Fort Collins Colorado Population 2024 Population. The population of fort collins is 166,069, with a population density of 2,902 people per square mile, diverging from the national average of 91. This figure is an estimate and may slightly change as people get born.

According to the state demographer’s office, as of november 2023, there were 171,848 residents. The population of fort collins is 166,069, with a population density of 2,902 people per square mile, diverging from the national average of 91.