| Aug 14, 2024 | Gretarsson | 1–0 | Eliseev | Lewis Chess Legends Open | Queen's Gambit Declined: Janowski Variation | |
| Aug 13, 2024 | Haug | ½–½ | Gretarsson | Lewis Chess Legends Open | Sicilian Defense: Delayed Alapin Variation | |
| Aug 12, 2024 | Deuer | ½–½ | Gretarsson | Lewis Chess Legends Open | Nimzo-Indian Defense: Normal Variation | |
| Aug 11, 2024 | Gretarsson | 1–0 | Stanford | Lewis Chess Legends Open | Sicilian Defense: Najdorf Variation | |
| Aug 10, 2024 | Gretarsson | ½–½ | Cramling | Lewis Chess Legends Open | Sicilian Defense: Scheveningen Variation, Tal Variation | |
| Aug 9, 2024 | Urkedal | 1–0 | Gretarsson | Lewis Chess Legends Open | Ruy Lopez: Berlin Defense, Rio Gambit Accepted | |
| Aug 8, 2024 | Gretarsson | 1–0 | Fiskaaen | Lewis Chess Legends Open | Sicilian Defense: Najdorf Variation | |
| Aug 7, 2024 | Oye-Stromberg | ½–½ | Gretarsson | Lewis Chess Legends Open | Caro-Kann Defense: Two Knights Attack | |
| Aug 6, 2024 | Gretarsson | 1–0 | Gajcin | Lewis Chess Legends Open | English Opening: Symmetrical Variation, Rubinstein Variation | |
| Nov 20, 2023 | Gretarsson | ½–½ | Yilmaz | European Team Championship | Nimzo-Indian Defense: Normal Variation, Ragozin Variation | |
| Nov 19, 2023 | Bjerre | 0–1 | Gretarsson | European Team Championship | Ruy Lopez: Berlin Defense | |
| Nov 18, 2023 | Gretarsson | 1–0 | Muir | European Team Championship | Sicilian Defense: Richter-Rauzer Variation, Classical Variation | |
| Nov 17, 2023 | Anton Guijarro | ½–½ | Gretarsson | European Team Championship | English Opening: King's English Variation, Four Knights Variation, Flexible Line | |
| Nov 14, 2023 | Gretarsson | ½–½ | Erdos | European Team Championship | Queen's Gambit Declined: Exchange Variation, Positional Variation | |
| Nov 13, 2023 | Carlsen | 1–0 | Gretarsson | European Team Championship | Ruy Lopez: Morphy Defense, Anderssen Variation | |
| Nov 12, 2023 | Gretarsson | 1–0 | Saraci | European Team Championship | Queen's Gambit Declined: Harrwitz Attack, Orthodox Defense | |
| Nov 11, 2023 | Sarana | 1–0 | Gretarsson | European Team Championship | Queen's Gambit Declined: Tartakower Defense | |
| May 25, 2023 | Gretarsson | 1–0 | Ptacnikova | Icelandic Chess Championship 2023 | Sicilian Defense: Accelerated Dragon, Maróczy Bind, Breyer Variation | |
| May 24, 2023 | Heimisson | ½–½ | Gretarsson | Icelandic Chess Championship 2023 | Four Knights Game: Gunsberg Variation | |
| May 22, 2023 | Thorfinnsson | 0–1 | Gretarsson | Icelandic Chess Championship 2023 | Sicilian Defense: Najdorf Variation | |
| May 20, 2023 | Domalchuk-Jonasson | 1–0 | Gretarsson | Icelandic Chess Championship 2023 | English Opening: King's English Variation, Three Knights System | |
| May 19, 2023 | Gretarsson | 1–0 | Danielsen | Icelandic Chess Championship 2023 | Petrov's Defense: Classical Attack, Mason-Showalter Variation | |
| Apr 1, 2023 | Gretarsson | 0–1 | Fitzsimons | Reykjavik Open 2023 | Bird Opening: Dutch Variation | |
| Apr 1, 2023 | Can | 1–0 | Gretarsson | Reykjavik Open 2023 | Catalan Opening: Closed | |
| Mar 31, 2023 | Gretarsson | 1–0 | Knaak | Reykjavik Open | Semi-Slav Defense: Marshall Gambit, Forgotten Variation | |
| Mar 30, 2023 | Gretarsson | 1–0 | Gaal | Reykjavik Open 2023 | Queen's Gambit Declined: Semi-Tarrasch Defense | |
| Mar 29, 2023 | Ruiz Buendia | 0–1 | Gretarsson | Reykjavik Open 2023 | Caro-Kann Defense: Advance Variation | |
| Mar 19, 2023 | Gretarsson | 1–0 | Pakleza | Icelandic Team Championship | Slav Defense | |
| Mar 18, 2023 | Gretarsson | 0–1 | Gretarsson | Icelandic Team Championship | Slav Defense: Quiet Variation, Pin Defense | |
| Mar 18, 2023 | Briem | 0–1 | Gretarsson | Icelandic Team Championship | Catalan Opening: Closed | |
| Mar 17, 2023 | Stremavicius | 0–1 | Gretarsson | Icelandic Team Championship | Zukertort Opening | |
| Nov 6, 2022 | Gretarsson | 0–1 | Bluebaum | FIDE World Fischer Random Championship - Finals | ? | |
| Oct 30, 2022 | Gretarsson | 0–1 | Bluebaum | FIDE World Fischer Random Championship - Finals | ? | |
| Oct 30, 2022 | Bluebaum | ½–½ | Gretarsson | FIDE World Fischer Random Championship - Finals | ? | |
| Oct 30, 2022 | Bluebaum | ½–½ | Gretarsson | FIDE World Fischer Random Championship - Finals | ? | |
| Oct 27, 2022 | Gretarsson | 0–1 | So | FIDE World Fischer Random Championship - Group A | ? | |
| Oct 27, 2022 | Gretarsson | 0–1 | Nepomniachtchi | FIDE World Fischer Random Championship - Group A | ? | |
| Oct 27, 2022 | So | 0–1 | Gretarsson | FIDE World Fischer Random Championship - Group A | ? | |
| Oct 27, 2022 | Nepomniachtchi | 1–0 | Gretarsson | FIDE World Fischer Random Championship - Group A | ? | |
| Oct 26, 2022 | Gretarsson | 0–1 | Abdusattorov | FIDE World Fischer Random Championship - Group A | ? | |
| Oct 26, 2022 | Gretarsson | 0–1 | Abdusattorov | FIDE World Fischer Random Championship - Group A | ? | |
| Oct 26, 2022 | Abdusattorov | 1–0 | Gretarsson | FIDE World Fischer Random Championship - Group A | ? | |
| Oct 26, 2022 | Abdusattorov | 1–0 | Gretarsson | FIDE World Fischer Random Championship - Group A | ? | |
| Oct 25, 2022 | Gretarsson | ½–½ | So | FIDE World Fischer Random Championship - Group A | ? | |
| Oct 25, 2022 | Gretarsson | 0–1 | Nepomniachtchi | FIDE World Fischer Random Championship - Group A | ? | |
| Oct 25, 2022 | So | 1–0 | Gretarsson | FIDE World Fischer Random Championship - Group A | ? | |
| Oct 25, 2022 | Nepomniachtchi | 1–0 | Gretarsson | FIDE World Fischer Random Championship - Group A | ? | |
| Oct 16, 2022 | Hjartarson | 0–1 | Gretarsson | Icelandic Team Championship | Queen's Gambit Declined: Barmen Variation | |
| Oct 15, 2022 | Gretarsson | 1–0 | Gislason | Icelandic Team Championship | King's Indian Defense: Makogonov Variation | |
| Oct 15, 2022 | Sulypa | 0–1 | Gretarsson | Icelandic Team Championship | Caro-Kann Defense: Advance Variation, Short Variation | |
| Oct 14, 2022 | Gretarsson | 1–0 | Ragnarsson | Icelandic Team Championship | Sicilian Defense: Taimanov Variation | |
| May 1, 2022 | Heimisson | 0–1 | Gretarsson | Icelandic Chess Championship 2022 | English Opening: King's English Variation, Four Knights Variation, Fianchetto Line, with Nb6 | |
| Apr 30, 2022 | Gretarsson | 1–0 | Stefansson | Icelandic Chess Championship 2022 | Sicilian Defense: Moscow Variation | |
| Apr 27, 2022 | Steingrimsson | 0–1 | Gretarsson | Icelandic Chess Championship 2022 | Nimzo-Indian Defense: Normal Variation, Botvinnik System | |
| Apr 26, 2022 | Gretarsson | 1–0 | Mai | Icelandic Chess Championship 2022 | Nimzo-Larsen Attack: Modern Variation | |
| Apr 25, 2022 | Gretarsson | ½–½ | Kjartansson | Icelandic Chess Championship 2022 | Italian Game: Two Knights Defense, Modern Bishop's Opening | |
| Apr 24, 2022 | Thorhallsson | 0–1 | Gretarsson | Icelandic Chess Championship 2022 | Slav Defense: Quiet Variation, Schallopp Defense | |
| Apr 23, 2022 | Gretarsson | 1–0 | Stefansson | Icelandic Chess Championship 2022 | Nimzo-Indian Defense: Classical Variation, Noa Variation | |
| Apr 22, 2022 | Thorfinnsson | ½–½ | Gretarsson | Icelandic Chess Championship 2022 | French Defense: Advance Variation, Euwe Variation | |
| Apr 21, 2022 | Gretarsson | ½–½ | Thorhallsson | Icelandic Chess Championship 2022 | Sicilian Defense: Richter-Rauzer Variation | |
| Apr 12, 2022 | Jarmula | 0–1 | Gretarsson | ROpen 2022 | Sicilian Defense: Taimanov Variation, Bastrikov Variation | |
| Apr 11, 2022 | Gretarsson | 1–0 | Willow | ROpen 2022 | King's Indian Attack | |
| Apr 10, 2022 | Gretarsson | 1–0 | Sarkar | ROpen 2022 | English Opening: King's English Variation, Two Knights Variation, Reversed Dragon | |
| Apr 10, 2022 | Korley | ½–½ | Gretarsson | ROpen 2022 | Slav Indian | |
| Apr 9, 2022 | Niemann | 1–0 | Gretarsson | ROpen 2022 | Sicilian Defense: Taimanov Variation, Bastrikov Variation | |
| Apr 7, 2022 | Gretarsson | 1–0 | Dishman | Reykjavik Open 2022 | Caro-Kann Defense: Endgame Variation | |
| Nov 21, 2021 | Gretarsson | ½–½ | Saraci | 23rd European Team Chess Championship 2021 - Open | English Opening: Symmetrical Variation, Four Knights Variation | |
| Nov 20, 2021 | Navara | 1–0 | Gretarsson | 23rd European Team Chess Championship 2021 - Open | Sicilian Defense: Moscow Variation | |
| Nov 19, 2021 | Gretarsson | 0–1 | Dardha | 23rd European Team Chess Championship 2021 - Open | Queen's Gambit Declined: Queen's Knight Variation | |
| Nov 18, 2021 | Grandelius | ½–½ | Gretarsson | 23rd European Team Chess Championship 2021 - Open | Sicilian Defense: Moscow Variation | |
| Nov 16, 2021 | Gretarsson | 1–0 | Toczek | 23rd European Team Chess Championship 2021 - Open | Benoni Defense: Taimanov Variation | |
| Nov 15, 2021 | Gretarsson | 1–0 | Nikolovski | 23rd European Team Chess Championship 2021 - Open | Benoni Defense: Taimanov Variation | |
| Nov 13, 2021 | Gretarsson | 0–1 | Agopov | 23rd European Team Chess Championship 2021 - Open | Nimzo-Larsen Attack: Indian Variation | |
| Nov 12, 2021 | Anton Guijarro | 1–0 | Gretarsson | 23rd European Team Chess Championship 2021 - Open | Queen's Gambit Declined: Barmen Variation | |
| Sep 2, 2021 | Kaasen | ½–½ | Gretarsson | European Individual Chess Championship 2021 - Reykjavik Open | Caro-Kann Defense: Two Knights Attack, Mindeno Variation, Exchange Line | |
| Sep 1, 2021 | Gretarsson | 0–1 | Maurizzi | European Individual Chess Championship 2021 - Reykjavik Open | Slav Defense: Modern Line | |
| Aug 31, 2021 | Grigorian | 1–0 | Gretarsson | European Individual Chess Championship 2021 - Reykjavik Open | English Defense | |
| Aug 30, 2021 | Gretarsson | 1–0 | Kjartansson | European Individual Chess Championship 2021 - Reykjavik Open | Benoni Defense | |
| Aug 29, 2021 | Nagy | 1–0 | Gretarsson | European Individual Chess Championship 2021 - Reykjavik Open | Queen's Indian Defense: Fianchetto Variation, Nimzowitsch Variation, Quiet Line | |
| Aug 28, 2021 | Gretarsson | ½–½ | Bluebaum | European Individual Chess Championship 2021 - Reykjavik Open | English Opening: Four Knights System, Nimzowitsch Variation | |
| Aug 27, 2021 | Petenyi | 0–1 | Gretarsson | European Individual Chess Championship 2021 - Reykjavik Open | Sicilian Defense: Closed, Traditional | |
| Aug 26, 2021 | Gretarsson | 1–0 | Kanyamarala | European Individual Chess Championship 2021 - Reykjavik Open | King's Indian Attack | |
| Jul 14, 2021 | Gretarsson | 1–0 | Stupak | FIDE World Cup | French Defense: Steinitz Variation, Boleslavsky Variation | |
| Jul 14, 2021 | Stupak | ½–½ | Gretarsson | FIDE World Cup | English Opening: Agincourt Defense, Catalan Defense Accepted | |
| — | Gretarsson | 1–0 | Stefansson | Íslandsbikarinn 2021 | English Opening: Four Knights System, Nimzowitsch Variation | |
| — | Gretarsson | 1–0 | Larkin | ROpen 2022 | English Opening: King's English Variation | |
| — | Gretarsson | 1–0 | Dauth | Reykjavik Open 2023 | Slav Defense: Modern Line | |
| — | Gretarsson | ½–½ | Hjartarson | Icelandic Chess Championship 2023 | Sicilian Defense: Kan Variation, Modern Variation | |
| — | Gretarsson | 0–1 | Kjartansson | Icelandic Chess Championship 2023 | Ruy Lopez: Berlin Defense | |
| — | Gretarsson | 1–0 | Ingvason | Icelandic Chess Championship 2023 | Slav Defense: Modern Line | |
| — | Gretarsson | 0–1 | Stefansson | Icelandic Chess Championship 2023 | Nimzo-Indian Defense: Classical Variation | |
| — | Gretarsson | 1–0 | Heimisson | Icelandic Team Championship | Ruy Lopez: Berlin Defense, Rio Gambit Accepted | |
| — | Gretarsson | ½–½ | Lomasov | Icelandic Team Championship | Tarrasch Defense: Symmetrical Variation | |
| — | Gretarsson | 0–1 | Prudnykova | Icelandic Chess Championship 2024 | Sicilian Defense: Prins Variation | |
| — | Gretarsson | ½–½ | Stefansson | Icelandic Chess Championship 2024 | Queen's Pawn Game: London System | |
| — | Gretarsson | 1–0 | Domalchuk-Jonasson | Icelandic Chess Championship 2024 | Ruy Lopez: Morphy Defense, Schliemann Defense Deferred | |
| — | Gretarsson | ½–½ | Stefansson | Icelandic Chess Championship 2024 | Queen's Gambit Declined: Charousek Variation | |
| — | Gretarsson | 1–0 | Ptacnikova | Icelandic Chess Championship 2024 | Sicilian Defense: Accelerated Dragon, Maróczy Bind | |
| — | Gretarsson | 1–0 | Steingrimsson | Icelandic Chess Championship 2024 | ? | |
| — | Stefansson | 0–1 | Gretarsson | Íslandsbikarinn 2021 | Sicilian Defense: Najdorf Variation | |