Semifinal 1
mercredi 8 août 2018, 18h17 GMT – 18h17 GMT
| Nom | Équipe | Temps | |
|---|---|---|---|
| 1 |  László Cseh | Hungary | 51.65″ |
| 2 |  James Guy | Great Britain | + 0.13″ |
| 3 | Egor Kuimov | Russia | + 0.3″ |
| 4 | Joeri Verlinden | Netherlands | + 0.51″ |
| 5 |  Yauhen Tsurkin | Belarus | + 0.56″ |
| 6 |  Marius Kusch | Germany | + 0.58″ |
| 7 | Liubomyr Lemeshko | Ukraine | + 0.69″ |
| 8 |  Jan Switkowski | Poland | + 1.58″ |