The men's 400 metres event at the 2019 European Athletics U23 Championships was held in Gävle, Sweden, at Gavlehof Stadium Park on 11, 12, and 13 July.[1]
| width=200 bgcolor=gold | Gold | width=200 bgcolor=silver | Silver | width=200 bgcolor=CC9966 | Bronze |
| Fabrisio Saïdy | Cameron Chalmers | Brayan Lopez |
Prior to the competition, the records were as follows:
| European U23 record | 44.33 | Rome, Italy | 3 September 1987 | ||
| Championship U23 record | 45.04 | Bydgoszcz, Poland | 19 July 2003 |
Qualification rule: First 3 (Q) and the next 4 fastest (q) qualified for the semifinals.
| Rank | Heat | Name | Nationality | Time | Notes | |
|---|---|---|---|---|---|---|
| 1 | 2 | 47.14 | Q | |||
| 2 | 4 | 47.16 | Q | |||
| 3 | 2 | 47.30 | Q | |||
| 4 | 2 | 47.31 | Q | |||
| 5 | 4 | 47.32 | Q | |||
| 6 | 1 | 47.33 | Q | |||
| 7 | 3 | 47.39 | Q | |||
| 8 | 4 | 47.48 | Q, | |||
| 9 | 3 | 47.50 | Q | |||
| 10 | 4 | 47.55 | q | |||
| 11 | 1 | 47.63 | Q | |||
| 12 | 4 | 47.67 | q | |||
| 13 | 1 | 47.67 | Q | |||
| 14 | 3 | 47.68 | Q, | |||
| 15 | 4 | 47.70 | q | |||
| 16 | 4 | 47.78 | q | |||
| 17 | 2 | 47.80 | ||||
| 18 | 2 | 47.84 | ||||
| 19 | 1 | 47.98 | ||||
| 20 | 1 | 47.93 | ||||
| 21 | 3 | 47.99 | ||||
| 22 | 2 | 48.04 | ||||
| 23 | 3 | 48.05 | ||||
| 24 | 2 | 48.07 | ||||
| 25 | 3 | 48.23 | ||||
| 26 | 3 | 48.49 | ||||
| 27 | 1 | 48.53 | ||||
| 28 | 4 | 48.65 | ||||
| 29 | 1 | 48.68 | ||||
| 30 | 1 | 49.24 | ||||
| 31 | 3 | 49.29 | ||||
| 32 | 2 | 49.85 |
Qualification: First 3 in each heat (Q) and next 2 fastest (q) qualified for the final.
| Rank | Heat | Name | Nationality | Time | Notes | ||
|---|---|---|---|---|---|---|---|
| 1 | 1 | align=left | 46.34 | Q | |||
| 2 | 2 | align=left | 46.34 | Q, PB | |||
| 3 | 2 | align=left | 46.39 | Q | |||
| 4 | 2 | align=left | 46.41 | Q, SB | |||
| 5 | 1 | align=left | 46.66 | Q | |||
| 6 | 2 | align=left | 46.91 | q | |||
| 7 | 1 | align=left | 47.02 | Q, PB | |||
| 8 | 1 | align=left | 47.03 | q | |||
| 9 | 1 | align=left | 47.17 | ||||
| 10 | 2 | align=left | 47.18 | ||||
| 11 | 1 | align=left | 47.34 | ||||
| 12 | 1 | align=left | 47.48 | ||||
| 13 | 2 | align=left | 47.48 | SB | |||
| 14 | 2 | align=left | 47.49 | SB | |||
| 15 | 2 | align=left | 48.18 | ||||
| 1 | align=left | R163.3(a)[2] |
| Rank | Lane | Name | Nationality | Time | Notes | |||
|---|---|---|---|---|---|---|---|---|
| 6 | align=left | align=left | 45.79 | EU23L, PB | ||||
| 5 | align=left | align=left | 45.92 | SB | ||||
| 3 | align=left | align=left | 46.16 | PB | ||||
| 4 | 7 | align=left | align=left | 46.52 | ||||
| 5 | 4 | align=left | align=left | 46.79 | ||||
| 6 | 8 | align=left | align=left | 47.01 | PB | |||
| 7 | 1 | align=left | align=left | 47.16 | ||||
| 8 | 2 | align=left | align=left | 47.32 |