| Jul 31, 2025 | Fellman | 1–0 | Hafthorsson | Jonkoping Chess Festival 2025 - Rapid Open | King's Indian Defense | |
| Jul 31, 2025 | Hafthorsson | 0–1 | Banerjee | Jonkoping Chess Festival 2025 - Rapid Open | Rapport-Jobava System | |
| Jul 31, 2025 | Hafthorsson | 1–0 | Hansson | Jonkoping Chess Festival 2025 - Rapid Open | Queen's Pawn Game: Chigorin Variation, Shaviliuk Gambit | |
| Jul 31, 2025 | Harila | ½–½ | Hafthorsson | Jonkoping Chess Festival 2025 - Standard Open | King's Indian Defense | |
| Jul 31, 2025 | Loay | 1–0 | Hafthorsson | Jonkoping Chess Festival 2025 - Blitz Open | Sicilian Defense | |
| Jul 31, 2025 | Ravik | 1–0 | Hafthorsson | Jonkoping Chess Festival 2025 - Blitz Open | Sicilian Defense: Accelerated Dragon, Maróczy Bind | |
| Jul 30, 2025 | Hafthorsson | 1–0 | Kullander | Jonkoping Chess Festival 2025 - Standard Open | Indian Defense | |
| Jul 29, 2025 | Zakrzewicz | ½–½ | Hafthorsson | Jonkoping Chess Festival 2025 - Standard Open | Sicilian Defense: Nyezhmetdinov-Rossolimo Attack, Fianchetto Variation | |
| Jul 28, 2025 | Berggren Torell | 1–0 | Hafthorsson | Jonkoping Chess Festival 2025 - Standard Open | King's Indian Attack: Symmetrical Defense | |
| Jul 28, 2025 | Hafthorsson | 0–1 | Josse | Jonkoping Chess Festival 2025 - Standard Open | Rapport-Jobava System, with e6 | |
| Jul 27, 2025 | Hafthorsson | 1–0 | Nielsen | Jonkoping Chess Festival 2025 - Standard Open | Pirc Defense: Classical Variation | |
| Jul 26, 2025 | Miskulin | ½–½ | Hafthorsson | Jonkoping Chess Festival 2025 - Standard Open | Sicilian Defense: Alapin Variation | |
| Apr 10, 2025 | Hafthorsson | 0–1 | Beisteiner | Reykjavik Open 2025 | Rapport-Jobava System | |
| Oct 30, 2024 | Lindberg Hansen | 0–1 | Hafthorsson | Round 8: Lindberg Hansen, Noa - Hafthorsson, Jon Ulfur | Sicilian Defense: Accelerated Dragon, Maróczy Bind | |
| Aug 18, 2024 | Karkovic | 1–0 | Hafthorsson | Round 7: Karkovic, Mate - Hafthorsson, Jon Ulfur | Pirc Defense: Kholmov System | |
| Aug 17, 2024 | Hafthorsson | ½–½ | Strand | Round 6: Hafthorsson, Jon Ulfur - Strand, Sixten | Nimzo-Larsen Attack: Modern Variation | |
| Aug 16, 2024 | Agren | 0–1 | Hafthorsson | Round 5: Agren, Elvis - Hafthorsson, Jon Ulfur | King's Indian Defense: Normal Variation, King's Knight Variation | |
| Aug 15, 2024 | Hafthorsson | 1–0 | Petersson | Round 4: Hafthorsson, Jon Ulfur - Petersson, Axel | Pirc Defense: Kholmov System | |
| Aug 13, 2024 | Hafthorsson | 0–1 | Deruelle Sala | Round 2: Hafthorsson, Jon Ulfur - Deruelle Sala, Albert | Horwitz Defense | |
| Aug 12, 2024 | Halldorsson | 0–1 | Hafthorsson | Round 1: Halldorsson,Thorsteinn Fridrik - Hafthorsson, Jon Ulfur | King's Indian Defense | |
| Aug 7, 2024 | Wedenberg | 1–0 | Hafthorsson | Round 3: Wedenberg, Oliver - Hafthorsson, Jon Ulfur | Italian Game: Classical Variation, Center Attack | |
| Mar 31, 2023 | Botez | 1–0 | Hafthorsson | Reykjavik Open | King's Indian Defense: Orthodox Variation | |
| Aug 14, 2022 | Wingh | 0–1 | Hafthorsson | Uppsala Open | Vienna Game: Vienna Gambit, Paulsen Attack | |
| Apr 7, 2022 | Hafthorsson | 0–1 | Natoli | Kvika Reykjavik Open 2022 | Sicilian Defense: Closed | |
| Apr 7, 2022 | Marzik | 1–0 | Hafthorsson | Kvika Reykjavik Open 2022 | Queen's Pawn Game: Symmetrical Variation, Pseudo-Catalan | |
| Apr 6, 2022 | Haraldsson | 1–0 | Hafthorsson | Kvika Reykjavik Open 2022 | Benoni Defense: Czech Benoni Defense | |
| Nov 28, 2021 | Hafthorsson | 0–1 | Fernlund | Juniorallsvenskan 2021 division 1 + 2 | Caro-Kann Defense: Advance Variation, Tal Variation | |
| Nov 28, 2021 | Storme | 1–0 | Hafthorsson | Juniorallsvenskan 2021 division 1 + 2 | Italian Game: Evans Gambit, Compromised Defense | |
| Nov 27, 2021 | Hafthorsson | 0–1 | Ostlund | Juniorallsvenskan 2021 division 1 + 2 | Caro-Kann Defense: Advance Variation, Tal Variation | |
| Nov 27, 2021 | Joensson | 1–0 | Hafthorsson | Juniorallsvenskan 2021 division 1 + 2 | Benoni Defense: Czech Benoni Defense | |
| Oct 8, 2021 | Bensryd | 1–0 | Hafthorsson | Skol-SM 2021, grupp A | Scotch Game: Scotch Gambit, Advance Variation | |
| — | Johansson | 1–0 | Hafthorsson | Jonkoping Chess Festival 2025 - Standard Open | Sicilian Defense: Nyezhmetdinov-Rossolimo Attack | |
