| Place | State | Latitude | Longitude | Elevation (meters) | Elevation (feet) |
|---|
| One Hundred Fifty Mile House | Province of British Columbia | 52.1166667 | -121.9333333 | 749 | 2457 |
| One Hundred Mile House | Province de Colombie-Britannique | 51.65 | -121.2833333 | 919 | 3015 |
| One Hundred Mile House | Province of British Columbia | 51.65 | -121.2833333 | 919 | 3015 |
| Onefour | Province of Alberta | 49.0666667 | -110.45 | 892 | 2927 |
| Onefour | Province d' Alberta | 49.0666667 | -110.45 | 892 | 2927 |
| Onion Lake | Province of Saskatchewan | 53.7166667 | -110 | 603 | 1978 |
| Onion Lake | Province de Saskatchewan | 53.7166667 | -110 | 603 | 1978 |
| Onoway | Province of Alberta | 53.7 | -114.1833333 | 710 | 2329 |
| Onoway | Province d' Alberta | 53.7 | -114.1833333 | 710 | 2329 |
| Oona River | Province de Colombie-Britannique | 53.95 | -130.25 | 56 | 184 |
| Oona River | Province of British Columbia | 53.95 | -130.25 | 56 | 184 |
| Ootischenia | Province de Colombie-Britannique | 49.2833333 | -117.6166667 | 549 | 1801 |
| Ootischenia | Province of British Columbia | 49.2833333 | -117.6166667 | 549 | 1801 |
| Ootsa Lake | Province de Colombie-Britannique | 53.7833333 | -126.0333333 | 848 | 2782 |
| Ootsa Lake | Province of British Columbia | 53.7833333 | -126.0333333 | 848 | 2782 |
| Opasatika | Province of Ontario | 49.5333333 | -82.8666667 | 225 | 738 |
| Opasatika | Province d' Ontario | 49.5333333 | -82.8666667 | 225 | 738 |
| Opasquia | Province of Ontario | 53.2666667 | -93.5666667 | 271 | 889 |
| Opasquia | Province d' Ontario | 53.2666667 | -93.5666667 | 271 | 889 |
| Open Hall | Province de Terre-Neuve-et-Labrador | 48.55 | -53.4833333 | 24 | 79 |
