Semifinal 3
mercredi 2 octobre 2019, 20h05 GMT – 20h05 GMT
| Nom | Équipe | Temps | |
|---|---|---|---|
| 1 |  Sydney McLaughlin | United States | 53.81″ |
| 2 |  Lea Sprunger | Switzerland | + 0.71″ |
| 3 | Shiann Salmon | Jamaica | + 1.35″ |
| 4 |  Yadisleidis Pedroso | Italy | + 1.59″ |
| 5 | Aminat Yusuf Jamal | Bahrain | + 1.73″ |
| 6 | Gianna Woodruff | Panama | + 1.8″ |
| 7 | Jessica Turner | Great Britain | + 2.06″ |
| 8 | Lauren Wells | Australia | + 2.13″ |