RANKING · 2025 ESTIMATES · 33 SHOWN OF 33

Most population gained, New Mexico counties

New Mexico counties that added the most residents from the 2020 census to 2025, by raw count of people rather than percentage. This list covers the 33 counties in New Mexico that qualify, ranked against each other statewide.

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New MexicoAll states All rankings

SAME RANKING BYCities States Metros

YEAR2000 2010 2020 2025

RANKPLACESTATEPOPPOPULATION CHANGEVS 2000

01Sandoval County, NMNM159,565+10,731−60%

02Doña Ana County, NMNM229,091+9,530−76%

03Valencia County, NMNM82,013+5,808−72%

04Otero County, NMNM70,368+2,529−76%

05Santa Fe County, NMNM156,907+2,084−93%

06Torrance County, NMNM16,100+1,055−84%

07Lea County, NMNM74,749+294−216%

08Catron County, NMNM3,827+248−75%

09Eddy County, NMNM62,509+195−94%

10Taos County, NMNM34,564+75−99%

11Los Alamos County, NMNM19,407-12−105%

12Luna County, NMNM25,407-20−100%

13Harding County, NMNM617-40−77%

14De Baca County, NMNM1,647-51+325%

15Guadalupe County, NMNM4,343-109−121%

16Mora County, NMNM4,051-138−115%

17Sierra County, NMNM11,395-181−105%

18Colfax County, NMNM12,184-203−116%

19Union County, NMNM3,844-235−570%

20Hidalgo County, NMNM3,929-249+858%

21Quay County, NMNM8,454-292−56%

22Cibola County, NMNM26,807-365−120%

23Lincoln County, NMNM19,844-425−106%

24Rio Arriba County, NMNM39,832-531−108%

25Roosevelt County, NMNM18,615-576−144%

26Socorro County, NMNM15,838-757−123%

27Grant County, NMNM27,252-933−128%

28San Miguel County, NMNM26,260-941−121%

29San Juan County, NMNM120,340-1,321−106%

30Curry County, NMNM46,655-1,775−163%

31Chaves County, NMNM63,364-1,793−151%

32McKinley County, NMNM68,119-4,783−134%

33Bernalillo County, NMNM667,601-8,843−112%

SHOWING 1–33 OF 33

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UPDATED 2026-07-15 · DATA: US CENSUS BUREAU POPULATION ESTIMATES