- Salida (Population: 5,504)
- Security-Widefield (Population: 29,845)
- Sheridan (Population: 5,600)
- Sherrelwood (Population: 17,657)
- Silt (Population: 1,740)
- Silverthorne (Population: 3,196)
- Snowmass Village (Population: 1,822)
- Southglenn (Population: 43,520)
- Springfield (Population: 1,562)
- Steamboat Springs (Population: 9,815)
- Sterling (Population: 11,360)
- Stonegate (Population: 6,284)
- Strasburg (Population: 1,402)
- Stratmoor (Population: 6,650)
- Superior (Population: 9,011)
