Semifinal 1
dimanche 21 juillet 2019, 13h12 GMT – 13h12 GMT
| Nom | Équipe | Temps | |
|---|---|---|---|
| 1 |  Marie Wattel | France | 57″ |
| 2 |  Emma McKeon | Australia | + 0.01″ |
| 3 | Brianna Throssell | Australia | + 0.02″ |
| 4 |  Elena Di Liddo | Italy | + 0.04″ |
| 5 |  Katie McLaughlin | United States | + 0.23″ |
| 6 |  Rebecca Smith | Canada | + 0.59″ |
| 7 |  Yufei Zhang | China | + 0.93″ |
| 8 | Hiroko Makino | Japan | + 1.49″ |