Largest Counties by Population

This is a comprehensive listing of the 44 counties in the United States with a population greater than one million, ranked by population. The data for this list is based on mid-2014 population estimates from the United States Census Bureau. A decade ago, only 38 counties in the U.S. had a population of more than one million and Los Angeles County had less than ten million residents. The top five list hasn't had much change although San Diego County knocked Orange County out of fifth place.

 

From this list, you can see that while much of the country's population is concentrated in the Megalopolis region of the Northeast, there is considerable population in the metropolitan regions of the Sunbelt from Texas to California. These heavily populated cities of Texas, Arizona, and California continue to experience phenomenal growth as population declines in places like the Rust Belt continue. 

 

1. Los Angeles County, CA - 10,116,705

2. Cook County, IL - 5,246,456

3. Harris County, TX - 4,441,370

4. Maricopa County, AZ - 4,087,191

5. San Diego County, California - 3,263,431

6. Orange County, California - 3,145,515

7. Miami-Dade County, Florida - 2,662,874

8. Kings County, New York - 2,621,793

9. Dallas County, Texas - 2,518,638

10. Riverside County, California - 2,329,271

11. Queens County, New York - 2,321,580

12. San Bernardino County, California - 2,112,619

13. King County, Washington - 2,079,967

14. Clark County, Nevada - 2,069,681

15. Tarrant County, Texas - 1,945,360

16. Santa Clara County, California - 1,894,605

17. Broward County, Florida - 1,869,235

18. Bexar County, Texas - 1,855,866

19. Wayne County, Michigan - 1,764,804

20. New York County, New York - 1,636,268

21. Alameda County, California - 1,610,921

22. Middlesex County, Massachusetts - 1,570,315

23. Philadelphia County, Pennsylvania - 1,560,297

24. Suffolk County, New York - 1,502,968

25. Sacramento County, California - 1,482,026

26. Bronx County, New York - 1,438,159

27. Palm Beach County, Florida - 1,397,710

28. Nassau County, New York - 1,358,627

29. Hillsborough County, Florida - 1,316,298

30. Cuyahoga County, Ohio - 1,259,828

31. Orange County, Florida - 1,253,001

32. Oakland County, Michigan - 1,237,868

33. Franklin County, Ohio - 1,231,393

34. Allegheny County, Pennsylvania - 1,231,255

35. Hennepin County, Minnesota - 1,212,064

36. Travis County, Texas - 1,151,145

37. Fairfax County, Virginia - 1,137,538

38. Contra Costa County, California - 1,111,339

39. Salt Lake County, Utah - 1,091,742

40. Montgomery County, Maryland - 1,030,447

41. Mecklenburg County, North Carolina - 1,012,539

42. Pima County, Arizona - 1,004,516

43. St. Louis County, Missouri - 1,001,876