New Mexico Counties by Population (2025)
Top 5 Most Populous Counties
668,844
228,570
160,614
156,346
120,887
33 Counties
| County | 2025 Pop. ↓ | Area (mi²) | Density | Change (2020) |
|---|---|---|---|---|
| Bernalillo County | 668,844 | 1,161 | 576 | -1.18% |
| Doña Ana County | 228,570 | 3,808 | 60 | 3.87% |
| Sandoval County | 160,614 | 3,710 | 43 | 7.59% |
| Santa Fe County | 156,346 | 1,910 | 82 | 0.84% |
| San Juan County | 120,887 | 5,517 | 22 | -0.4% |
| Valencia County | 81,021 | 1,067 | 76 | 6.08% |
| Lea County | 71,617 | 4,392 | 16 | -4.05% |
| Otero County | 69,471 | 6,613 | 11 | 2.37% |
| McKinley County | 66,529 | 5,451 | 12 | -8.35% |
| Chaves County | 62,899 | 6,067 | 10 | -3.45% |
| Eddy County | 60,419 | 4,176 | 14 | -3.07% |
| Curry County | 46,806 | 1,406 | 33 | -3.23% |
| Rio Arriba County | 39,646 | 5,861 | 7 | -1.55% |
| Taos County | 34,035 | 2,202 | 15 | -1.24% |
| Grant County | 27,030 | 3,961 | 7 | -4.17% |
| Cibola County | 26,598 | 4,540 | 6 | -1.86% |
| San Miguel County | 26,200 | 4,722 | 6 | -3.43% |
| Luna County | 24,562 | 2,965 | 8 | -3.52% |
| Los Alamos County | 19,786 | 109 | 182 | 1.9% |
| Lincoln County | 19,401 | 4,831 | 4 | -4.46% |
| Roosevelt County | 18,645 | 2,446 | 8 | -2.63% |
| Torrance County | 16,133 | 3,345 | 5 | 7.11% |
| Socorro County | 15,667 | 6,646 | 2 | -5.34% |
| Colfax County | 12,221 | 3,758 | 3 | -1.06% |
| Sierra County | 11,516 | 4,181 | 3 | -0.4% |
| Quay County | 8,472 | 2,874 | 3 | -2.75% |
| Guadalupe County | 4,244 | 3,030 | 1 | -4.39% |
| Mora County | 4,075 | 1,926 | 2 | -2.77% |
| Union County | 3,928 | 3,825 | 1 | -3.51% |
| Catron County | 3,889 | 6,924 | 1 | 7.85% |
| Hidalgo County | 3,873 | 3,439 | 1 | -6.99% |
| De Baca County | 1,587 | 2,323 | 1 | -5.59% |
| Harding County | 630 | 2,125 | 0.30 | -3.52% |
Overview of New Mexico New Mexico Counties
There are 33 counties in New Mexico.
The most populous county in New Mexico is Bernalillo County, which has 678,701 residents. Bernalillo County is home to Albuquerque, the most populous city in the state and the state’s primary economic and business hub.
The second-most populous county in New Mexico is Doña Ana County, which has 217,522 people, followed by Santa Fe County, which is home to Santa Fe and has a population of 150,056. All three counties have grown since the 2010 Census, by 2.22%, 3.53%, 3.82% respectively.
Counties with Fewest Residents
Of New Mexico‘s 33 counties, Harding County has the fewest residents with just 655. This results in a population density of 0.31 persons per square kilometer. About 0.03% of New Mexico‘s total population lives in Harding County.
De Baca County has the second smallest population of 1,781 people, about 0.08% of the total population. The population density in De Baca County is still less than one person per square kilometer at 0.77 persons.
Catron County is the third-least populous county in New Mexico, with a population of 3,578 people. Catron County’s population comprises 0.17% of the state’s total population and its density is 0.52 persons per square kilometer.
Counties with Rapid Growth
None of New Mexico‘s counties have experienced double-digit growth since 2010. The county that has experienced the highest population growth is Sandoval County, which grew by 9.63%. This is followed by:
- Lea County (7.76%)
- Eddy County (7.42%)
The majority of New Mexico counties have experienced population loss since the 2010 Census. Hidalgo County has experienced the greatest population loss of 12.83%, followed by:
- De Baca County (12.22%)
- Colfax County (11.82%)
Sources
- US Census State Population Estimates - Most recent state estimates from the Census Bureau's Population Estimates Program
- US Census County Population Estimates - Most recent county estimates from the Census Bureau's Population Estimates Program
- American Community Survey (2009 - 2013)
- Census QuickFacts
- Historical Populations of States and Counties (1790 - 1990)