| Game |
| Result | Moves |
Year | Event/Locale | Opening |
| 1. G Simms vs D LaPierre Ballard |
| 0-1 | 30 | 1965 | Southwest Open | B32 Sicilian |
| 2. Benko vs G Simms |
 | 1-0 | 45 | 1967 | 68th US Open | B63 Sicilian, Richter-Rauzer Attack |
| 3. G Simms vs E Formanek |
| 0-1 | 18 | 1967 | 68th US Open | B59 Sicilian, Boleslavsky Variation, 7.Nb3 |
| 4. J Acers vs G Simms |
| 1-0 | 35 | 1968 | 69th US Open | E11 Bogo-Indian Defense |
| 5. G Simms vs D Kerman |
| 0-1 | 19 | 1968 | 69th US Open | B83 Sicilian |
| 6. S Subramanian vs G Simms |
| 1-0 | 33 | 1968 | 69th US Open | B88 Sicilian, Fischer-Sozin Attack |
| 7. R Newbold vs G Simms |
| ½-½ | 40 | 1971 | Lone Pine | E00 Queen's Pawn Game |
| 8. G Simms vs K Smith |
| 0-1 | 25 | 1971 | Denver Open | B83 Sicilian |
| 9. D LaPierre Ballard vs G Simms |
| 1-0 | 27 | 1971 | Southwest Open | A56 Benoni Defense |
| 10. V Pupols vs G Simms |
| ½-½ | 41 | 1982 | NWC July | A61 Benoni |
| 11. D Gurevich vs G Simms |
| 1-0 | 37 | 1989 | 7th Midwest Masters Invitational | E98 King's Indian, Orthodox, Taimanov, 9.Ne1 |
| 12. G Simms vs I Ivanov |
| 0-1 | 44 | 1989 | 7th Midwest Masters Invitational | B53 Sicilian |
| 13. G Simms vs W Lukowiak |
| 1-0 | 23 | 1989 | 7th Midwest Masters | C44 King's Pawn Game |
| 14. M Weiss vs G Simms |
| 1-0 | 77 | 1989 | 7th Midwest Masters | B42 Sicilian, Kan |
| 15. E Neely vs G Simms |
| 0-1 | 43 | 1989 | 7th Midwest Masters | B28 Sicilian, O'Kelly Variation |
| 16. G Simms vs E Karklins |
| 1-0 | 44 | 1989 | 7th Midwest Masters | C44 King's Pawn Game |
| 17. G Schwartzman vs G Simms |
| 1-0 | 21 | 1994 | 95th US Open | E62 King's Indian, Fianchetto |
| 18. J Wiewel vs G Simms |
| ½-½ | 28 | 1994 | 95th US Open | E77 King's Indian |
| 19. G Simms vs W G Cox |
| 1-0 | 57 | 1994 | 95th US Open | C40 King's Knight Opening |
| 20. D Arond vs G Simms |
| 0-1 | 26 | 1994 | 95th US Open | E92 King's Indian |
| 21. S Weeramantry vs G Simms |
| 1-0 | 18 | 1994 | 95th US Open | B23 Sicilian, Closed |
| 22. G Simms vs A Young |
| ½-½ | 51 | 1994 | 95th US Open | A07 King's Indian Attack |
| 23. G Simms vs K Flaga |
| 1-0 | 41 | 1994 | 95th US Open | A07 King's Indian Attack |
| 24. E Martinovsky vs G Simms |
| 1-0 | 34 | 1994 | 95th US Open | A49 King's Indian, Fianchetto without c4 |
| 25. D A Middleton vs G Simms |
| 0-1 | 40 | 1994 | 95th US Open | B32 Sicilian |
Kibitzing
