| | Spring Lake, FL | Big Pine Key, FL | United States |
| Population | 469 | 4,752 | 329,725,481 |
| Female Population | 52.5% | 47.2% | 50.5% |
| Male Population | 47.6% | 52.8% | 49.5% |
| Median Age | 54.1 | 52.1 | 38.4 |
| space3 | | | |
| Population - 2010 | 480 | 3,747 | 309,327,143 |
| Population - 2000 | 327 | 5,032 | 285,036,114 |
| Population - 1990 | 313 | 4,206 | 251,960,433 |
| Pop. 2000 to Now | 84.7% | 2.2% | 15.6% |
| Pop. 1990 to Now | 93.0% | 22.2% | 30.8% |
| space4 | | | |
| Population Density | 140.8 | 465.7 | 93.4 |
| Land Area | 3.3 | 10.2 | 3,531,905.4 |
| Water Area | 0.1 | 0.1 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Spring Lake, FL | Big Pine Key, FL | United States |
| Age 0 to 4 | 0.0% | 5.5% | 5.9% |
| Age 5 to 9 | 3.4% | 5.4% | 6.1% |
| Age 10 to 14 | 6.6% | 4.6% | 6.6% |
| Age 15 to 17 | 0.0% | 2.0% | 3.9% |
| Age 18 to 20 | 3.2% | 0.7% | 4.0% |
| Age 21 to 24 | 5.3% | 4.5% | 5.2% |
| Age 25 to 34 | 2.8% | 8.6% | 13.8% |
| Age 35 to 44 | 11.1% | 13.0% | 12.9% |
| Age 45 to 54 | 22.0% | 10.6% | 12.6% |
| Age 55 to 59 | 9.2% | 10.9% | 6.7% |
| Age 60 to 64 | 0.0% | 10.9% | 6.3% |
| Age 65 to 74 | 30.3% | 15.7% | 9.6% |
| Age 75 to 84 | 6.2% | 6.6% | 4.5% |
| Age 85 and over | 0.0% | 1.1% | 1.9% |
| space1 | | | |
| Race | | | |
| | Spring Lake, FL | Big Pine Key, FL | United States |
| White | 81.2% | 79.4% | 59.4% |
| Black | 0.0% | 0.5% | 12.2% |
| Asian | 0.0% | 0.8% | 5.6% |
| Native American | 0.0% | 0.0% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.0% | 0.0% | 0.4% |
| Two or More Races | 0.0% | 1.5% | 3.2% |
| Hispanic | 18.8% | 17.8% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Spring Lake, FL | Big Pine Key, FL | United States |
| Married Population | 65.4% | 54.9% | 49.8% |
| Currently Married | 64.2% | 53.7% | 48.0% |
| Married but Separated | 1.2% | 1.2% | 1.8% |
| Single Population | 34.6% | 45.1% | 50.2% |
| Never Married | 16.1% | 22.7% | 33.8% |
| Divorced | 18.5% | 15.2% | 10.8% |
| Widowed | 0.0% | 7.2% | 5.6% |
| space5 | | | |
| Household Size | 2.58 | 2.50 | 2.60 |
| Households | 182 | 1,873 | 124,010,992 |
| Family Households | 172 | 1,193 | 80,755,759 |
| Married couple, w/children | 11.0% | 23.6% | 30.5% |
| Married couple, no children | 64.5% | 57.5% | 42.9% |
| Non Family Households | 10 | 680 | 43,255,233 |
| Single householder, w/children | 6.4% | 12.7% | 15.8% |
| Single householder, no children | 18.0% | 6.2% | 10.8% |