Post Mountain, California Demographics & Population 2026

A note before these figures: with a population of 233, Post Mountain'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

Post Mountain is a small community located in California, within Trinity County. The total population is 233. It ranks as the 1358th most populous out of 1,570 Census-designated places in California.

Age Demographics

The median age in Post Mountain is 42.9 years. This is 13% higher than the state median of 37.9 years. 21.0% of residents are 75 or older, suggesting a significant retirement-age population with implications for healthcare services and senior housing.

Economy, Income & Housing

The ACS records no residents below the poverty line in Post Mountain. In a community this small the estimate rests on very few survey responses, so it should be read as an absence of measurement rather than a measured absence of poverty. The survey records no unemployed residents in Post Mountain, which reflects the size of the sample rather than a labor market without joblessness. 100.0% of occupied housing units are owner-occupied. This homeownership rate is 79% higher than the state average of 55.9%.

Race & Ethnicity

The largest racial or ethnic group in Post Mountain is White (non-Hispanic), making up 52.8% of the population. The White (non-Hispanic) population is significantly higher than the state average (52.8% vs 33.8%).

Education

79.0% of residents aged 25 and older hold a bachelor's degree or higher. This places Post Mountain in the top 10% of all cities in the state for educational attainment. This is 113% 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.

Data Sources & Methodology

All demographic data for Post Mountain, 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.