Overview
262,387
Total Population
47.1
Median age
50.78%
Female population %
96.9:100
Gender ratio (M:F)
55-59 years
Largest age group
62.5
Total dependency ratio
White
Largest racial group
43,043
Hispanic population
Sources: U.S. Census Bureau, American Community Survey (ACS) 2021
TABLE OF CONTENTS
Age
Marin County's population is old compared to the rest of the country:
- The median age in Marin County is 47.1, compared to 38.8 nationwide, according to the American Community Survey 2017 - 2021 5 Year estimates.
- Marin County's population under 18 was 19.99%, compared to the 22.51% nationwide.
- Marin County's elderly or the senior population (over 65 age) was 22.36% as compared to 16.04% nationwide.
- Of the total population in Marin County, 16.10% were under the age of 15, 14.50% aged 15 to 29, 47.04% aged 30 to 64, 19.66% aged 65 to 84, and 2.70% were 85 years of age and older.
![Marin County, CA population by age group The graph shows Marin County's population by age group, with age group on x-axis and the respective age group's percent of the total population on y-axis](https://i.neilsberg.com/ch/marin-county-ca-population-by-age-group.jpeg)
Read more about Marin County, CA population by age ➔
Gender
There are 4,099 more females than males in Marin County:
- The female percentage in the USA is 50.50% while the male percentage is 49.50%, compared to 50.78% females and 49.22% males in Marin County, CA.
- The Marin County, CA gender ratio is 96.9:100 i.e. 96.9 men to 100 women (0.969).
- For male population, the largest age group is 50-54 years with a population of 10,203.
- For the female population, the largest age group is 55-59 years with a population of 11,302.
![Marin County, CA population by gender and age The grouped bar chart shows Marin County, CA population by age and gender across 18 age groups, defined between the age of 0 and 85 and above. The female population is shown in pink color bar and male population is shown in blue color bar. Age group is plotted on x axis and population on y axis.](https://i.neilsberg.com/ch/marin-county-ca-population-by-gender-and-age.jpeg)
Read more about Marin County, CA population by gender ➔
Race / Ethnicity
Marin County's population has become increasingly diverse:
- Racial distribution of Marin County population: 75.32% are White, 2.28% are Black or African American, 0.38% are American Indian and Alaska Native, 6.06% are Asian, 0.16% are Native Hawaiian and other Pacific Islander, 8.02% are some other race and 7.78% are multiracial.
- Marin County's racial breakdown clearly shows that there is an absolute majority of White population in the county.
- By ethnicity, 43,043 is Hispanic or Latino (of any race), and 219,344 (83.60% of the total population) is Non-Hispanic.
- The largest racial group in Marin County is White with a population of 197,622 (75.32% of the total population).
![Marin County, CA population by race The bar chart shows Marin County, CA population by race, in percentage. The numbers shown are based on the American Community Survey respondents self identified race. The Hispanic and Latino population is spread across the races identified and not as a separate race category.](https://i.neilsberg.com/ch/marin-county-ca-population-by-race.jpeg)
Read more about Marin County, CA population by race ➔
Year by year
Marin County's population has already reached its peak and is showing a trend of decline:
- The peak population was 261,282 in the year 2020
- From 2000 to 2010, Marin County's population increased by 5,306 (2.14%), as compared to the national growth of 9.63%.
- From 2010 to 2020, Marin County's population increased by 8,376 (3.31%), according to Census Bureau's Population Estimates Program. For the same period, the rate of growth for the United States was 7.17%.
- Between the year 2000 and 2022, Marin County's population was lowest in year 2004 at 244,410.
![Marin County, CA population from 2000 to 2022 The graph shows Marin County's population from 2000 to 2022, with years on x-axis and population on y-axis](https://i.neilsberg.com/ch/population-of-marin-county-ca-population-by-year-2000-2022.jpeg)
Read more about Marin County, CA population by year ➔
References
- U.S. Census Bureau American Community Survey (ACS) 2017-2021 5-Year Estimates
- U.S. Census Bureau Population Estimates Population Estimates Program (PEP)