Fort Collins population
Fort Collins, Colorado had an estimated 171,500 residents on July 1, 2025, the 160th-largest city in the US. That is up 19.1% since the 2010 Census and up 41% since 2000.
- Population, July 2025
- 171,500+1% since April 2020
- People per sq mile
- 2,99657.2 sq mi of land
- Median age
- 30.912.8% are 65 or older
- Households with kids
- 22.5%with anyone under 18
Population by year, 2000 to 2025
| Year | Population | Change | Basis |
|---|---|---|---|
| 2025 | 171,500 | +773 | Estimate, July 1 |
| 2024 | 170,727 | +182 | Estimate, July 1 |
| 2023 | 170,545 | +288 | Estimate, July 1 |
| 2022 | 170,257 | +954 | Estimate, July 1 |
| 2021 | 169,303 | -477 | Estimate, July 1 |
| 2020 | 169,780 | +1,723 | April 2020 estimates base |
| 2019 | 168,057 | +1,656 | Estimate, July 1 |
| 2018 | 166,401 | +1,821 | Estimate, July 1 |
| 2017 | 164,580 | +1,851 | Estimate, July 1 |
| 2016 | 162,729 | +1,769 | Estimate, July 1 |
| 2015 | 160,960 | +4,945 | Estimate, July 1 |
| 2014 | 156,015 | +4,246 | Estimate, July 1 |
| 2013 | 151,769 | +2,195 | Estimate, July 1 |
| 2012 | 149,574 | +2,223 | Estimate, July 1 |
| 2011 | 147,351 | +3,365 | Estimate, July 1 |
| 2010 | 143,986 | +1,357 | 2010 Census (April 1) |
| 2009 | 142,629 | +2,345 | Estimate, July 1 |
| 2008 | 140,284 | +2,579 | Estimate, July 1 |
| 2007 | 137,705 | +2,515 | Estimate, July 1 |
| 2006 | 135,190 | +2,608 | Estimate, July 1 |
| 2005 | 132,582 | +1,669 | Estimate, July 1 |
| 2004 | 130,913 | +1,416 | Estimate, July 1 |
| 2003 | 129,497 | +1,425 | Estimate, July 1 |
| 2002 | 128,072 | +2,251 | Estimate, July 1 |
| 2001 | 125,821 | +4,230 | Estimate, July 1 |
| 2000 | 121,591 | April 2000 estimates base |
Year-to-year changes across 2010 and 2020 mix census counts with estimates, so small jumps at those years are partly method changes.
Frequently asked questions
What is the population of Fort Collins in 2025?
The Census Bureau estimates Fort Collins had 171,500 residents on July 1, 2025, making it the 160th-largest city in the US.
Is Fort Collins growing?
Yes. Fort Collins has grown 19.1% since the 2010 Census (143,986 people), and grown 1% since 2020.
What was the population of Fort Collins in 2000?
About 121,591 (the Census Bureau's April 2000 estimates base). By the 2010 Census it was 143,986.
How dense is Fort Collins?
Fort Collins has about 2,996 people per square mile of land (57.2 square miles).
More about Fort Collins
See cost of living, jobs and commutes in Fort Collins, Fort Collins weather by month, or every Fort Collins ZIP code. For the biggest cities in the country, see the largest US cities.