Muir Beach, California Demographics & Population 2026

A note before these figures: with a population of 311, Muir Beach's ACS estimates come from a small number of survey responses and carry wide margins of error. Individual percentages below — particularly rates that round to 0% or 100% — are approximations, not precise measurements. See data.census.gov for the published margins of error.

Population Overview

Muir Beach is a small community located in California, within Marin County. The total population is 311. It ranks as the 1314th most populous out of 1,570 Census-designated places in California.

Age Demographics

The median age in Muir Beach is 63.7 years. This is 68% higher than the state median of 37.9 years. Only 6.8% of residents are under 18, indicating fewer families with children. 20.6% of residents are 75 or older, suggesting a significant retirement-age population with implications for healthcare services and senior housing.

Economy, Income & Housing

The median household income in Muir Beach is $140,227. This is 41% higher than the state median of $99,122. It is also 74% higher than the national median of $80,734. The poverty rate stands at 8.0%. This is 33% lower than the state poverty rate of 12.0%. The unemployment rate is 2.4%. This is 64% lower than the state rate of 6.6%. The median home value is $2,000,000+. Housing costs are 172% higher than the state median of $734,700. The home-value-to-income ratio of 14.3x suggests that housing affordability is a significant concern for many residents. 87.6% of occupied housing units are owner-occupied. This homeownership rate is 57% higher than the state average of 55.9%.

Race & Ethnicity

Muir Beach has a predominantly White (non-Hispanic) population, comprising 88.8% of all residents. The White (non-Hispanic) population is significantly higher than the state average (88.8% vs 33.8%).

Education

66.2% of residents aged 25 and older hold a bachelor's degree or higher. This places Muir Beach in the top 10% of all cities in the state for educational attainment. This is 78% higher than the state rate of 37.1%. Nationally, 35.7% of adults hold at least a bachelor's degree. No surveyed resident aged 25 or older reported leaving school before earning a high school diploma, though a rate of exactly 100% reflects the limits of a small sample. Notably, 37.5% of adults hold a graduate or professional degree, indicating a highly educated workforce.

Data Sources & Methodology

All demographic data for Muir Beach, California is sourced from the U.S. Census Bureau's American Community Survey (ACS) 2020–2024 5-Year Estimates. The ACS collects data from approximately 3.5 million households annually and pools five years of responses so that even small communities can be measured, though the margin of error widens as the population falls. Comparisons are made against California state averages and national averages calculated from the same dataset. Rankings reflect the city's position among all 1,570 Census-designated places in California. Read more about how these figures are produced on our methodology page, or visit data.census.gov for official data.