| |
| Tartan Name | Ontario Provincial Police | | | | Category | Corporate
| Reference | 10019 | | Designer | Brown, David & Hall, Fiona | | | | Date Recorded | 23/04/2009 | | |
| |  |
| |
| Tartan Name | Ontario, Ensign of | | | | Category | District
| | | | Designer | Rotex Ltd | STA Ref | 3140 | | Date Recorded | Not Specified | STWR Ref | none |
| | |
| |
| Tartan Name | Ontario, Northern | | | | Category | District
| | | | Designer | Teall/Smith | STA Ref | 956 | | Date Recorded | Not Specified | STWR Ref | 956 |
| | |
| |
| Tartan Name | Ontex | | | | Category | Corporate
| Reference | 11358 | | Designer | McCann/Urquhart | | | | Date Recorded | 03/09/2015 | | |
| | |
| |
| Tartan Name | Ooni Limited | | | | Category | Corporate
| Reference | 13649 | | Designer | Prickly Thistle Scotland Ltd | | | | Date Recorded | 11/10/2022 | | |
| | |
| |
| |  |
| |
| Tartan Name | Open Championship (1998) | | | | Category | Corporate
| | | | Designer | House of Edgar - Macnaughton Holdings Ltd. | STA Ref | 2575 | | Date Recorded | Not Specified | STWR Ref | 2575 |
| | |
| |
| | |
| |
| Tartan Name | Open Championship, The | | | | Category | Corporate
| | | | Designer | Not Specified | STA Ref | none | | Date Recorded | Not Specified | STWR Ref | 2803 |
| | |
| |
| | |
| |
| Tartan Name | Operation Encompass | | | | Category | Corporate
| Reference | 11951 | | Designer | Wilton, Brian | | | | Date Recorded | 19/10/2017 | | |
| |  |
| |
| Tartan Name | Optica Quantum | | | | Category | Corporate
| Reference | 15434 | | Designer | Wilton, Brian | | | | Date Recorded | 02/06/2026 | | |
| | |
| |
| Tartan Name | Orange Fanaticos | | | | Category | Corporate
| Reference | 10105 | | Designer | Frankfort, David C | | | | Date Recorded | 23/11/2009 | | |
| |  |
| |
| Tartan Name | Oranje Veld | | | | Category | Fashion
| Reference | 15322 | | Designer | International Tartans | | | | Date Recorded | 16/03/2026 | | |
| | |
| |
| | |
| |
| | |
| |
| Tartan Name | Order of Saint Lazarus | | | | Category | Corporate
| Reference | 11388 | | Designer | Ross/Waterton-Anderson | | | | Date Recorded | 14/10/2015 | | |
| | |
| |
| | |
| |
| | |
| |
| Tartan Name | Order of the Holy Sepulchre | | | | Category | Corporate
| | | | Designer | Kinsey, Ronald Stuart | STA Ref | 2161 | | Date Recorded | Not Specified | STWR Ref | 2161 |
| | |