This is the SACE Honour Roll, listing every award, merit or prize won by South Australian SACE students in 2021, along with their school and subject details.
The report also includes significant Australian national awards and prizes such as the Australian Student Prize.
| 833 | O'Callaghan, Lauren Grace | SA | Merit | English Literary Studies | |
| 834 | O'Connell, Grainne Anneke | SA | Merit | Psychology | |
| 835 | O'Connor, Ella Mary Maeve | SA | Merit | Biology | |
| 836 | O'Connor, Ella Mary Maeve | SA | Merit | Nutrition | |
| 837 | O'Dwyer, Paige | SA | Merit | Integrated Learning A | |
| 838 | O'Reardon, Harriet | SA | Merit | Child Studies | |
| 839 | O'Reardon, Harriet | SA | Merit | Society and Culture | |
| 840 | O'Rielly, Tahlia | SA | Merit | Dance | |
| 841 | O'Shannessy, Riley | SA | Merit | Research Project B | |
| 842 | Oberdan, Dana Gina | SA | Merit | Chemistry | |
| |
|||||
| 843 | Oberdan, Dana Gina | SA | Merit | English | |
| 844 | Oehler, Josephine | SA | Merit | Chemistry | |
| 845 | Oehler, Josephine | SA | Merit | English | |
| 846 | Olafsen, Samuel | SA | Merit | General Mathematics | |
| 847 | Oldfield, Thomas James | SA | Merit | English | |
| 848 | Olijnyk, Marina | SA | Merit | Music Performance - Solo | |
| 849 | Ong, Gavin Michael | SA | Merit | Research Project B | |
| 850 | Ong, Leon Chong Shin | SA | Merit | Outdoor Education | |
| 851 | Organ, Caitlin Rose | SA | Merit | Psychology | |
| 852 | Orsillo, Lillian | SA | Merit | Legal Studies | |
| 853 | Orsillo, Lillian | Sacred Heart College | Somerton Park | Gov of SA SACE Award | |
| 854 | Otsuka, Hinako | SA | Merit | Japanese (Continuers) | |
| 855 | Ouyang, Sihui | SA | Merit | Food and Hospitality | |
| 856 | Owen, Braden Phillip | SA | Merit | Research Project B | |
| 857 | Oxford, Hannah Rose Marie | SA | Merit | Society and Culture | |
| 858 | Oxlad, Ryan David | SA | Merit | Industry and Entrepreneurial Solutions | |
| 859 | Oxlad, Ryan David | SA | Merit | Research Project B | |
| 860 | Page, Nikita | Wilderness School | Medindie | Gov of SA SACE Award | |
| 861 | Page, Nikita Lillian | SA | Merit | Mathematical Methods | |
| 862 | Page, Nikita Lillian | SA | Merit | Specialist Mathematics | |
| 863 | Pannu, Mansher Singh | SA | Merit | Research Project B | |
| 864 | Pant, Aashna | SA | Merit | General Mathematics | |
| 865 | Papageorgiou, Vasili | SA | Merit | Research Project B | |
| 866 | Paramasivam, Sahithya | SA | Merit | Research Project B | |
| 867 | Paranavithana, Rajiv | SA | Merit | Mathematical Methods | |
| 868 | Parhas, Panae | SA | Merit | Physical Education | |
| 869 | Park, Gyum | SA | Merit | Chemistry | |
| 870 | Park, Gyum | SA | Merit | Physics | |
| 871 | Park, Gyum | SA | Merit | Research Project B | |
| 872 | Park, Gyum (Clive) | Pembroke School | Kensington Park | Gov of SA SACE Award | |
| 873 | Park, Sean | SA | Merit | Integrated Learning A | |
| 874 | Parker, Amelie Cate | SA | Merit | Research Project B | |
| 875 | Partridge, Joshua | SA | Merit | Media Studies | |
| 876 | Partridge, Joshua | SA | Merit | Society and Culture | |
| 877 | Pascual, Ma Izabelle Paresh | SA | Merit | English | |
| 878 | Patel, Aashvi | SA | Merit | Biology | |
| 879 | Patel, Aashvi | SA | Merit | General Mathematics | |
| 880 | Patel, Hriday | SA | Merit | Chemistry | |
| 881 | Patel, Hriday | SA | Merit | Specialist Mathematics | |
| 882 | Patel, Keya | SA | Merit | Mathematical Methods | |