Semifinal 3
mercredi 8 août 2018, 19h19 GMT – 19h19 GMT
| Nom | Équipe | Temps | |
|---|---|---|---|
| 1 |  Anna Ryzhykova | Ukraine | 54.82″ |
| 2 |  Yadisleidis Pedroso | Italy | + 0.31″ |
| 3 | Meghan Beesley | Great Britain | + 0.39″ |
| 4 | Vera Rudakova | Authorised Neutral Athlete | + 0.42″ |
| 5 | Zuzana Hejnová | Czech Republic | + 1.21″ |
| 6 |  Yasmin Giger | Switzerland | + 1.99″ |
| 7 | Sara Gallego | Spain | + 2.43″ |
| Margo Van Puyvelde | Belgium | DNS |