 | 400m femenino con 18 años |
| Tiempo | Nadador | Año | Localización |
| 04:07.59 | Carla Carrón Muiña | 2023 | CASTELLÓN |
| 04:08.39 | Carla Carrón Muiña | 2023 | FRIGSA |
| 04:13.03 | Carla Carrón Muiña | 2023 | ÁLVARO PINO |
| 04:13.19 | Carla Carrón Muiña | 2023 | FRIGSA |
| 04:14.34 | Carla Carrón Muiña | 2023 | CASTELLÓN |
| 04:18.14 | Carla Carrón Muiña | 2023 | RIAZOR |
| 04:34.62 | Laura Rodríguez Novoa | 2018 | BATALLONES |
| 04:35.97 | Carla Faro Martínez | 2021 | ÁLVARO PINO |
| 04:40.11 | Andrea D. Casabella | 2021 | AS POZAS |
| 04:40.82 | Andrea D. Casabella | 2021 | Álvaro Pino |
| 04:40.94 | Laura Rodríguez Novoa | 2018 | CARBALLO |
| 04:41.05 | Inés Borge Juste | 2024 | A FIEITEIRA |
| 04:41.58 | Andrea D. Casabella | 2021 | RÍAS DO SUR |
| 04:43.86 | Andrea D. Casabella | 2021 | ÁLVARO PINO |
| 04:46.51 | Andrea D. Casabella | 2021 | RÍAS DO SUR |
| 04:46.68 | Laura Rodríguez Novoa | 2018 | RCNV |
| 04:47.34 | Andrea D. Casabella | 2021 | ÁLVARO PINO |
| 04:51.59 | Andrea D. Casabella | 2021 | FLUVIAL |
| 04:56.69 | Andrea D. Casabella | 2021 | FLUVIAL |
| 05:01.25 | Naiara Eijo Gil | 2024 | AS POZAS |
| 05:29.30 | Laura Costa Fernández | 2019 | AS POZAS |
| 05:29.75 | Laura Costa Fernández | 2019 | A CAÑIZA |
| 05:29.75 | Laura Costa Fernández | 2019 | A CAÑIZA |
| 05:46.03 | Lorena Rodríguez Pérez | 2019 | AS POZAS |
| 05:46.10 | Lorena Rodríguez Pérez | 2019 | A CAÑIZA |
| 05:46.10 | Lorena Rodríguez Pérez | 2019 | A CAÑIZA |