| Statistic | Saint-Thomas | Joliette | Quebec |
| Population | 3,645 | 21,376 | 8,565,732 |
| Population density (sq km) | 39 | 913 | 6 |
| Median age | 42.9 | 46.3 | 42.6 |
| Male/Female ratio | 1.0:1 | 1.1:1 | 1.0:1 |
| Married couples | 48% | 40% | 50% |
| Families w/ kids at home | 39% | 31% | 40% |
| Speak English only | 0.1% | 0.2% | 4.7% |
| Speak French only | 78.6% | 69.6% | 49.5% |
| Data | Percent |
| Black | 0.8% |
| West Asian | 0.3% |
| Southeast Asian | 0.3% |
| Arab | 0.1% |
| Korean | 0.0% |
| Data | Percent |
| Haiti | 0.3% |
| France | 0.2% |
| Italy | 0.2% |
| Iran | 0.1% |
| Other Western Europe | 0.1% |