San Marcos, Texas Demographics & Population 2026

Population Overview

San Marcos is a mid-sized community located in Texas, within Hays County. The total population is 70,897. It ranks as the 59th most populous out of 1,795 Census-designated places in Texas.

Age Demographics

The median age in San Marcos is 25.5 years. This is 28% lower than the state median of 35.6 years. Only 13.3% of residents are under 18, indicating fewer families with children.

Economy, Income & Housing

The median household income in San Marcos is $51,281. This is 35% lower than the state median of $78,476. It is also 36% lower than the national median of $80,734. The poverty rate stands at 26.9%. This is 95% higher than the state poverty rate of 13.8%. With more than one in five residents living below the poverty line, economic hardship is a significant challenge for the community. The unemployment rate is 5.2%. This is 2% lower than the state rate of 5.3%. The median home value is $310,400. Housing costs are 9% higher than the state median of $283,800. The home-value-to-income ratio of 6.1x suggests that housing affordability is a significant concern for many residents. 30.8% of occupied housing units are owner-occupied. This homeownership rate is 51% lower than the state average of 62.6%.

Race & Ethnicity

San Marcos is a highly diverse community where no single racial or ethnic group constitutes a majority of the population. Hispanic or Latino residents account for 42.2%. The Black or African American population (5.2%) is well below the state average of 11.9%. The Asian population (2.1%) is well below the state average of 5.5%.

Education

38.3% of residents aged 25 and older hold a bachelor's degree or higher. This is 13% higher than the state rate of 33.8%. Nationally, 35.7% of adults hold at least a bachelor's degree. The high school graduation rate (or equivalent) is 90.5%.

Data Sources & Methodology

All demographic data for San Marcos, Texas 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 Texas state averages and national averages calculated from the same dataset. Rankings reflect the city's position among all 1,795 Census-designated places in Texas. Read more about how these figures are produced on our methodology page, or visit data.census.gov for official data.