| | Montpelier, OH | Bryan, OH | United States |
| Population | 3,947 | 8,668 | 329,725,481 |
| Female Population | 49.9% | 51.9% | 50.5% |
| Male Population | 50.1% | 48.1% | 49.5% |
| Median Age | 38.4 | 42.5 | 38.4 |
| space3 | | | |
| Population - 2010 | 4,053 | 8,411 | 309,327,143 |
| Population - 2000 | 4,320 | 8,333 | 285,036,114 |
| Population - 1990 | 4,299 | 8,348 | 251,960,433 |
| Pop. 2000 to Now | -9.6% | -1.5% | 15.6% |
| Pop. 1990 to Now | -9.1% | -1.6% | 30.8% |
| space4 | | | |
| Population Density | 1,362.9 | 1,609.4 | 93.4 |
| Land Area | 2.9 | 5.4 | 3,531,905.4 |
| Water Area | 0.0 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Montpelier, OH | Bryan, OH | United States |
| Age 0 to 4 | 8.8% | 4.2% | 5.9% |
| Age 5 to 9 | 7.8% | 4.9% | 6.1% |
| Age 10 to 14 | 3.2% | 6.7% | 6.6% |
| Age 15 to 17 | 4.4% | 4.2% | 3.9% |
| Age 18 to 20 | 1.9% | 2.5% | 4.0% |
| Age 21 to 24 | 6.9% | 4.5% | 5.2% |
| Age 25 to 34 | 14.7% | 14.4% | 13.8% |
| Age 35 to 44 | 10.2% | 12.2% | 12.9% |
| Age 45 to 54 | 10.1% | 10.8% | 12.6% |
| Age 55 to 59 | 8.0% | 6.8% | 6.7% |
| Age 60 to 64 | 5.9% | 6.7% | 6.3% |
| Age 65 to 74 | 8.5% | 13.1% | 9.6% |
| Age 75 to 84 | 6.3% | 5.4% | 4.5% |
| Age 85 and over | 3.4% | 3.7% | 1.9% |
| space1 | | | |
| Race | | | |
| | Montpelier, OH | Bryan, OH | United States |
| White | 91.6% | 94.0% | 59.4% |
| Black | 0.8% | 1.3% | 12.2% |
| Asian | 0.4% | 0.6% | 5.6% |
| Native American | 0.3% | 0.1% | 0.6% |
| Hawaiian, Pacific Islander | 0.0% | 0.0% | 0.2% |
| Other | 0.0% | 0.0% | 0.4% |
| Two or More Races | 0.4% | 0.5% | 3.2% |
| Hispanic | 6.4% | 3.6% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Montpelier, OH | Bryan, OH | United States |
| Married Population | 42.0% | 37.2% | 49.8% |
| Currently Married | 39.7% | 36.9% | 48.0% |
| Married but Separated | 2.3% | 0.3% | 1.8% |
| Single Population | 58.0% | 62.8% | 50.2% |
| Never Married | 30.2% | 36.6% | 33.8% |
| Divorced | 16.6% | 16.9% | 10.8% |
| Widowed | 11.3% | 9.2% | 5.6% |
| space5 | | | |
| Household Size | 2.14 | 2.13 | 2.60 |
| Households | 1,816 | 4,024 | 124,010,992 |
| Family Households | 1,020 | 2,184 | 80,755,759 |
| Married couple, w/children | 25.0% | 25.4% | 30.5% |
| Married couple, no children | 36.2% | 34.5% | 42.9% |
| Non Family Households | 796 | 1,840 | 43,255,233 |
| Single householder, w/children | 25.7% | 22.9% | 15.8% |
| Single householder, no children | 13.1% | 17.2% | 10.8% |