| 1512.5 | 1507.6 | 32 | 32 | Koutsouvelis, M (Matthew) | | ENM | 1707.6 | 1707.6 | South African Junior Closed Chess Championship 2026 (U12 Open) | 8 | 2026-04-01 | S | W | 0 | 0.31 | -0.31 | -10.1 | 0.31 | -0.31 | -9.9 |
| 1425.9 | 1419.7 | 20 | 20 | Koutsouvelis, M (Matthew) | | ENM | 1496.9 | 1497.3 | Ty's Winter Classic 2025 | 1 | 2025-06-27 | S | B | 0 | 0.38 | -0.38 | -6.3 | 0.37 | -0.37 | -7.4 |
| 1425.9 | 1419.7 | 20 | 20 | Koutsouvelis, M (Matthew) | | ENM | 1496.9 | 1497.3 | NMBCU Closed 2025 (U12) | 3 | 2025-06-14 | S | W | 0 | 0.46 | -0.46 | -7.6 | 0.45 | -0.45 | -9 |
| 1425.1 | 1419.7 | 20 | 20 | Koutsouvelis, M (Matthew) | | ENM | 1390 | 1372.3 | NMBCH Trial 1 2025 (U12) | 4 | 2025-02-15 | S | W | 0 | 0.58 | -0.58 | -9.6 | 0.6 | -0.6 | -12 |
| 1360.5 | 1377.8 | 20 | 20 | Koutsouvelis, M (Matthew) | | ENM | 1273.9 | 1320.3 | Eastern Cape Provincial Individual Championship 2023 (U10 Boys) | 7 | 2023-10-05 | S | B | 1 | 0.56 | 0.44 | 7.5 | 0.53 | 0.47 | 9.4 |
| 1236.2 | 1270.7 | 20 | 20 | Koutsouvelis, M (Matthew) | | ENM | 1200 | 1200 | NMB 1st Trials 2023 (U8+U10) | 1 | 2023-02-17 | S | B | 1 | 0.5 | 0.5 | 8.3 | 0.54 | 0.46 | 9.2 |
