
Rio Arriba County
- State:
- New Mexico
Rio Arriba County's estimated 2025 population is 39,646 with a growth rate of -0.29% in the past year according to the most recent United States census data. Rio Arriba County is the 13th largest county in New Mexico. The 2010 population was 40,286 and has seen a growth of -1.59% since that time.