| | Oneonta, NY | Cortland, NY | United States |
| Population | 12,764 | 17,577 | 329,725,481 |
| Female Population | 52.3% | 53.6% | 50.5% |
| Male Population | 47.7% | 46.4% | 49.5% |
| Median Age | 21.9 | 27.1 | 38.4 |
| space3 | | | |
| Population - 2010 | 13,945 | 19,179 | 309,327,143 |
| Population - 2000 | 13,292 | 18,740 | 285,036,114 |
| Population - 1990 | 13,954 | 19,801 | 251,960,433 |
| Pop. 2000 to Now | 3.0% | -1.5% | 15.6% |
| Pop. 1990 to Now | -1.9% | -6.8% | 30.8% |
| space4 | | | |
| Population Density | 2,926.9 | 4,513.9 | 93.4 |
| Land Area | 4.4 | 3.9 | 3,531,905.4 |
| Water Area | 0.0 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Oneonta, NY | Cortland, NY | United States |
| Age 0 to 4 | 3.4% | 4.4% | 5.9% |
| Age 5 to 9 | 1.6% | 4.8% | 6.1% |
| Age 10 to 14 | 3.2% | 3.9% | 6.6% |
| Age 15 to 17 | 1.4% | 2.3% | 3.9% |
| Age 18 to 20 | 32.5% | 16.5% | 4.0% |
| Age 21 to 24 | 13.1% | 14.5% | 5.2% |
| Age 25 to 34 | 8.9% | 13.2% | 13.8% |
| Age 35 to 44 | 7.1% | 7.8% | 12.9% |
| Age 45 to 54 | 7.5% | 9.4% | 12.6% |
| Age 55 to 59 | 3.3% | 5.3% | 6.7% |
| Age 60 to 64 | 4.2% | 5.0% | 6.3% |
| Age 65 to 74 | 7.7% | 7.6% | 9.6% |
| Age 75 to 84 | 4.0% | 3.3% | 4.5% |
| Age 85 and over | 2.1% | 2.0% | 1.9% |
| space1 | | | |
| Race | | | |
| | Oneonta, NY | Cortland, NY | United States |
| White | 81.3% | 88.3% | 59.4% |
| Black | 5.0% | 3.4% | 12.2% |
| Asian | 2.7% | 1.0% | 5.6% |
| Native American | 0.1% | 0.0% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.4% | 0.2% | 0.4% |
| Two or More Races | 2.9% | 2.5% | 3.2% |
| Hispanic | 7.6% | 4.6% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Oneonta, NY | Cortland, NY | United States |
| Married Population | 23.3% | 29.0% | 49.8% |
| Currently Married | 22.2% | 26.6% | 48.0% |
| Married but Separated | 1.1% | 2.4% | 1.8% |
| Single Population | 76.7% | 71.0% | 50.2% |
| Never Married | 64.6% | 56.2% | 33.8% |
| Divorced | 8.1% | 10.5% | 10.8% |
| Widowed | 4.0% | 4.3% | 5.6% |
| space5 | | | |
| Household Size | 2.06 | 2.20 | 2.60 |
| Households | 3,935 | 6,588 | 124,010,992 |
| Family Households | 1,984 | 3,167 | 80,755,759 |
| Married couple, w/children | 21.1% | 24.7% | 30.5% |
| Married couple, no children | 44.2% | 36.9% | 42.9% |
| Non Family Households | 1,951 | 3,421 | 43,255,233 |
| Single householder, w/children | 21.0% | 28.1% | 15.8% |
| Single householder, no children | 13.8% | 10.3% | 10.8% |