#23. Sweetwater County

- 2010 to 2020 population change: -1,534
--- #2,717 among all counties nationwide
- 2010 to 2020 percent population change: -3.5%
--- #17 among counties in Wyoming, #2,077 among all counties nationwide
- 2020 population: 42,272
--- #4 largest county in Wyoming, #1,138 largest county nationwide

#22. Sublette County

- 2010 to 2020 population change: -1,519
--- #2,711 among all counties nationwide
- 2010 to 2020 percent population change: -14.8%
--- #23 among counties in Wyoming, #3,048 among all counties nationwide
- 2020 population: 8,728
--- #16 largest county in Wyoming, #2,509 largest county nationwide

#21. Carbon County

- 2010 to 2020 population change: -1,348
--- #2,661 among all counties nationwide
- 2010 to 2020 percent population change: -8.5%
--- #21 among counties in Wyoming, #2,750 among all counties nationwide
- 2020 population: 14,537
--- #12 largest county in Wyoming, #2,115 largest county nationwide

#20. Fremont County

- 2010 to 2020 population change: -889
--- #2,434 among all counties nationwide
- 2010 to 2020 percent population change: -2.2%
--- #15 among counties in Wyoming, #1,882 among all counties nationwide
- 2020 population: 39,234
--- #5 largest county in Wyoming, #1,195 largest county nationwide

#19. Washakie County

- 2010 to 2020 population change: -848
--- #2,409 among all counties nationwide
- 2010 to 2020 percent population change: -9.9%
--- #22 among counties in Wyoming, #2,860 among all counties nationwide
- 2020 population: 7,685
--- #19 largest county in Wyoming, #2,599 largest county nationwide

#18. Goshen County

- 2010 to 2020 population change: -751
--- #2,359 among all counties nationwide
- 2010 to 2020 percent population change: -5.7%
--- #20 among counties in Wyoming, #2,427 among all counties nationwide
- 2020 population: 12,498
--- #14 largest county in Wyoming, #2,239 largest county nationwide

#17. Uinta County

- 2010 to 2020 population change: -668
--- #2,302 among all counties nationwide
- 2010 to 2020 percent population change: -3.2%
--- #16 among counties in Wyoming, #2,025 among all counties nationwide
- 2020 population: 20,450
--- #10 largest county in Wyoming, #1,795 largest county nationwide

#16. Weston County

- 2010 to 2020 population change: -370
--- #2,003 among all counties nationwide
- 2010 to 2020 percent population change: -5.1%
--- #19 among counties in Wyoming, #2,349 among all counties nationwide
- 2020 population: 6,838
--- #21 largest county in Wyoming, #2,670 largest county nationwide

#15. Hot Springs County

- 2010 to 2020 population change: -191
--- #1,756 among all counties nationwide
- 2010 to 2020 percent population change: -4.0%
--- #18 among counties in Wyoming, #2,160 among all counties nationwide
- 2020 population: 4,621
--- #22 largest county in Wyoming, #2,845 largest county nationwide

#14. Big Horn County

- 2010 to 2020 population change: -147
--- #1,693 among all counties nationwide
- 2010 to 2020 percent population change: -1.3%
--- #13 among counties in Wyoming, #1,699 among all counties nationwide
- 2020 population: 11,521
--- #15 largest county in Wyoming, #2,314 largest county nationwide

#13. Johnson County

- 2010 to 2020 population change: -122
--- #1,656 among all counties nationwide
- 2010 to 2020 percent population change: -1.4%
--- #14 among counties in Wyoming, #1,733 among all counties nationwide
- 2020 population: 8,447
--- #18 largest county in Wyoming, #2,538 largest county nationwide

#12. Converse County

- 2010 to 2020 population change: -82
--- #1,602 among all counties nationwide
- 2010 to 2020 percent population change: -0.6%
--- #10 among counties in Wyoming, #1,583 among all counties nationwide
- 2020 population: 13,751
--- #13 largest county in Wyoming, #2,171 largest county nationwide

#11. Platte County

- 2010 to 2020 population change: -62
--- #1,578 among all counties nationwide
- 2010 to 2020 percent population change: -0.7%
--- #12 among counties in Wyoming, #1,597 among all counties nationwide
- 2020 population: 8,605
--- #17 largest county in Wyoming, #2,524 largest county nationwide

#10. Niobrara County

- 2010 to 2020 population change: -17
--- #1,511 among all counties nationwide
- 2010 to 2020 percent population change: -0.7%
--- #11 among counties in Wyoming, #1,593 among all counties nationwide
- 2020 population: 2,467
--- #23 largest county in Wyoming, #3,001 largest county nationwide

#9. Crook County

- 2010 to 2020 population change: +98
--- #1,398 among all counties nationwide
- 2010 to 2020 percent population change: +1.4%
--- #9 among counties in Wyoming, #1,268 among all counties nationwide
- 2020 population: 7,181
--- #20 largest county in Wyoming, #2,645 largest county nationwide

#8. Albany County

- 2010 to 2020 population change: +767
--- #1,067 among all counties nationwide
- 2010 to 2020 percent population change: +2.1%
--- #7 among counties in Wyoming, #1,164 among all counties nationwide
- 2020 population: 37,066
--- #6 largest county in Wyoming, #1,249 largest county nationwide

#7. Campbell County

- 2010 to 2020 population change: +893
--- #1,031 among all counties nationwide
- 2010 to 2020 percent population change: +1.9%
--- #8 among counties in Wyoming, #1,196 among all counties nationwide
- 2020 population: 47,026
--- #3 largest county in Wyoming, #1,035 largest county nationwide

#6. Park County

- 2010 to 2020 population change: +1,419
--- #919 among all counties nationwide
- 2010 to 2020 percent population change: +5.0%
--- #6 among counties in Wyoming, #819 among all counties nationwide
- 2020 population: 29,624
--- #8 largest county in Wyoming, #1,439 largest county nationwide

#5. Lincoln County

- 2010 to 2020 population change: +1,475
--- #909 among all counties nationwide
- 2010 to 2020 percent population change: +8.1%
--- #3 among counties in Wyoming, #559 among all counties nationwide
- 2020 population: 19,581
--- #11 largest county in Wyoming, #1,841 largest county nationwide

#4. Sheridan County

- 2010 to 2020 population change: +1,805
--- #844 among all counties nationwide
- 2010 to 2020 percent population change: +6.2%
--- #4 among counties in Wyoming, #685 among all counties nationwide
- 2020 population: 30,921
--- #7 largest county in Wyoming, #1,407 largest county nationwide

#3. Teton County

- 2010 to 2020 population change: +2,037
--- #810 among all counties nationwide
- 2010 to 2020 percent population change: +9.6%
--- #1 among counties in Wyoming, #447 among all counties nationwide
- 2020 population: 23,331
--- #9 largest county in Wyoming, #1,668 largest county nationwide

#2. Natrona County

- 2010 to 2020 population change: +4,505
--- #594 among all counties nationwide
- 2010 to 2020 percent population change: +6.0%
--- #5 among counties in Wyoming, #723 among all counties nationwide
- 2020 population: 79,955
--- #2 largest county in Wyoming, #712 largest county nationwide

#1. Laramie County

- 2010 to 2020 population change: +8,774
--- #455 among all counties nationwide
- 2010 to 2020 percent population change: +9.6%
--- #2 among counties in Wyoming, #448 among all counties nationwide
- 2020 population: 100,512
--- #1 largest county in Wyoming, #601 largest county nationwide