RANKING · 2020 CENSUS · 33 SHOWN OF 33

Most population gained, New Mexico counties · 2020

New Mexico counties that added the most residents from the 2010 census to 2020, 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+17,273−35%

02Bernalillo County, NMNM667,601+13,880−82%

03Santa Fe County, NMNM156,907+10,653−65%

04Doña Ana County, NMNM229,091+10,328−74%

05Lea County, NMNM74,749+9,728−3930%

06Eddy County, NMNM62,509+8,485+178%

07Otero County, NMNM70,368+4,042−61%

08Taos County, NMNM34,564+1,552−77%

09Los Alamos County, NMNM19,407+1,469+544%

10McKinley County, NMNM68,119+1,410−90%

11Luna County, NMNM25,407+332−95%

12Rio Arriba County, NMNM39,832+117−98%

13Curry County, NMNM46,655+54−98%

14Harding County, NMNM617-38−79%

15Cibola County, NMNM26,807-41−102%

16Catron County, NMNM3,827-146−115%

17Lincoln County, NMNM19,844-228−103%

18Guadalupe County, NMNM4,343-235−145%

19Quay County, NMNM8,454-295−56%

20De Baca County, NMNM1,647-324+2600%

21Valencia County, NMNM82,013-364−102%

22Sierra County, NMNM11,395-412−112%

23Union County, NMNM3,844-470−1040%

24Chaves County, NMNM63,364-488−114%

25Roosevelt County, NMNM18,615-655−150%

26Mora County, NMNM4,051-692−176%

27Hidalgo County, NMNM3,929-716+2654%

28Socorro County, NMNM15,838-1,271−138%

29Grant County, NMNM27,252-1,329−140%

30Torrance County, NMNM16,100-1,338−120%

31Colfax County, NMNM12,184-1,363−208%

32San Miguel County, NMNM26,260-2,192−150%

33San Juan County, NMNM120,340-8,383−138%

SHOWING 1–33 OF 33

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UPDATED 2026-07-15 · DATA: US CENSUS BUREAU DECENNIAL CENSUS