Roundup is a city located in Montana. With a 2020 population of 1,861, it is the 40th largest city in Montana and the 7890th largest city in the United States. Roundup is currently declining at a rate of -0.05% annually but its population has increased by 4.08% since the most recent census, which recorded a population of 1,788 in 2010. Roundup reached it's highest population of 1,893 in 2011. Spanning over 1 miles, Roundup has a population density of 1,439 people per square mile.
The average household income in Roundup is $42,492 with a poverty rate of 25.33%. The median rental costs in recent years comes to $736 per month, and the median house value is $104,000. The median age in Roundup is 39.4 years, 39.3 years for males, and 39.4 years for females. For every 100 females there are 92.1 males.