Waterloo, California Demographics & Population 2026

A note before these figures: with a population of 894, Waterloo'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

Waterloo is a small community located in California, within San Joaquin County. The total population is 894. It ranks as the 1093rd most populous out of 1,570 Census-designated places in California.

Age Demographics

The median age in Waterloo is 40.5 years. This is 7% higher than the state median of 37.9 years. Only 12.1% of residents are under 18, indicating fewer families with children.

Economy, Income & Housing

The median household income in Waterloo is $221,850. This is 124% higher than the state median of $99,122. It is also 175% higher than the national median of $80,734. The poverty rate stands at 5.5%. This is 54% lower than the state poverty rate of 12.0%. The survey records no unemployed residents in Waterloo, which reflects the size of the sample rather than a labor market without joblessness. The median home value is $847,800. Housing costs are 15% higher than the state median of $734,700. The home-value-to-income ratio is 3.8x. 35.9% of occupied housing units are owner-occupied. This homeownership rate is 36% lower than the state average of 55.9%.

Race & Ethnicity

Waterloo has a predominantly White (non-Hispanic) population, comprising 88.7% of all residents. Hispanic or Latino residents account for 11.0%. The White (non-Hispanic) population is significantly higher than the state average (88.7% vs 33.8%). The Hispanic or Latino population (11.0%) is well below the state average of 40.2%.

Education

20.3% of residents aged 25 and older hold a bachelor's degree or higher. This is 45% lower than the state rate of 37.1%. Nationally, 35.7% of adults hold at least a bachelor's degree. The high school graduation rate (or equivalent) is 94.1%.

Data Sources & Methodology

All demographic data for Waterloo, 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.