a 10% increase compared to the low of 699,277 in 2005.
- Separate from data reported above, the Center for Migration Studies estimates that there were 57,000 undocumented residents in the county in 2014.
- In 2016, natural increase (number of births minus number of deaths) added 4,118 residents to San Mateo County, 10% lower than the year prior.
- Net migration is a combination of foreign immigration (legal and unauthorized foreign immigration, as well as residents leaving the county to live abroad), and domestic migration (people moving within the United States to and from San Mateo County). In July 2016, the county added 4,866 residents through foreign immigration and lost 5,241 residents to domestic migration.
- In 2016, the only county in the Bay Area to have a loss in net migration was San Mateo County. For all other counties and the state overall, net foreign immigration balanced the loss in net domestic migration.
- San Mateo County is projected to add approximately 106,504 residents by 2040, while the Bay Area is projected to grow by over 1 million people.
- Calculations made by the Association of Bay Area Governments (ABAG) and Plan Bay Area project even higher population growth between now and 2040. According to their forecasts, San Mateo County will add 185,000 residents and the Bay Area will grow by 2 million.
- Planning now for additional housing and transportation to accommodate the region’s growth is essential.
- As our population ages, the share of residents 65 and older is projected to nearly double. By 2040, nearly one in four county residents is expected to be 65 and older.
- The composition of the county by race/ethnicity will also change over the next twenty years, with the most pronounced growth expected in the share of total population that is Hispanic/Latino.
Center for Migration Studies. (2017). San Mateo County (Data Query). Retrieved from
State of California, Department of Finance. (2017). E-1 Report (Data File). Retrieved from http://www.dof.ca.gov/Forecasting/Demographics/Estimates/E-1/
State of California, Department of Finance. (2017). E-6 Report (Data File). Retrieved from http://www.dof.ca.gov/Forecasting/Demographics/Estimates/E-6/