| 17 may 2026 | Van Dael, Siem 2278 | Milanovic, Danilo 2439 | 0-1 | B01 Defensa Escandinava: Gubinsky-Melts Defense | Grand Prix PlusCity | Open Austrian Championship | Rapid Team | 55 | Ver |
| 15 may 2026 | Van Dael, Siem 2205 | Kadric, Denis 2497 | 0-1 | C41 Defensa Philidor: Lion Variation | Grand Prix PlusCity | Open Austrian Championship | Blitz | 48 | Ver |
| 15 may 2026 | Van Dael, Siem 2205 | Santos Latasa, Jaime 2600 | 0-1 | B90 Defensa Siciliana: Najdorf Variation, English Attack | Grand Prix PlusCity | Open Austrian Championship | Blitz | 48 | Ver |
| 14 may 2026 | Henriquez Villagra, Cristobal 2605 | Van Dael, Siem 2278 | 1-0 | B90 Defensa Siciliana: Najdorf Variation, Adams Attack | Grand Prix PlusCity | Open Austrian Championship | Rapid | 44 | Ver |
| 14 may 2026 | Subelj, Jan 2536 | Van Dael, Siem 2278 | 1-0 | B52 Defensa Siciliana: Moscow Variation, Main Line | Grand Prix PlusCity | Open Austrian Championship | Rapid | 30 | Ver |
| 11 abr 2026 | Vrolijk, Liam 2529 | Van Dael, Siem 2333 | 1-0 | E73 Defensa India de Rey: Normal Variation, Standard Development | Dutch Meesterklasse 2025/26 | 50 | Ver |
| 6 abr 2026 | Van Dael, Siem 2333 | Karacsonyi, Kata 2134 | 1-0 | B22 Defensa Siciliana: Alapin Variation, Barmen Defense | Grenke Chess Festival 2026 Open | 34 | Ver |
| 5 abr 2026 | Dobrosmyslov, Artem 2221 | Van Dael, Siem 2333 | 0-1 | E90 Defensa India de Rey: Normal Variation, Rare Defenses | Grenke Chess Festival 2026 Open | 108 | Ver |
| 5 abr 2026 | Van Dael, Siem 2333 | Zeng, Chongsheng 2546 | 0-1 | B48 Defensa Siciliana: Taimanov Variation, Bastrikov Variation, English Attack | Grenke Chess Festival 2026 Open | 36 | Ver |
| 4 abr 2026 | Beerdsen, Thomas 2524 | Van Dael, Siem 2333 | ½-½ | B93 Defensa Siciliana: Najdorf Variation, Amsterdam Variation | Grenke Chess Festival 2026 Open | 21 | Ver |
| 4 abr 2026 | Van Dael, Siem 2333 | Fuchs, Dominik 2004 | 1-0 | C11 Defensa Francesa: Classical Variation, Burn Variation, Morozevich Line | Grenke Chess Festival 2026 Open | 21 | Ver |
| 28 mar 2026 | Kokje, Joris 2269 | Van Dael, Siem 2301 | 0-1 | A65 Defensa Benoni: King's Pawn Line, with Nge2 | Dutch Meesterklasse 2025/26 | 54 | Ver |
| 7 mar 2026 | Van Dael, Siem 2301 | Van Rootselaar, Rik 2211 | 1-0 | B32 Defensa Siciliana: Kalashnikov Variation | Dutch Meesterklasse 2025/26 | 62 | Ver |
| 7 feb 2026 | Ritzerveld, Noah 2236 | Van Dael, Siem 2281 | 0-1 | B84 Defensa Siciliana: Scheveningen Variation, Classical Variation | Dutch Meesterklasse 2025/26 | 41 | Ver |
| 22 nov 2025 | Rijnaarts, Sjef 2270 | Van Dael, Siem 2256 | 0-1 | B33 Defensa Siciliana: Lasker-Pelikan Variation, Sveshnikov Variation, Chelyabinsk Variation | Dutch Meesterklasse 2025/26 | 45 | Ver |
| 4 oct 2025 | Heemskerk, Wim 2167 | Van Dael, Siem 2260 | 0-1 | A05 Ataque Indio de Rey: Symmetrical Defense | Dutch Meesterklasse 2025/26 | 102 | Ver |