| 7 jun 2026 | Stelmaszyk, Nico 2359 | Bargsten, Justus 2255 | ½-½ | B22 Sicilian Defense: Alapin Variation | Pokalmannschaftsmeisterschaft Niedersachsen/Bremen | 41 | Ver |
| 7 jun 2026 | Stelmaszyk, Nico 2359 | Scheffner, Jarno 2039 | 1-0 | B22 Sicilian Defense: Alapin Variation | Pokalmannschaftsmeisterschaft Niedersachsen/Bremen | 44 | Ver |
| 6 jun 2026 | Mueer, Sebastian 2110 | Stelmaszyk, Nico 2359 | ½-½ | D35 Queen's Gambit Declined: Exchange Variation, Positional Variation | Pokalmannschaftsmeisterschaft Niedersachsen/Bremen | 23 | Ver |
| 6 jun 2026 | Stelmaszyk, Nico 2359 | Lichtmannecker, Daniel 2191 | 1-0 | C42 Petrov's Defense: Damiano Variation, Kholmov Gambit | Pokalmannschaftsmeisterschaft Niedersachsen/Bremen | 76 | Ver |
| 29 may 2026 | Stelmaszyk, Nico 2359 | Ciolek, Andreas 2193 | ½-½ | B40 Sicilian Defense: Delayed Alapin Variation, with e6 | Munich Chess Festival 2026 | Open A | 34 | Ver |
| 28 may 2026 | Weigand, Anton 2174 | Stelmaszyk, Nico 2359 | 1-0 | C54 Italian Game: Classical Variation, Giuoco Pianissimo | Munich Chess Festival 2026 | Open A | 51 | Ver |
| 27 may 2026 | Stoyanov, Tsvetan 2445 | Stelmaszyk, Nico 2359 | ½-½ | A21 English Opening: King's English Variation, Kramnik-Shirov Counterattack | Munich Chess Festival 2026 | Open A | 35 | Ver |
| 27 may 2026 | Stelmaszyk, Nico 2359 | Noe, Christopher 2517 | ½-½ | B01 Scandinavian Defense: Gubinsky-Melts Defense | Munich Chess Festival 2026 | Open A | 60 | Ver |
| 26 may 2026 | Stelmaszyk, Nico 2359 | Shen, Tingrui 2198 | 1-0 | B22 Sicilian Defense: Alapin Variation | Munich Chess Festival 2026 | Open A | 40 | Ver |
| 25 may 2026 | Chassard, Cedric 2232 | Stelmaszyk, Nico 2359 | ½-½ | B30 Sicilian Defense: Nyezhmetdinov-Rossolimo Attack | Munich Chess Festival 2026 | Open A | 21 | Ver |
| 25 may 2026 | Stelmaszyk, Nico 2359 | Puranik, Abhimanyu 2607 | 0-1 | C55 Italian Game: Two Knights Defense, Modern Bishop's Opening | Munich Chess Festival 2026 | Open A | 27 | Ver |
| 24 may 2026 | Khrapko, Marharyta 2100 | Stelmaszyk, Nico 2359 | 0-1 | B30 Sicilian Defense: Nyezhmetdinov-Rossolimo Attack | Munich Chess Festival 2026 | Open A | 47 | Ver |
| 23 may 2026 | Stelmaszyk, Nico 2359 | Straub, Juergen Dr. 2120 | 1-0 | C41 Philidor Defense: Lion Variation | Munich Chess Festival 2026 | Open A | 33 | Ver |
| 6 abr 2026 | Cervelli, Eduard 2191 | Stelmaszyk, Nico 2352 | ½-½ | B30 Sicilian Defense: Old Sicilian | Grenke Chess Festival 2026 Open | 52 | Ver |
| 5 abr 2026 | Stelmaszyk, Nico 2352 | Firman, Nazar 2458 | 0-1 | C70 Ruy Lopez: Morphy Defense, Classical Defense Deferred | Grenke Chess Festival 2026 Open | 59 | Ver |
| 5 abr 2026 | Schulte-Geers, Niklas 2180 | Stelmaszyk, Nico 2352 | 0-1 | D37 Queen's Gambit Declined: Knight Defense, Alekhine Gambit | Grenke Chess Festival 2026 Open | 46 | Ver |
| 4 abr 2026 | Stelmaszyk, Nico 2352 | Karthik Venkataraman 2594 | ½-½ | C09 French Defense: Tarrasch Variation, Open System, Main Line | Grenke Chess Festival 2026 Open | 47 | Ver |
| 4 abr 2026 | Stelmaszyk, Nico 2352 | Bashylina, Luisa 2151 | 1-0 | C22 Center Game: Normal Variation | Grenke Chess Festival 2026 Open | 52 | Ver |
| 3 abr 2026 | Kaufeld, Juergen 2204 | Stelmaszyk, Nico 2352 | ½-½ | B09 Pirc Defense: Austrian Attack, Kurajica Variation | Grenke Chess Festival 2026 Open | 17 | Ver |
| 31 mar 2026 | Vollbehr, Bjarne 2205 | Stelmaszyk, Nico 2355 | ½-½ | D02 Queen's Pawn Game: Symmetrical Variation, Pseudo-Catalan | Runde 9: Vollbehr, Bjarne - Stelmaszyk, Nico | 38 | Ver |
