| | Greenville, RI | Smithfield, RI | United States |
| Population | 8,955 | 21,855 | 329,725,481 |
| Female Population | 52.8% | 52.1% | 50.5% |
| Male Population | 47.3% | 47.9% | 49.5% |
| Median Age | 51.4 | 44.5 | 38.4 |
| space3 | | | |
| Population - 2010 | 8,767 | 21,400 | 309,327,143 |
| Population - 2000 | 8,626 | 20,613 | 285,036,114 |
| Population - 1990 | 8,303 | 19,163 | 251,960,433 |
| Pop. 2000 to Now | -2.4% | 6.0% | 15.6% |
| Pop. 1990 to Now | 1.4% | 14.0% | 30.8% |
| space4 | | | |
| Population Density | 1,755.9 | 830.8 | 93.4 |
| Land Area | 5.1 | 26.3 | 3,531,905.4 |
| Water Area | 0.6 | 1.5 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Greenville, RI | Smithfield, RI | United States |
| Age 0 to 4 | 2.8% | 2.7% | 5.9% |
| Age 5 to 9 | 3.6% | 3.6% | 6.1% |
| Age 10 to 14 | 5.1% | 5.1% | 6.6% |
| Age 15 to 17 | 4.2% | 4.2% | 3.9% |
| Age 18 to 20 | 4.0% | 13.2% | 4.0% |
| Age 21 to 24 | 3.7% | 4.9% | 5.2% |
| Age 25 to 34 | 10.3% | 9.4% | 13.8% |
| Age 35 to 44 | 8.5% | 7.4% | 12.9% |
| Age 45 to 54 | 12.4% | 14.3% | 12.6% |
| Age 55 to 59 | 7.1% | 6.3% | 6.7% |
| Age 60 to 64 | 7.6% | 6.8% | 6.3% |
| Age 65 to 74 | 11.7% | 11.0% | 9.6% |
| Age 75 to 84 | 13.4% | 8.2% | 4.5% |
| Age 85 and over | 5.8% | 2.9% | 1.9% |
| space1 | | | |
| Race | | | |
| | Greenville, RI | Smithfield, RI | United States |
| White | 92.1% | 88.5% | 59.4% |
| Black | 0.8% | 1.2% | 12.2% |
| Asian | 1.0% | 3.0% | 5.6% |
| Native American | 0.0% | 0.1% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.1% | 0.1% | 0.4% |
| Two or More Races | 1.6% | 2.0% | 3.2% |
| Hispanic | 4.4% | 5.2% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Greenville, RI | Smithfield, RI | United States |
| Married Population | 51.8% | 45.7% | 49.8% |
| Currently Married | 51.6% | 45.3% | 48.0% |
| Married but Separated | 0.2% | 0.4% | 1.8% |
| Single Population | 48.2% | 54.3% | 50.2% |
| Never Married | 28.2% | 39.4% | 33.8% |
| Divorced | 8.3% | 7.6% | 10.8% |
| Widowed | 11.7% | 7.3% | 5.6% |
| space5 | | | |
| Household Size | 2.32 | 2.35 | 2.60 |
| Households | 3,634 | 7,828 | 124,010,992 |
| Family Households | 2,295 | 4,855 | 80,755,759 |
| Married couple, w/children | 28.2% | 30.7% | 30.5% |
| Married couple, no children | 58.2% | 56.4% | 42.9% |
| Non Family Households | 1,339 | 2,973 | 43,255,233 |
| Single householder, w/children | 7.5% | 7.0% | 15.8% |
| Single householder, no children | 6.0% | 5.9% | 10.8% |