Gillette is a city located in Campbell County Wyoming. It is also the county seat of Campbell County. With a 2020 population of 31,978, it is the 4th largest city in Wyoming (after Cheyenne, , and ) and the 1227th largest city in the United States . Gillette is currently declining at a rate of -0.08% annually but its population has increased by 9.94% since the most recent census, which recorded a population of 29,087 in 2010. Gillette reached it's highest population of in . Spanning over 23 miles, Gillette has a population density of 1,391 people per square mile.
The average household income in Gillette is $87,739 with a poverty rate of 14.28%. The median rental costs in recent years comes to $898 per month, and the median house value is $216,400. The median age in Gillette is 31.4 years, 31.4 years for males, and 31.5 years for females.