Los Alamos County Flag

Los Alamos County

State:
New Mexico
County Seat:
Los Alamos

Los Alamos County's estimated 2026 population is 19,387 with a growth rate of -0.1% in the past year according to the most recent United States census data. Los Alamos County is the 20th largest county in New Mexico. The 2010 population was 17,995 and has seen a growth of 7.74% since that time.

19,387
Total Population
178
Population Density (mi²)
20
Population Rank (State)
-20 -0.1%
Annual Population Growth

Los Alamos County Population

Demographics

Economics and Income Statistics