| Statistic | Sarnia | Ontario | National |
| Population | 74,477 | 14,804,681 | 38,134,230 |
| Population density (sq km) | 449 | 15 | 4 |
| Median age | 45.8 | 40.9 | 40.9 |
| Male/Female ratio | 1.1:1 | 1.0:1 | 1.0:1 |
| Married couples | 68% | 71% | 66% |
| Families w/ kids at home | 36% | 46% | 43% |
| Speak English only | 91.9% | 86.1% | 68.8% |
| Speak French only | 0.1% | 0.3% | 4.5% |
| Data | Percent |
| South Asian | 2.1% |
| Black | 1.7% |
| Chinese | 0.9% |
| Arab | 0.7% |
| Latin American | 0.6% |
| Data | Percent |
| United Kingdom | 3.1% |
| United States | 1.4% |
| Italy | 0.8% |
| Netherlands | 0.8% |
| India | 0.7% |