| Statistic | Sainte-Marthe-sur-le-Lac | Montréal | Quebec |
| Population | 19,760 | 1,811,008 | 8,565,732 |
| Population density (sq km) | 2,309 | 4,984 | 6 |
| Median age | 38.1 | 38.7 | 42.6 |
| Male/Female ratio | 1.0:1 | 1.0:1 | 1.0:1 |
| Married couples | 46% | 54% | 50% |
| Families w/ kids at home | 49% | 41% | 40% |
| Speak English only | 1.2% | 10.2% | 4.7% |
| Speak French only | 49.1% | 29.8% | 49.5% |
| Data | Percent |
| Black | 3.2% |
| Arab | 2.1% |
| Latin American | 1.1% |
| Southeast Asian | 0.6% |
| Chinese | 0.4% |
| Data | Percent |
| France | 0.9% |
| Morocco | 0.8% |
| Other Western Africa | 0.5% |
| Algeria | 0.5% |
| Romania | 0.5% |