RANKING · 2020 CENSUS · 33 SHOWN OF 33

Most population lost, New Mexico counties · 2020

New Mexico counties that lost 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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SAME RANKING BYCities States Metros

YEAR2000 2010 2020 2025

RANKPLACESTATEPOPPOPULATION CHANGEVS 2000

01San Juan County, NMNM120,340-8,383−138%

02San Miguel County, NMNM26,260-2,192−150%

03Colfax County, NMNM12,184-1,363−208%

04Torrance County, NMNM16,100-1,338−120%

05Grant County, NMNM27,252-1,329−140%

06Socorro County, NMNM15,838-1,271−138%

07Hidalgo County, NMNM3,929-716+2654%

08Mora County, NMNM4,051-692−176%

09Roosevelt County, NMNM18,615-655−150%

10Chaves County, NMNM63,364-488−114%

11Union County, NMNM3,844-470−1040%

12Sierra County, NMNM11,395-412−112%

13Valencia County, NMNM82,013-364−102%

14De Baca County, NMNM1,647-324+2600%

15Quay County, NMNM8,454-295−56%

16Guadalupe County, NMNM4,343-235−145%

17Lincoln County, NMNM19,844-228−103%

18Catron County, NMNM3,827-146−115%

19Cibola County, NMNM26,807-41−102%

20Harding County, NMNM617-38−79%

21Curry County, NMNM46,655+54−98%

22Rio Arriba County, NMNM39,832+117−98%

23Luna County, NMNM25,407+332−95%

24McKinley County, NMNM68,119+1,410−90%

25Los Alamos County, NMNM19,407+1,469+544%

26Taos County, NMNM34,564+1,552−77%

27Otero County, NMNM70,368+4,042−61%

28Eddy County, NMNM62,509+8,485+178%

29Lea County, NMNM74,749+9,728−3930%

30Doña Ana County, NMNM229,091+10,328−74%

31Santa Fe County, NMNM156,907+10,653−65%

32Bernalillo County, NMNM667,601+13,880−82%

33Sandoval County, NMNM159,565+17,273−35%

SHOWING 1–33 OF 33

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