How many people live in Los Alamos County, NM?
Updated Apr. 6, 2026Refreshed annually
In 2024, there were about 19,700 people living in Los Alamos County, NM. That makes Los Alamos County the 20th-most populous county in New Mexico. It is home to 0.93% of people living in the state.
19.7K
population of Los Alamos County, NM (2024)
0.93%
County share of the New Mexico population (2024)
About 19,700 people lived in Los Alamos County, NM in 2024.
Population estimates, 2000–2024
What are Los Alamos County, NM’s age demographics?
About 3,600 Los Alamos County residents are aged 65 and older in 2024. That represents 18.4% of its population. For comparison, the age group represents 20.3% of New Mexico’s population and 18% in the US overall.
Another 4,100 Los Alamos County residents, or 20.6% of the population, were children under 18. For comparison, the age group represents 21.2% of New Mexico’s population and 21.6% in the US overall.
A higher share of Los Alamos County, NM's population is aged 25–44 than the US as a whole.
Population estimates by age group, (2024)
What are Los Alamos County, NM’s racial and ethnic demographics?
Non-Hispanic white residents make up 69.6% of the Los Alamos County population, higher than the national share of 57.5%. Los Alamos County also has a larger share of people identifying as non-Hispanic Asian (7.5%) than the US overall (6.5%).
In contrast, Los Alamos County’s non-Hispanic Black or African American population accounts for 1.4%, below the 12.6% nationwide, and the Hispanic population makes up 18.5% of the county, compared with 20% nationally.
Racial and ethnic make up differ based on location. These figures reflect how people identified their race alone (not in combination with other races), and separate out Hispanic or Latino ethnicity, following Census reporting standards.
Los Alamos County, NM has a higher share of a non-Hispanic white population than New Mexico as a whole.
Population estimates by race and ethnicity, (2024)
Keep exploring
Methodology
USAFacts standardizes data, in areas such as time and demographics, to make it easier to understand and compare.
The analysis was generated with the help of AI and reviewed by USAFacts for accuracy.
Page sources
USAFacts endeavors to share the most up-to-date information available. We sourced the data on this page directly from government agencies; however, the intervals at which agencies publish updated data vary.
