| Statistic | L'Islet | Quebec | National |
| Population | 3,712 | 8,565,732 | 38,134,230 |
| Population density (sq km) | 32 | 6 | 4 |
| Median age | 51.2 | 42.6 | 40.9 |
| Male/Female ratio | 1.0:1 | 1.0:1 | 1.0:1 |
| Married couples | 47% | 50% | 66% |
| Families w/ kids at home | 36% | 40% | 43% |
| Speak English only | 0.0% | 4.7% | 68.8% |
| Speak French only | 85.0% | 49.5% | 4.5% |
| Data | Percent |
| Latin American | 0.1% |
| Korean | 0.1% |
| N/A | 0.0% |
| Data | Percent |
| Haiti | 0.2% |
| Colombia | 0.2% |
| Italy | 0.1% |
| Germany | 0.1% |
| France | 0.1% |