San Marcos Population 2025. Read the full san marcos community profile to gain insights and information about demographics, socioeconomics, the housing market and the economy in the city of san marcos. Between 2021 and 2022 the population of san marcos, ca grew from 94,313 to 94,360, a 0.0498% increase and its median household income grew from $90,620 to $99,413, a 9.7% increase.
Full demographic report of san marcos, ca population including education levels, household income, job market, ethnic makeup, and languages. The san marcos population is 96,219, with a population density of 3,917 people per square mile, diverging from the national average of 91.