| # | Name | Origin | Meaning | Gender | |
|---|---|---|---|---|---|
| 401 | Isla | Spanish | Variant of Isabel: Devoted to God. A Spanish variant of Elizabeth. | F | |
| 402 | Isobel | Spanish | Variant of Isabel: Devoted to God. A Spanish variant of Elizabeth. | F | |
| 403 | Itsaso | Spanish | Sea. | F | |
| 404 | Itxaro | Spanish | Hope. | F | |
| 405 | Ivette | Spanish | Variant of Yvette. | F | |
| 406 | Izar | Spanish | Star. | F | |
| 407 | Izarra | Spanish | Star. | F | |
| 408 | Izarre | Spanish | Star. | F | |
| 409 | Izazkun | Spanish | Reference to the Virgin Mary. | F | |
| 410 | Jacinta | Spanish | Hyacinth or purple. | F | |
| 411 | Jade | Spanish | Jewel. | F | |
| 412 | Jaime | Spanish | Pet form of James used as a woman's name. | F | |
| 413 | Jaione | Spanish | Reference to the Nativity. | F | |
| 414 | Jakinda | Spanish | Hyacinth. | F | |
| 415 | Jasone | Spanish | Assumption. | F | |
| 416 | Javiera | Spanish | Owns a new house. | F | |
| 417 | Jesusa | Spanish | Named for Jesus. | F | |
| 418 | Jimena | Spanish | Heard. | F | |
| 419 | Joaquina | Spanish | Prepared. | F | |
| 420 | Jordana | Spanish | Down flowing. The river in Palestine where Jesus was baptized has been used as a given name since the Crusades. | F | |