| | Monte Sereno, CA | Loyola, CA | United States |
| Population | 3,502 | 3,564 | 329,725,481 |
| Female Population | 49.1% | 50.4% | 50.5% |
| Male Population | 50.9% | 49.6% | 49.5% |
| Median Age | 51.1 | 46.6 | 38.4 |
| space3 | | | |
| Population - 2010 | 3,337 | 3,316 | 309,327,143 |
| Population - 2000 | 3,483 | 3,478 | 285,036,114 |
| Population - 1990 | 3,287 | 3,076 | 251,960,433 |
| Pop. 2000 to Now | 0.2% | -1.3% | 15.6% |
| Pop. 1990 to Now | 6.2% | 11.6% | 30.8% |
| space4 | | | |
| Population Density | 2,157.7 | 2,499.3 | 93.4 |
| Land Area | 1.6 | 1.4 | 3,531,905.4 |
| Water Area | 0.0 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Monte Sereno, CA | Loyola, CA | United States |
| Age 0 to 4 | 1.8% | 4.5% | 5.9% |
| Age 5 to 9 | 6.8% | 10.2% | 6.1% |
| Age 10 to 14 | 8.9% | 11.6% | 6.6% |
| Age 15 to 17 | 5.5% | 3.9% | 3.9% |
| Age 18 to 20 | 2.9% | 1.0% | 4.0% |
| Age 21 to 24 | 2.7% | 0.9% | 5.2% |
| Age 25 to 34 | 3.1% | 5.6% | 13.8% |
| Age 35 to 44 | 8.9% | 10.1% | 12.9% |
| Age 45 to 54 | 14.4% | 17.3% | 12.6% |
| Age 55 to 59 | 10.7% | 7.3% | 6.7% |
| Age 60 to 64 | 8.9% | 4.6% | 6.3% |
| Age 65 to 74 | 13.2% | 15.1% | 9.6% |
| Age 75 to 84 | 8.7% | 5.2% | 4.5% |
| Age 85 and over | 3.3% | 2.8% | 1.9% |
| space1 | | | |
| Race | | | |
| | Monte Sereno, CA | Loyola, CA | United States |
| White | 70.2% | 57.5% | 59.4% |
| Black | 0.7% | 1.2% | 12.2% |
| Asian | 18.8% | 29.0% | 5.6% |
| Native American | 0.0% | 0.0% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.0% | 0.3% | 0.4% |
| Two or More Races | 2.2% | 7.2% | 3.2% |
| Hispanic | 8.0% | 4.8% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Monte Sereno, CA | Loyola, CA | United States |
| Married Population | 64.8% | 78.8% | 49.8% |
| Currently Married | 64.3% | 78.2% | 48.0% |
| Married but Separated | 0.5% | 0.6% | 1.8% |
| Single Population | 35.2% | 21.2% | 50.2% |
| Never Married | 22.7% | 11.8% | 33.8% |
| Divorced | 3.1% | 4.9% | 10.8% |
| Widowed | 9.4% | 4.5% | 5.6% |
| space5 | | | |
| Household Size | 2.87 | 2.96 | 2.60 |
| Households | 1,219 | 1,206 | 124,010,992 |
| Family Households | 1,010 | 1,037 | 80,755,759 |
| Married couple, w/children | 32.2% | 40.8% | 30.5% |
| Married couple, no children | 57.1% | 49.0% | 42.9% |
| Non Family Households | 209 | 169 | 43,255,233 |
| Single householder, w/children | 2.3% | 8.7% | 15.8% |
| Single householder, no children | 8.4% | 1.5% | 10.8% |