Counties of New Mexico
LocationState of New Mexico
Populations624 (Harding) – 671,586 (Bernalillo)
Areas109 square miles (280 km2) (Los Alamos) – 6,928 square miles (17,940 km2) (Catron)

There are 33 counties in the U.S. state of New Mexico.

The New Mexico Territory was organized in September 1850. The first nine counties in the territory to be created, in 1852, were Bernalillo, Doña Ana, Rio Arriba, San Miguel, Santa Ana, Santa Fe, Socorro, Taos, and Valencia Counties. Mora County was created in 1860. Following the Gadsden Purchase of 1853–1854, the northeasternmost part of the New Mexico Territory was ceded to the new Colorado Territory in February 1861, before the western half was reorganized as the Arizona Territory in February 1863, establishing New Mexico's present-day boundaries.

Grant County was created in 1868, followed by Colfax and Lincoln Counties in 1869. In 1876, Santa Ana County was absorbed by Bernalillo County. A further 14 counties were then created between 1884 and 1909, bringing the total number to 26.

New Mexico was admitted to the Union as the 47th state on January 6, 1912. De Baca and Lea Counties were created in 1917, followed by Hidalgo County in 1920 and Catron and Harding Counties in 1921. Los Alamos County was created in 1949 and finally Cibola County in 1981, bringing the total number of counties to 33.

The Federal Information Processing Standard (FIPS) code, which is used by the United States government to uniquely identify states and counties, is provided with each entry.[1] New Mexico's code is 35, which when combined with any county code would be written as 35XXX. The FIPS code for each county links to census data for that county.


See also: List of New Mexico counties by socioeconomic factors

For comparison, the population estimate for the state of New Mexico as of July 2011 was 2,082,224, and the area was 121,589 mi2 (315,194 km2).

County FIPS code
County seat
Formed from
Bernalillo County 001 Albuquerque 1852 One of the nine original counties. The Gonzales-Bernal family, Spanish nobles who settled the territory in the seventeenth century 671,586 1,166 sq mi
(3,020 km2)
State map highlighting Bernalillo County
Catron County 003 Reserve 1921 Part of Socorro County. Thomas Benton Catron (1840-1921), a Santa Fe attorney and New Mexico's first U.S. Senator 3,825 6,928 sq mi
(17,943 km2)
State map highlighting Catron County
Chaves County 005 Roswell 1889 Part of Lincoln County. Jose Francisco Chaves (1833-1904), a U.S. Army colonel in New Mexico during and after the Civil War 63,561 6,071 sq mi
(15,724 km2)
State map highlighting Chaves County
Cibola County 006 Grants 1981 Parts of Valencia County, Socorro County, McKinley County, and Catron County. The mythical Seven Cities of Cibola 26,780 4,540 sq mi
(11,759 km2)
State map highlighting Cibola County
Colfax County 007 Raton 1869 Part of Mora County. Schuyler Colfax (1823-1885), the seventeenth vice president of the United States 12,255 3,757 sq mi
(9,731 km2)
State map highlighting Colfax County
Curry County 009 Clovis 1909 Parts of Quay County and Roosevelt County. George Curry (1861-1947), a governor of New Mexico Territory from 1907 to 1910 47,222 1,406 sq mi
(3,642 km2)
State map highlighting Curry County
De Baca County 011 Fort Sumner 1917 Parts of Chaves County and Guadalupe County. Ezequiel Cabeza de Baca (1864-1917), the second state governor of New Mexico 1,657 2,325 sq mi
(6,022 km2)
State map highlighting De Baca County
Doña Ana County 013 Las Cruces 1852 One of the nine original counties. Doña Ana Robledo, a seventeenth-century Spanish woman known for her charitable giving to the native population 225,210 3,807 sq mi
(9,860 km2)
State map highlighting Doña Ana County
Eddy County 015 Carlsbad 1887 Part of Lincoln County. Charles Eddy (1857 - 1931), a rancher and developer of the area 60,275 4,182 sq mi
(10,831 km2)
State map highlighting Eddy County
Grant County 017 Silver City 1868 Part of Doña Ana County. Ulysses Simpson Grant (1822-1885), the Civil War general and eighteenth president of the United States 27,472 3,966 sq mi
(10,272 km2)
State map highlighting Grant County
Guadalupe County 019 Santa Rosa 1891 Part of San Miguel County. Our Lady of Guadalupe, the patron saint of the Americas 4,292 3,031 sq mi
(7,850 km2)
State map highlighting Guadalupe County
Harding County 021 Mosquero 1921 Parts of Mora County and Union County. Warren Gamaliel Harding (1865-1923), the twenty-ninth president of the United States 624 2,126 sq mi
(5,506 km2)
State map highlighting Harding County
Hidalgo County 023 Lordsburg 1920 Part of Grant County. The Treaty of Guadalupe Hidalgo, named after a Mexican town in turn named for Miguel Hidalgo y Costilla (1753 - 1811), the priest who is known as the Father of Mexican Independence 3,965 3,446 sq mi
(8,925 km2)
State map highlighting Hidalgo County
Lea County 025 Lovington 1917 Parts of Chaves County and Eddy County. Joseph Calloway Lea (1841-1904), a captain in the U.S. Army and the founder of the New Mexico Military Academy 72,101 4,393 sq mi
(11,378 km2)
State map highlighting Lea County
Lincoln County 027 Carrizozo 1869 Part of Socorro County. Abraham Lincoln (1809-1865), the sixteenth president of the United States 20,029 4,831 sq mi
(12,512 km2)
State map highlighting Lincoln County
Los Alamos County 028 Los Alamos 1949 Parts of Sandoval County and Santa Fe County. Named for its county seat of Los Alamos, New Mexico, which itself is the Spanish name for the cottonwood tree 19,444 109 sq mi
(282 km2)
State map highlighting Los Alamos County
Luna County 029 Deming 1901 Parts of Doña Ana County and Grant County. Solomon Luna (1858 - 1912), the largest land owner in the county at the time of its creation; itself Spanish for moon 25,316 2,965 sq mi
(7,679 km2)
State map highlighting Luna County
McKinley County 031 Gallup 1899 Part of Bernalillo County. William McKinley (1843-1901), the twenty-fifth president of the United States 68,797 5,449 sq mi
(14,113 km2)
State map highlighting McKinley County
Mora County 033 Mora 1860 Part of Taos County. Named for its county seat of Mora, New Mexico, which is itself named after lo de mora, the Spanish term for blackberry 4,123 1,931 sq mi
(5,001 km2)
State map highlighting Mora County
Otero County 035 Alamogordo 1899 Parts of Doña Ana County and Lincoln County. Miguel A. Otero (1829-1882), territorial delegate to U. S. Congress or Miguel Antonio Otero (II) (1859-1944), 16th Governor of New Mexico Territory from 1897 to 1906 68,835 6,627 sq mi
(17,164 km2)
State map highlighting Otero County
Quay County 037 Tucumcari 1903 Part of Guadalupe County. Matthew Stanley Quay (1833-1904), a U.S. Senator from Pennsylvania who supported New Mexico's statehood 8,510 2,855 sq mi
(7,394 km2)
State map highlighting Quay County
Rio Arriba County 039 Tierra Amarilla 1852 One of the nine original counties. Named for its location on the upper Rio Grande (Río Arriba means "upstream" or "up the river" in Spanish) 39,876 5,858 sq mi
(15,172 km2)
State map highlighting Rio Arriba County
Roosevelt County 041 Portales 1903 Parts of Chaves County and Guadalupe County. Theodore Roosevelt (1858-1919), the twenty-sixth president of the United States 18,787 2,449 sq mi
(6,343 km2)
State map highlighting Roosevelt County
Sandoval County 043 Bernalillo 1903 Part of Bernalillo County. Named for the Sandoval family, prominent seventeenth-century Spanish landowners 155,936 3,710 sq mi
(9,609 km2)
State map highlighting Sandoval County
San Juan County 045 Aztec 1887 Part of Rio Arriba County. San Juan River, itself named after the Catholic saint 120,675 5,514 sq mi
(14,281 km2)
State map highlighting San Juan County
San Miguel County 047 Las Vegas 1852 One of the nine original counties. San Miguel de Bado Catholic Church, the first in the area 26,668 4,717 sq mi
(12,217 km2)
State map highlighting San Miguel County
Santa Fe County 049 Santa Fe 1852 One of the nine original counties. Named after the city of Santa Fe whose full Spanish name is “La Villa Real de la Santa Fe de San Francisco de Assisi” or “The royal city of the holy faith of St. Francis of Assisi” 155,956 1,909 sq mi
(4,944 km2)
State map highlighting Santa Fe County
Sierra County 051 Truth or Consequences 1884 Parts of Doña Ana County and Socorro County. Possibly named for the Black Range. (Sierra is mountain range in Spanish.) 11,488 4,180 sq mi
(10,826 km2)
State map highlighting Sierra County
Socorro County 053 Socorro 1852 One of the nine original counties. Spanish term meaning "aid," which refers to the help Native Americans gave to starving travelers 15,963 6,647 sq mi
(17,216 km2)
State map highlighting Socorro County
Taos County 055 Taos 1852 One of the nine original counties. Named for its county seat of Taos, New Mexico, which in turn was named for the nearby Taos Pueblo, an ancient Native American village. Taos is red willow in the Tiwa language 34,405 2,203 sq mi
(5,706 km2)
State map highlighting Taos County
Torrance County 057 Estancia 1903 Parts of Bernalillo County, Valencia County, and Socorro County. Francis J. Torrance (1859 - 1919), the developer of the New Mexico Central Railroad 15,633 3,345 sq mi
(8,664 km2)
State map highlighting Torrance County
Union County 059 Clayton 1893 Parts of Colfax County, Mora County and San Miguel County. Named for the "union" of the three counties which donated land to form the new county 3,964 3,830 sq mi
(9,920 km2)
State map highlighting Union County
Valencia County 061 Los Lunas 1852 One of the nine original counties. Named for the town of Valencia, New Mexico, which is itself named for Valencia, Spain 79,141 1,068 sq mi
(2,766 km2)
State map highlighting Valencia County

Former counties


  1. ^ "FIPS Publish 6-4". National Institute of Standards and Technology. Archived from the original on September 29, 2013. Retrieved August 6, 2007.
  2. ^ "EPA County FIPS Code Listing". US Environmental Protection Agency. Retrieved August 6, 2007.
  3. ^ a b c "NACo - Find a county". National Association of Counties. Archived from the original on September 30, 2007. Retrieved August 7, 2007.
  4. ^ "NMGenWeb Counties". Archived from the original on July 2, 2007. Retrieved August 6, 2007.
  5. ^ Viva New Mexico County Names Archived July 4, 2008, at the Wayback Machine
  6. ^ "U.S. Census Bureau QuickFacts: New Mexico". U.S. Census Bureau. Retrieved April 20, 2024.
  7. ^ "New Mexico QuickFacts". U.S. Census Bureau. Archived from the original on December 27, 2011. Retrieved August 7, 2007. (2000 Census)
  8. ^ "Territory of New Mexico" (PDF). United States Census Bureau. 1860.