400m U18 Men, Heat:1 of 2 ; Official result since 12:04
CBP 49.70 Christopher O'Donnell
| Rank | Lane | ID | Name | PB | Team | Cat | Result | Info | Video |
| 1 | 2 | 395 | NUGENT Ciaran | Carraig-Na-Bhfear A.C. | 52.46 | Q | |||
| 2 | 6 | 394 | PENDER Jack | Carrick-on-Suir A.C. | 52.88 | Q | |||
| 3 | 5 | 643 | HUGHES Adam | Ballydrain Harriers | 53.00 | Q | |||
| 4 | 8 | 556 | CHINAKA Leon | Fingallians A.C. | 53.15 | ||||
| 5 | 4 | 716 | LENNON Marcus | Greystones & District A.C. | 53.91 | ||||
| 6 | 3 | 641 | MCGRATTAN Matthew | East Down AC | 54.00 | ||||
| 7 | 1 | 214 | HERITY Conor | North Sligo A.C. | 54.29 | ||||
| 8 | 7 | 878 | O'CONNOR Eoin | Kildare A.C. | 55.74 |