| Jun 30, 2026 | Yalcinkaya | ½–½ | Kosakowski | Round 3: Yalcinkaya, Efe - Kosakowski, Jakub | Ruy Lopez: Morphy Defense, Classical Defense Deferred | |
| Jun 30, 2026 | Kosakowski | 1–0 | Dogan | Round 2: Kosakowski, Jakub - Dogan, Umut Anil | Pirc Defense: Classical Variation | |
| Jun 29, 2026 | Tarlabasi | ½–½ | Kosakowski | Round 1: Tarlabasi, Emirhan - Kosakowski, Jakub | Nimzo-Indian Defense: Normal Variation, Gligoric System, Exchange Variation | |
| Jun 27, 2026 | Kosakowski | 1–0 | Pultinevicius | Macieja Memorial | Caro-Kann Defense: Tartakower Variation | |
| Jun 27, 2026 | Mulawa | 0–1 | Kosakowski | Macieja Memorial | English Opening: Anglo-Indian Defense, King's Knight Variation | |
| Jun 27, 2026 | Kosakowski | 1–0 | Mayorau | Macieja Memorial | Modern Defense | |
| Jun 27, 2026 | Bartel | 0–1 | Kosakowski | Macieja Memorial | Caro-Kann Defense: Advance Variation, Short Variation | |
| Jun 27, 2026 | Kosakowski | 1–0 | Janeczko | Macieja Memorial | Alekhine Defense: Sämisch Attack | |
| Jun 27, 2026 | Wasiluk | 0–1 | Kosakowski | Macieja Memorial | Ruy Lopez: Morphy Defense, Classical Defense Deferred | |
| Jun 27, 2026 | Kosakowski | 0–1 | Terkiewicz | Macieja Memorial | Sicilian Defense: Modern Variations | |
| Jun 27, 2026 | Madejski | 0–1 | Kosakowski | Macieja Memorial | Indian Defense: Anti-Nimzo-Indian | |
| Jun 27, 2026 | Kosakowski | 1–0 | Obrycki | Macieja Memorial | Sicilian Defense: Modern Variations | |
| Jun 27, 2026 | Fistek | 1–0 | Kosakowski | Macieja Memorial | Bogo-Indian Defense: Nimzowitsch Variation | |
| Jun 27, 2026 | Kosakowski | 1–0 | Etut | Macieja Memorial | ? | |
| Jun 24, 2026 | Kosakowski | ½–½ | Nurkiewicz | Druzynowe Mistrzostwa Polski - Ekstraliga 2026 | Petrov's Defense | |
| Jun 23, 2026 | Kantans | 0–1 | Kosakowski | Druzynowe Mistrzostwa Polski - Ekstraliga 2026 | Bishop's Opening: Vienna Hybrid | |
| Jun 22, 2026 | Kosakowski | ½–½ | Szpar | Druzynowe Mistrzostwa Polski - Ekstraliga 2026 | Neo-Grünfeld Defense: Classical Variation, Original Defense | |
| Jun 21, 2026 | Mis | ½–½ | Kosakowski | Druzynowe Mistrzostwa Polski - Ekstraliga 2026 | Sicilian Defense: Nimzowitsch Variation, Advance Variation | |
| Jun 20, 2026 | Kosakowski | ½–½ | Malek | Druzynowe Mistrzostwa Polski - Ekstraliga 2026 | King's Indian Attack, with e6 | |
| Jun 19, 2026 | Cieslak | 1–0 | Kosakowski | Druzynowe Mistrzostwa Polski - Ekstraliga 2026 | Nimzo-Indian Defense: St. Petersburg Variation, American Variation | |
| Jun 18, 2026 | Kosakowski | 1–0 | Luch | Druzynowe Mistrzostwa Polski - Ekstraliga 2026 | King's Pawn Game: Alapin Opening | |
| Jun 17, 2026 | Kazakouski | 1–0 | Kosakowski | Druzynowe Mistrzostwa Polski - Ekstraliga 2026 | King's Indian Defense: Normal Variation, Standard Development | |
| Jun 16, 2026 | Kosakowski | 1–0 | Chylewski | Druzynowe Mistrzostwa Polski - Ekstraliga 2026 | Queen's Gambit Declined: Charousek Variation | |
| May 17, 2026 | Kosakowski | 1–0 | Puranik | Round 9: Kosakowski, Jakub - Puranik, Abhimanyu | Sicilian Defense: Richter-Rauzer Variation, Neo-Modern Variation | |
| May 16, 2026 | Sai Krishna G V | ½–½ | Kosakowski | Round 8: Sai Krishna G V - Kosakowski, Jakub | Ruy Lopez: Morphy Defense, Classical Defense Deferred | |
| May 15, 2026 | Kosakowski | ½–½ | Aizenberg | Round 7: Kosakowski, Jakub - Aizenberg, Benny | Sicilian Defense: Lasker-Pelikan Variation, Sveshnikov Variation, Chelyabinsk Variation | |
| May 14, 2026 | Kosakowski | 0–1 | Pranesh M | Round 5: Kosakowski, Jakub - Pranesh M | Sicilian Defense: Taimanov Variation, Bastrikov Variation, English Attack | |
| May 13, 2026 | Chasin | 0–1 | Kosakowski | Round 4: Chasin, Nico - Kosakowski, Jakub | King's Indian Attack: Symmetrical Defense | |
| May 4, 2026 | Jackson | ½–½ | Kosakowski | Round 11: Jackson, James P - Kosakowski, Jakub | Bogo-Indian Defense: Nimzowitsch Variation | |
| May 3, 2026 | Kosakowski | ½–½ | Maroroa Jones | Round 10: Kosakowski, Jakub - Maroroa Jones, Gawain C B | Italian Game: Two Knights Defense, Modern Bishop's Opening | |
| May 2, 2026 | Khoury | 0–1 | Kosakowski | Round 9: Khoury, Theo - Kosakowski, Jakub | Sicilian Defense: Najdorf Variation, Amsterdam Variation | |
| Apr 26, 2026 | Van Foreest | 1–0 | Kosakowski | Round 15: Van Foreest, Jorden - Kosakowski, Jakub | English Opening: Agincourt Defense | |
| Apr 25, 2026 | Kosakowski | ½–½ | Kuzubov | Round 14: Kosakowski, Jakub - Kuzubov, Yuriy | Four Knights Game: Scotch Variation Accepted | |
| Apr 24, 2026 | Kosakowski | ½–½ | Bacrot | BL 2526 SC Heimbach-Weis-Neuwied - OSG Baden-Baden | French Defense: Winawer Variation, Retreat Variation, Armenian Line | |
| Apr 23, 2026 | Kosakowski | ½–½ | Roshka | SVK Extraliga 2024/2025 | Sicilian Defense: Kan Variation | |
| Apr 23, 2026 | Bochnicka | ½–½ | Kosakowski | SVK Extraliga 2024/2025 | Caro-Kann Defense: Advance Variation, Botvinnik-Carls Defense | |
| Apr 19, 2026 | Hrbek | ½–½ | Kosakowski | EICC 2026 | King's Indian Defense: Orthodox Variation | |
| Apr 18, 2026 | Kosakowski | ½–½ | Tudor | EICC 2026 | Philidor Defense: Exchange Variation | |
| Apr 16, 2026 | Ivanchuk | 1–0 | Kosakowski | EICC 2026 | Catalan Opening: Closed | |
| Apr 15, 2026 | Kosakowski | ½–½ | Bjerre | EICC 2026 | Four Knights Game: Scotch Variation Accepted, Main Line | |
| Apr 14, 2026 | Donchenko | ½–½ | Kosakowski | EICC 2026 | Bogo-Indian Defense: Nimzowitsch Variation | |
| Apr 13, 2026 | Kosakowski | 1–0 | Dyachuk | EICC 2026 | Italian Game: Classical Variation, Giuoco Pianissimo | |
| Apr 12, 2026 | Sargsyan | ½–½ | Kosakowski | EICC 2026 | English Opening: Anglo-Indian Defense, King's Knight Variation | |
| Apr 10, 2026 | Kosakowski | 1–0 | Isik | EICC 2026 | French Defense: Winawer Variation, Bogoljubow Variation | |
| Apr 9, 2026 | Ambartsumian | 0–1 | Kosakowski | EICC 2026 | Sicilian Defense: Taimanov Variation | |
| Apr 8, 2026 | Kosakowski | ½–½ | Svanda | EICC 2026 | Sicilian Defense: Nyezhmetdinov-Rossolimo Attack, Fianchetto Variation, Lutikov Gambit | |
| Apr 7, 2026 | Tymrakiewicz | 0–1 | Kosakowski | EICC 2026 | Dutch Defense: Semi-Leningrad Variation | |
| Mar 30, 2026 | Moranda | ½–½ | Kosakowski | Indywidualne Mistrzostwa Polski 2026 | Bogo-Indian Defense: Grünfeld Variation | |
| Mar 29, 2026 | Kosakowski | ½–½ | Teclaf | Indywidualne Mistrzostwa Polski 2026 | Italian Game: Classical Variation, Giuoco Pianissimo | |
| Mar 27, 2026 | Socko | ½–½ | Kosakowski | Indywidualne Mistrzostwa Polski 2026 | Catalan Opening | |
| Mar 26, 2026 | Kosakowski | ½–½ | Licznerski | Indywidualne Mistrzostwa Polski 2026 | Caro-Kann Defense: Advance Variation, Short Variation | |
| Mar 25, 2026 | Malek | ½–½ | Kosakowski | Indywidualne Mistrzostwa Polski 2026 | Indian Defense: Normal Variation | |
| Mar 24, 2026 | Kosakowski | ½–½ | Wojtaszek | Indywidualne Mistrzostwa Polski 2026 | Four Knights Game: Scotch Variation Accepted | |
| Mar 23, 2026 | Zielonka | 0–1 | Kosakowski | Indywidualne Mistrzostwa Polski 2026 | Ruy Lopez: Morphy Defense, Schliemann Defense Deferred | |
| Mar 23, 2026 | Kosakowski | ½–½ | Gumularz | Indywidualne Mistrzostwa Polski 2026 | Italian Game: Classical Variation, Giuoco Pianissimo | |
| Mar 22, 2026 | Kosakowski | 1–0 | Bartel | Indywidualne Mistrzostwa Polski 2026 | Italian Game: Classical Variation, Giuoco Pianissimo | |
| Mar 1, 2026 | Horvath | ½–½ | Kosakowski | SBL München | Bogo-Indian Defense: Nimzowitsch Variation | |
| Feb 28, 2026 | Kosakowski | 1–0 | Banusz | SBL München | Sicilian Defense: Lasker-Pelikan Variation, Sveshnikov Variation, Chelyabinsk Variation | |
| Feb 8, 2026 | Kosakowski | 0–1 | Nisipeanu | Deutsche Schachbundesliga 2025/2026 | King's Knight Opening: Konstantinopolsky | |
| Feb 7, 2026 | Fromm | 1–0 | Kosakowski | Deutsche Schachbundesliga 2025/2026 | Sicilian Defense: Moscow Variation | |
| Jan 10, 2026 | Kovchan | ½–½ | Kosakowski | Round 3: Kovchan, Alexander - Kosakowski, Jakub | Sicilian Defense: Najdorf Variation, Zagreb Variation | |
| Dec 30, 2025 | Kosakowski | 0–1 | Pantsulaia | World Blitz 2025 Open | Sicilian Defense: Kan Variation | |
| Dec 30, 2025 | Niemann | 0–1 | Kosakowski | World Blitz 2025 Open | Sicilian Defense: Najdorf Variation | |
| Dec 30, 2025 | Kosakowski | 1–0 | Suleimen | World Blitz 2025 Open | Sicilian Defense: Najdorf Variation | |
| Dec 30, 2025 | Mitrabha | ½–½ | Kosakowski | World Blitz 2025 Open | English Opening: Agincourt Defense, Neo-Catalan Declined | |
| Dec 30, 2025 | Kosakowski | 0–1 | Aravindh | World Blitz 2025 Open | Sicilian Defense: Old Sicilian | |
| Dec 30, 2025 | Wojtaszek | ½–½ | Kosakowski | World Blitz 2025 Open | Dutch Defense: Normal Variation | |
| Dec 29, 2025 | Kosakowski | 1–0 | Galaviz Medina | World Blitz 2025 Open | Sicilian Defense: Old Sicilian | |
| Dec 29, 2025 | Balakrishnan | 0–1 | Kosakowski | World Blitz 2025 Open | Caro-Kann Defense: Advance Variation, Short Variation | |
| Dec 29, 2025 | Dau Khuong Duy | 1–0 | Kosakowski | World Blitz 2025 Open | Caro-Kann Defense: Two Knights Attack, Mindeno Variation, Exchange Line | |
| Dec 29, 2025 | Kosakowski | 0–1 | Maghsoodloo | World Blitz 2025 Open | Sicilian Defense: Modern Variations, Main Line | |
| Dec 29, 2025 | Kosakowski | ½–½ | Giri | World Blitz 2025 Open | Sicilian Defense: Najdorf Variation, Lipnitsky Attack | |
| Dec 29, 2025 | Nihal Sarin | 1–0 | Kosakowski | World Blitz 2025 Open | Nimzo-Indian Defense: Normal Variation | |
| Dec 29, 2025 | Kosakowski | 1–0 | Le | World Blitz 2025 Open | Scotch Game | |
| Dec 29, 2025 | Robson | ½–½ | Kosakowski | World Blitz 2025 Open | Nimzo-Indian Defense: Normal Variation, Botvinnik System | |
| Dec 29, 2025 | Kosakowski | 1–0 | Wafa | World Blitz 2025 Open | Scotch Game: Potter Variation | |
| Dec 29, 2025 | Gukesh D | 1–0 | Kosakowski | World Blitz 2025 Open | Sicilian Defense: Najdorf Variation, Zagreb Variation | |
| Dec 29, 2025 | Kosakowski | 1–0 | Fandi | World Blitz 2025 Open | Caro-Kann Defense: Advance Variation, Short Variation | |
| Dec 29, 2025 | Harikrishna | 1–0 | Kosakowski | World Blitz 2025 Open | Sicilian Defense: Modern Variations | |
| Dec 28, 2025 | Kosakowski | 1–0 | Khayat | World Blitz 2025 Open | Scotch Game: Malaniuk Variation | |
| Dec 28, 2025 | Motylev | 1–0 | Kosakowski | WRBC 2025 Rapid Open | Catalan Opening: Open Defense, Classical Line | |
| Dec 28, 2025 | Kosakowski | 1–0 | Chigaev | WRBC 2025 Rapid Open | Scotch Game: Romanishin Variation | |
| Dec 28, 2025 | Kosakowski | ½–½ | Bu | WRBC 2025 Rapid Open | Petrov's Defense: Classical Attack, Staunton Variation | |
| Dec 28, 2025 | Giri | 1–0 | Kosakowski | WRBC 2025 Rapid Open | Sicilian Defense: Moscow Variation | |
| Dec 27, 2025 | Praggnanandhaa R | ½–½ | Kosakowski | WRBC 2025 Rapid Open | English Opening: King's English Variation, Four Knights Variation, Fianchetto Line, with Nb6 | |
| Dec 27, 2025 | Kosakowski | ½–½ | Sevian | WRBC 2025 Rapid Open | Scotch Game: Schmidt Variation | |
| Dec 27, 2025 | Kosakowski | ½–½ | Matlakov | WRBC 2025 Rapid Open | Sicilian Defense: Taimanov Variation | |
| Dec 27, 2025 | Esipenko | 0–1 | Kosakowski | WRBC 2025 Rapid Open | Sicilian Defense: Najdorf Variation | |
| Dec 26, 2025 | Kosakowski | 1–0 | Jobava | WRBC 2025 Rapid Open | French Defense: Rubinstein Variation, Fort Knox Variation | |
| Dec 26, 2025 | Mamedov | 1–0 | Kosakowski | WRBC 2025 Rapid Open | Sicilian Defense: Delayed Alapin Variation | |
| Dec 26, 2025 | Ivanchuk | ½–½ | Kosakowski | WRBC 2025 Rapid Open | Nimzo-Indian Defense: Classical Variation | |
| Dec 26, 2025 | Kosakowski | 1–0 | Rami | WRBC 2025 Rapid Open | Caro-Kann Defense: Advance Variation, Short Variation | |
| Dec 19, 2025 | Kosakowski | ½–½ | Prraneeth Vuppala | Wroclaw Chess Festival 2025 - OPEN A | Italian Game: Giuoco Pianissimo, Normal | |
| Dec 18, 2025 | Yaniv | ½–½ | Kosakowski | Wroclaw Chess Festival 2025 - OPEN A | Sicilian Defense: Najdorf Variation, Lipnitsky Attack | |
| Dec 18, 2025 | Kosakowski | 1–0 | Grandelius | WRBC 2025 Rapid Open | Caro-Kann Defense: Advance Variation, Botvinnik-Carls Defense | |
| Dec 17, 2025 | Kosakowski | 1–0 | Ochedzan | Wroclaw Chess Festival 2025 - OPEN A | Sicilian Defense: Nyezhmetdinov-Rossolimo Attack | |
| Dec 17, 2025 | Sammed Jaykumar | ½–½ | Kosakowski | Wroclaw Chess Festival 2025 - OPEN A | Sicilian Defense: Moscow Variation | |
| Dec 16, 2025 | Kosakowski | ½–½ | Dhulipalla Bala Chandra Prasad | Wroclaw Chess Festival 2025 - OPEN A | Italian Game: Two Knights Defense, Modern Bishop's Opening | |
| Dec 15, 2025 | Shyaam Nikhil P | ½–½ | Kosakowski | Wroclaw Chess Festival 2025 - OPEN A | Queen's Gambit Declined: Queen's Knight Variation | |
| Dec 15, 2025 | Kosakowski | 1–0 | Vijayakumar | Wroclaw Chess Festival 2025 - OPEN A | Ruy Lopez: Closed, Martinez Variation | |