Top 10 most populous counties
Los Angeles County leads with 9,848,406. The 10 US counties with the largest population, from US Census ACS 2023 5-year estimates.
| # | Name | Population |
|---|---|---|
| 1 | Los Angeles County · CA | 9,848,406 |
| 2 | Cook County · IL | 5,185,812 |
| 3 | Harris County · TX | 4,758,579 |
| 4 | Maricopa County · AZ | 4,491,987 |
| 5 | San Diego County · CA | 3,282,782 |
| 6 | Orange County · CA | 3,164,063 |
| 7 | Miami-Dade County · FL | 2,685,296 |
| 8 | Kings County · NY | 2,646,306 |
| 9 | Dallas County · TX | 2,603,816 |
| 10 | Riverside County · CA | 2,449,909 |
Methodology
Total population (ACS 2023 5-year). Universe: 3,137 US counties with population > 0.
As of 2026-05-28. ACS 2023 5-year + CBP 2022.
Related rankings
- Top 10 wealthiest counties (median household income) — #1 Loudoun County ($178,707)
- Top 10 lowest-income counties — #1 Randolph County ($25,425)
- Top 10 highest median home value counties — #1 San Mateo County ($1,494,500)
- Top 10 lowest median home value counties — #1 Todd County ($45,200)
- Top 10 most rural counties (lowest population) — #1 Kenedy County (52)
- Top 10 cheapest-rent states — #1 West Virginia ($866/mo)
- Top 10 most-expensive-rent states — #1 Hawaii ($2,057/mo)
- Top 10 oldest-population states — #1 Florida (42.2 yrs)
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