| Game |
| Result | Moves |
Year | Event/Locale | Opening |
| 1. J Alderson vs J Hardinge |
| 0-1 | 24 | 1964 | Trinity I v Trinity II | B07 Pirc |
| 2. J Alderson vs F Boyd |
| 0-1 | 13 | 1970 | ENG corr | C33 King's Gambit Accepted |
| 3. J Alderson vs B Rozycki |
| 0-1 | 45 | 2014 | London Chess Classic Open | A25 English |
| 4. R C Cannon vs J Alderson |
| 1-0 | 38 | 2014 | London Chess Classic Open | B01 Scandinavian |
| 5. J Alderson vs H Anbukumar |
| 1-0 | 50 | 2014 | London Chess Classic Open | B23 Sicilian, Closed |
| 6. D J White vs J Alderson |
| 0-1 | 27 | 2014 | London Chess Classic Open | B01 Scandinavian |
| 7. D Coleman vs J Alderson |
| 1-0 | 57 | 2014 | London Chess Classic Open | B01 Scandinavian |
| 8. J Alderson vs S Praczukowski |
| 0-1 | 49 | 2014 | London Chess Classic Open | A22 English |
| 9. R Cohen vs J Alderson |
| ½-½ | 18 | 2014 | London Chess Classic Open | B01 Scandinavian |
| 10. J Alderson vs K Kalavannan |
| ½-½ | 30 | 2014 | London Chess Classic Open | A10 English |
| 11. E Player vs J Alderson |
| 1-0 | 48 | 2016 | London Chess Classic Open | B07 Pirc |
| 12. J Alderson vs N Thatte |
| 0-1 | 56 | 2016 | London Chess Classic Open | A23 English, Bremen System, Keres Variation |
| 13. L Dror vs J Alderson |
| ½-½ | 34 | 2016 | London Chess Classic Open | B00 Uncommon King's Pawn Opening |
| 14. J Alderson vs T Lie |
| 1-0 | 52 | 2016 | London Chess Classic Open | A17 English |
| 15. Reinhard2 Kuntner vs J Alderson |
| 0-1 | 31 | 2016 | London Chess Classic Open | A20 English |
| 16. F M Tummasarson vs J Alderson |
 | 0-1 | 48 | 2018 | Reykjavik Open | C01 French, Exchange |
| 17. J Alderson vs J Kvamme |
| ½-½ | 40 | 2018 | Reykjavik Open | A15 English |
| 18. F Diaz vs J Alderson |
| 1-0 | 40 | 2018 | Reykjavik Open | C11 French |
| 19. J Alderson vs M M Jacobsen |
| 0-1 | 30 | 2018 | Reykjavik Open | A15 English |
| 20. J Alderson vs Baldur Heidar Sigurdsson |
| 1-0 | 51 | 2018 | Reykjavik Open | A16 English |
| 21. L Janzelj vs J Alderson |
| 1-0 | 37 | 2018 | Reykjavik Open | D27 Queen's Gambit Accepted, Classical |
| 22. J Alderson vs P Hardarson |
| ½-½ | 44 | 2018 | Reykjavik Open | A15 English |
| 23. G Runarsson vs J Alderson |
| ½-½ | 30 | 2018 | Reykjavik Open | C01 French, Exchange |
| 24. J Alderson vs N Hagesaether |
| 0-1 | 49 | 2024 | Cambridge International Open | A22 English |
| 25. L Martin vs J Alderson |
| 1-0 | 26 | 2024 | Cambridge International Open | A20 English |
Kibitzing
