| | Iowa Falls, IA | Eldora, IA | United States |
| Population | 5,154 | 2,673 | 329,725,481 |
| Female Population | 46.3% | 49.6% | 50.5% |
| Male Population | 53.7% | 50.4% | 49.5% |
| Median Age | 41.6 | 40 | 38.4 |
| space3 | | | |
| Population - 2010 | 5,283 | 2,731 | 309,327,143 |
| Population - 2000 | 5,193 | 3,035 | 285,036,114 |
| Population - 1990 | 5,424 | 3,038 | 251,960,433 |
| Pop. 2000 to Now | -4.9% | -15.3% | 15.6% |
| Pop. 1990 to Now | -8.9% | -15.4% | 30.8% |
| space4 | | | |
| Population Density | 958.2 | 624.4 | 93.4 |
| Land Area | 5.4 | 4.3 | 3,531,905.4 |
| Water Area | 0.1 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Iowa Falls, IA | Eldora, IA | United States |
| Age 0 to 4 | 4.7% | 3.3% | 5.9% |
| Age 5 to 9 | 5.3% | 5.4% | 6.1% |
| Age 10 to 14 | 4.4% | 3.7% | 6.6% |
| Age 15 to 17 | 2.3% | 11.9% | 3.9% |
| Age 18 to 20 | 7.4% | 2.2% | 4.0% |
| Age 21 to 24 | 7.2% | 3.7% | 5.2% |
| Age 25 to 34 | 12.2% | 12.0% | 13.8% |
| Age 35 to 44 | 9.2% | 13.6% | 12.9% |
| Age 45 to 54 | 10.2% | 11.5% | 12.6% |
| Age 55 to 59 | 6.7% | 5.4% | 6.7% |
| Age 60 to 64 | 7.3% | 7.8% | 6.3% |
| Age 65 to 74 | 11.1% | 10.0% | 9.6% |
| Age 75 to 84 | 6.1% | 6.4% | 4.5% |
| Age 85 and over | 5.9% | 3.2% | 1.9% |
| space1 | | | |
| Race | | | |
| | Iowa Falls, IA | Eldora, IA | United States |
| White | 93.6% | 80.6% | 59.4% |
| Black | 0.6% | 4.2% | 12.2% |
| Asian | 0.0% | 3.3% | 5.6% |
| Native American | 0.0% | 5.9% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.1% | 0.0% | 0.4% |
| Two or More Races | 0.8% | 3.4% | 3.2% |
| Hispanic | 4.9% | 2.7% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Iowa Falls, IA | Eldora, IA | United States |
| Married Population | 52.6% | 43.4% | 49.8% |
| Currently Married | 52.4% | 42.3% | 48.0% |
| Married but Separated | 0.2% | 1.1% | 1.8% |
| Single Population | 47.4% | 56.6% | 50.2% |
| Never Married | 31.2% | 34.2% | 33.8% |
| Divorced | 8.1% | 14.7% | 10.8% |
| Widowed | 8.1% | 7.6% | 5.6% |
| space5 | | | |
| Household Size | 2.15 | 2.35 | 2.60 |
| Households | 2,216 | 1,013 | 124,010,992 |
| Family Households | 1,211 | 631 | 80,755,759 |
| Married couple, w/children | 23.7% | 35.5% | 30.5% |
| Married couple, no children | 58.9% | 38.7% | 42.9% |
| Non Family Households | 1,005 | 382 | 43,255,233 |
| Single householder, w/children | 13.0% | 19.0% | 15.8% |
| Single householder, no children | 4.4% | 6.8% | 10.8% |