| T191-C65LSS· Sep 19 – 21, 2021 | Sep 19 – 21, 2021 | Classical | 6 | 1710 | 22 |
Panchenko Mem Open B 2021 Chelyabinsk RUS· Sep 13 – 21, 2021 | Sep 13 – 21, 2021 | Classical | 59 | 1986 | 270 |
Primorsko Open 2021 Primorsko BUL· Sep 13 – 21, 2021 | Sep 13 – 21, 2021 | Classical | 62 | 2062 | 138 |
Panchenko Mem Open A 2021 Chelyabinsk RUS· Sep 13 – 21, 2021 | Sep 13 – 21, 2021 | Classical | 150 | 2225 | 717 |
Panticapaeum Cup 2021 Kerch RUS· Sep 12 – 20, 2021 | Sep 12 – 20, 2021 | Classical | 19 | 2053 | 78 |
| FICGS__CHESS__CUP_CHAMPIONSHIP__000004FICGS· Sep 20, 2021 | Sep 20, 2021 | Classical | 34 | 2165 | 511 |
| OP-05189LSS· Sep 20, 2021 | Sep 20, 2021 | Classical | 5 | 1460 | 9 |
| OP-05188LSS· Sep 18 – 19, 2021 | Sep 18 – 19, 2021 | Classical | 4 | 1753 | 5 |
Hendon 2300 Plus London ENG· Sep 17 – 19, 2021 | Sep 17 – 19, 2021 | Classical | 8 | 2348 | 18 |
Barreau de Paris Elite Paris FRA· Sep 5 – 19, 2021 | Sep 5 – 19, 2021 | Classical | 6 | 2395 | 28 |
XXVII San Miguel Open 2021 Trevias ESP· Sep 18 – 19, 2021 | Sep 18 – 19, 2021 | Classical | 9 | 2151 | 12 |
PGNiG POL Bydgoszcz KO Bydgoszcz POL· Sep 19, 2021 | Sep 19, 2021 | Classical | 16 | 2442 | 35 |
PGNiG POL Bydgoszcz Blitz Bydgoszcz POL· Sep 19, 2021 | Sep 19, 2021 | Blitz | 83 | 2137 | 141 |
CZE Ch Women 2021 Frydek Mistek CZE· Sep 11 – 19, 2021 | Sep 11 – 19, 2021 | Classical | 10 | 2181 | 45 |
| EE Sept Blitz Open 2021Europe-Echecs INT· Sep 19, 2021 | Sep 19, 2021 | Blitz | 97 | 1835 | 483 |
SVK Club Cup 2021 Kremnica SVK· Sep 15 – 19, 2021 | Sep 15 – 19, 2021 | Classical | 40 | 2059 | 111 |
| QA-00013LSS· Sep 17 – 18, 2021 | Sep 17 – 18, 2021 | Classical | 4 | 2058 | 12 |
| FICGS__CHESS__CLASS_GM__000007FICGS· Sep 18, 2021 | Sep 18, 2021 | Classical | 7 | 2265 | 20 |
Ahilik International Open Kirsehir TUR· Sep 13 – 18, 2021 | Sep 13 – 18, 2021 | Classical | 32 | 1960 | 115 |
PGNiG Polish Bydgoszcz Pr Bydgoszcz POL· Sep 18, 2021 | Sep 18, 2021 | Classical | 120 | 2137 | 176 |
9. Norway Chess 2021 Stavanger NOR· Sep 7 – 17, 2021 | Sep 7 – 17, 2021 | Classical | 7 | 2743 | 40 |
Norway Chess Open Masters Stavanger NOR· Sep 10 – 17, 2021 | Sep 10 – 17, 2021 | Classical | 33 | 2239 | 119 |
| OP-05187LSS· Sep 15 – 16, 2021 | Sep 15 – 16, 2021 | Classical | 6 | 1386 | 9 |
| FICGS__CHESS__RAPID_A__000274FICGS· Sep 16, 2021 | Sep 16, 2021 | Classical | 6 | 1846 | 15 |
| T190-E41LSS· Sep 15 – 16, 2021 | Sep 15 – 16, 2021 | Classical | 6 | 1715 | 28 |
TCh-SRB Premier w 2021 Vrnjacka Banja SRB· Sep 7 – 16, 2021 | Sep 7 – 16, 2021 | Classical | 60 | 2060 | 226 |
TCh-SRB Premier 2021 Vrnjacka Banja SRB· Sep 7 – 16, 2021 | Sep 7 – 16, 2021 | Classical | 86 | 2348 | 356 |
POR Ch 2021 Evora POR· Sep 7 – 15, 2021 | Sep 7 – 15, 2021 | Classical | 12 | 2246 | 57 |
Kyiv-Lviv Region Blitz Kiev UKR· Sep 15, 2021 | Sep 15, 2021 | Blitz | 40 | 2175 | 150 |
Kyiv-Lviv Region Rapid Kiev UKR· Sep 14, 2021 | Sep 14, 2021 | Rapid | 40 | 2175 | 74 |
1. Int Swiss Masters 2021 Baden-Baden GER· Sep 9 – 14, 2021 | Sep 9 – 14, 2021 | Classical | 26 | 2226 | 114 |
| FICGS__CHESS__CLASS_C__000296FICGS· Sep 14, 2021 | Sep 14, 2021 | Classical | 7 | 1735 | 11 |
TCh-ESP Div 1 2021 Linares ESP· Sep 8 – 14, 2021 | Sep 8 – 14, 2021 | Classical | 60 | 2276 | 174 |
| T183-C50LSS· Sep 13, 2021 | Sep 13, 2021 | Classical | 8 | 2152 | 34 |
48. Greek Team Championship (Group 1) Athens GRE· Sep 8 – 12, 2021 | Sep 8 – 12, 2021 | Classical | 10 | 1183 | 7 |
| JSM 1. div. 2020-22Uurainen· Sep 11 – 12, 2021 | Sep 11 – 12, 2021 | Classical | 24 | 1897 | 16 |
| 48. Greek Team Championship (Group 1)· Sep 7 – 12, 2021 | Sep 7 – 12, 2021 | Classical | 20 | 1390 | 14 |
ch-Nordic Youth Gp A 2021 Torshavn FAI· Sep 10 – 12, 2021 | Sep 10 – 12, 2021 | Classical | 12 | 2080 | 35 |
Asnieres-sur-Seine Trophy Asnieres-sur-Seine FRA· Sep 11 – 12, 2021 | Sep 11 – 12, 2021 | Classical | 29 | 2164 | 44 |
Orasului Cup 2021 Tasnad ROU· Sep 9 – 12, 2021 | Sep 9 – 12, 2021 | Classical | 39 | 1956 | 72 |
26. 4NCL Congress 2021 Leamington Spa ENG· Sep 10 – 12, 2021 | Sep 10 – 12, 2021 | Classical | 36 | 1956 | 30 |
City of Dublin Masters Dublin IRL· Sep 10 – 12, 2021 | Sep 10 – 12, 2021 | Classical | 21 | 2026 | 54 |
Tolstoy Mem 2021 Yasnaya Polyana RUS· Sep 11 – 12, 2021 | Sep 11 – 12, 2021 | Classical | 11 | 2706 | 54 |
| 26. 4NCL CongressWoodland Grange, Leamington Spa· Sep 10 – 12, 2021 | Sep 10 – 12, 2021 | Classical | 121 | 1876 | 205 |
Kurnosov Mem Rapid 2021 Chelyabinsk RUS· Sep 10 – 12, 2021 | Sep 10 – 12, 2021 | Rapid | 97 | 2355 | 166 |
I Casabermeja Open 2021 Casabermeja ESP· Sep 9 – 12, 2021 | Sep 9 – 12, 2021 | Classical | 45 | 1794 | 90 |
48. TCh-GRE 2021 Athens GRE· Sep 7 – 12, 2021 | Sep 7 – 12, 2021 | Classical | 165 | 1900 | 354 |
TCh-POL 2. League 2021 Sypniewo POL· Sep 4 – 12, 2021 | Sep 4 – 12, 2021 | Classical | 251 | 1989 | 882 |
TCh-POL 1. League 2021 Szklarska Poreba POL· Sep 4 – 12, 2021 | Sep 4 – 12, 2021 | Classical | 179 | 2207 | 703 |
| Asian University MenTornelo INT· Sep 10 – 12, 2021 | Sep 10 – 12, 2021 | Classical | 55 | 2039 | 228 |