In Finland, the name day for Iro is April 5.
The name Iro is quite rare in the United States, making it distinctive and intriguing. Its origins are complex, with potential links to ancient Greek names like Hiero, meaning "sacred," or even having roots in some African languages with meanings related to "light" or "strength." This rarity contributes to a mood that feels both elegant and perhaps a touch mysterious, offering a sophisticated yet uncommon choice. While not strongly associated with a particular gender, it leans slightly towards a masculine feel due to some of its historical connections, though its uniqueness allows for broader interpretation. Overall, Iro presents an image of quiet confidence and individuality.
| Country | Day | Month | Names |
 Hungary | 18 | January | Piroska |
 Poland | 24 | January | Chwalibóg, Felicja, Mirogniew, Rafaela, Rafał, Tymoteusz |
 Croatia | 1 | February | Brigita, Gita, Miroslav |
 Italy | 9 | February | Girolamo Emiliani |
| Poland | 26 | February | Aleksander, Bogumił, Cezariusz, Dionizy, Mirosław, Nestor |
 Spain | 4 | March | Francisca, Arcadio, Casimiro, Eugenio |
 Bulgaria | 6 | March | Krasimir, Krasimira, Bella, Miroslav, Miroslava |
 Czechia | 6 | March | Miroslav |
| Spain | 11 | March | Ramiro, Oria |
 USA | 11 | March | Alberta, Albertina, Angus, Connie, Constance, Constantine, Consuela, Consuelo, Elberta, Ramiro |
| Spain | 13 | March | Patricia, Rodrigo, Ramiro |
| Spain | 24 | March | Delmiro, Edelmira, Edelmiro, Timolao |
 Slovakia | 29 | March | Miroslav |
| Czechia | 5 | April | Miroslava |
| Slovakia | 5 | April | Miroslava |
| Bulgaria | 5 | May | Irina, Mira, Irena, Miroslav, Miroslava |
| Bulgaria | 11 | May | Kiril, Kirila, Metodi, Kiro, Kirilka, Metodiy, Metodiya |
| Bulgaria | 24 | May | Kiril, Kirila, Metodi, Kiro, Kirilka, Metodiy, Metodiya |
| Spain | 16 | June | Ciro, Aquilino, Aureliano, Siro, Alina, Regina, Regis |
 Latvia | 19 | June | Nils, Vaironis, Viktors |
| Spain | 29 | June | Ciro, David, Siro, Paola, Pablo, Pedro |
| Slovakia | 3 | July | Miroslav |
| Croatia | 14 | July | Kamilo de Lellis, Miroslav |
| Spain | 14 | July | Camila, Vladimiro, Camilo |
| Poland | 26 | July | Anna, Bartolomea, Grażyna, Mirosława |
| Poland | 4 | August | Alfred, Arystarch, Dominik, Maria, Mironieg, Protazy |
 Greece | 17 | August | Miron, Straton |
| Poland | 17 | August | Anastazja, Angelika, Anita, Bertram, Eliza, Jacek, Jaczewoj, Joanna, Julianna, Liberat, Miron, Żanna, Zawisza |
| Poland | 30 | August | Adaukt, Częstowoj, Gaudencja, Miron, Rebeka, Róża, Szczęsna, Szczęsny, Tekla |
 Finland | 7 | September | Miro, Arho, Arhippa, Milo |
| Italy | 30 | September | Girolamo |
| Croatia | 20 | October | Vendelin, Irena, Miroslava |
| Greece | 1 | November | Kosmas, Damianos, Anargiros, David |
 Estonia | 3 | November | Kaido, Kaidu, Kairo, Kaivo, Kaimo, Kaimar |
| Poland | 19 | November | Elżbieta, Mironiega, Paweł, Seweryn, Seweryna |
| Italy | 9 | December | Siro |
| Bulgaria | 12 | December | Darina, Spiro, Spiridon |
| Greece | 12 | December | Spiros |
| Estonia | 19 | December | Maarius, Mario, Mairo |
| Finland | 19 | December | Iiro, Iisakki, Iikka, Isko |
