O'Leary's 2026 population is now estimated at 2,935. In 2001, the population of O'Leary was 2,811. O'Leary has grown by 57 in the last year, which represents a 1.98% annual change. These population values and projections come from Statistics Canada Table 17-10-0155-01: Population estimates, July 1, by census subdivision, 2021 boundaries and World Population Review Internal Projections .
| City | 2026 Pop. ↓ | Growth |
|---|---|---|
| Toronto | 3,358,275 | 2.64% |
| Montreal | 1,943,903 | 1.49% |
| Calgary | 1,678,073 | 4.04% |
| Edmonton | 1,284,480 | 3.73% |
| Ottawa | 1,218,903 | 2.59% |
| Winnipeg | 870,032 | 2.33% |
| Brampton | 801,732 | 3.08% |
| Mississauga | 768,794 | 0.55% |
| Vancouver | 751,644 | 1.51% |
| Surrey | 731,630 | 3.99% |
| Hamilton | 652,266 | 1.84% |
| Quebec | 602,025 | 1.58% |
| Halifax | 532,856 | 3.1% |
| London | 508,883 | 2.85% |
| Laval | 466,247 | 1.03% |
| Markham | 376,096 | 1.24% |
| Vaughan | 364,031 | 1.53% |
| Kitchener | 338,883 | 4.62% |
| Saskatoon | 328,613 | 3.32% |
| Burnaby | 309,694 | 3.34% |