| Inocente | A name meaning free from all guilt. |
| Iratze | Reference to the Virgin Mary |
| Irene | Eace; Peace; Peaceful; A peaceful woman; in mythology, the goddess of peace; Peace. An early Christian martyr, and later borne by several Byzantine empresses. |
| Irune | Reference to the Holy Trinity |
| Isabel | Pledged to God in solemn devotion. |
| Isabela | Variant of Elizabeth. My God is bountiful:God of plenty. |
| Isabelita | from isabel meaning oath of god |
| Isabella | Variant of Elizabeth. My God is bountiful:God of plenty. |
| Isadoro | Gift of the goddess Isis. |
| Isamar | Perhaps an elision of "Isabel del Mar" |
| Isidora | Gifted with many ideas |
| Isidoro | Gifted with many ideas |
| Isidro | Gifted with many ideas |
| Isleta | Spanish for a little island. |
| Ismael | The Biblical Ishmael is the English language equivalent. A Prophet's name.; God listens. In the bible Ismael was son of Abraham by Sarah's Egyptian slave woman Hagar.; God Will Hear |
| Itsaso | Basque word meaning the ocean. |
| Itxaro | Basque name meaning to hope. |
| Ivan | A Slavic name meaning God is gracious. |
| Ivette | Variant of Yvette. |
| Ixidor | a gift of ideas |
| Izar | A name meaning star in Basque. |
| Izarra | A name meaning the star in Basque. |
| Izarre | A name meaning starlike beauty. |
| Izazkun | Reference to the Virgin Mary |
| Jacenta | Derived from the hyacinth flower. |
| Jacinta | Hyacinth or purple |
| Jacinto | Spanish for the hyacinth flower. |
| Jacobo | Spanish form of Jacob |
| Jade | Jewel. Courageous and adoring. |
| Jago | To wake up or stay awake. |
| Jaimica | A unique name meaning supplanter |
| Jaione | Reference to the Nativity |
| Jairo | Variant of the Hebrew Jairus Jehovah enlightens. |
| Jakinda | A name meaning a hyacinth flower. |
| Jasone | It means a healer or physician. |
| Javier | Bright. Variant of Xavier. |
| Javiera | Owns a new house |
| Javiero | Born in January |
| Jeraldo | Variant of Gerald Rules by the spear. |
| Jerardo | Variant of Gerard Rules by the spear. |