RANKING · 2025 ESTIMATES · 33 SHOWN OF 33

Most population lost, New Mexico counties

New Mexico counties that lost 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. The median across all 33 is -181. Biggest climber in the top 100 since 2020: Bernalillo County, NM, up 31 places to #1.

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New MexicoAll states All rankings

SAME RANKING BYCities States Metros

YEAR2000 2010 2020 2025

RANKPLACESTATEPOPPOPULATION CHANGEVS 2000

01▲31Bernalillo County, NMNM667,601-8,843−112%

02▲22McKinley County, NMNM68,119-4,783−134%

03▲7Chaves County, NMNM63,364-1,793−151%

04▲17Curry County, NMNM46,655-1,775−163%

05▼4San Juan County, NMNM120,340-1,321−106%

06▼4San Miguel County, NMNM26,260-941−121%

07▼2Grant County, NMNM27,252-933−128%

08▼2Socorro County, NMNM15,838-757−123%

09Roosevelt County, NMNM18,615-576−144%

10▲12Rio Arriba County, NMNM39,832-531−108%

11▲6Lincoln County, NMNM19,844-425−106%

12▲7Cibola County, NMNM26,807-365−120%

13▲2Quay County, NMNM8,454-292−56%

14▼7Hidalgo County, NMNM3,929-249+858%

15▼4Union County, NMNM3,844-235−570%

16▼13Colfax County, NMNM12,184-203−116%

17▼5Sierra County, NMNM11,395-181−105%

18▼10Mora County, NMNM4,051-138−115%

19▼3Guadalupe County, NMNM4,343-109−121%

20▼6De Baca County, NMNM1,647-51+325%

21▼1Harding County, NMNM617-40−77%

22▲1Luna County, NMNM25,407-20−100%

23▲2Los Alamos County, NMNM19,407-12−105%

24▲2Taos County, NMNM34,564+75−99%

25▲3Eddy County, NMNM62,509+195−94%

26▼8Catron County, NMNM3,827+248−75%

27▲2Lea County, NMNM74,749+294−216%

28▼24Torrance County, NMNM16,100+1,055−84%

29▲2Santa Fe County, NMNM156,907+2,084−93%

30▼3Otero County, NMNM70,368+2,529−76%

31▼18Valencia County, NMNM82,013+5,808−72%

32▼2Doña Ana County, NMNM229,091+9,530−76%

33Sandoval County, NMNM159,565+10,731−60%

SHOWING 1–33 OF 33

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UPDATED 2026-09-11 · DATA: US CENSUS BUREAU POPULATION ESTIMATES