Mia's name day is observed on July 13 in Norway and on September 29 in the USA.
Mia is a universally loved feminine name that has achieved top-tier popularity globally, particularly throughout the USA and Europe. Historically a short form of Maria, the name is often interpreted as the possessive pronoun "mine" in Italian and Spanish. Its history shows a rapid shift from nickname to dominant standalone choice in the 20th and 21st centuries. The name is exclusively female and conveys a sophisticated yet playful mood. Its brevity and sharp sound contribute to its elegant and modern tone, making it highly appealing across cultures. Mia successfully merges deep traditional roots with contemporary flair.
| Country | Day | Month | Names |
 Poland | 19 | January | Andrzej, Bernard, Erwin, Erwina, Eufemia, Henryk, Kanut, Mariusz, Marta, Matylda, Mechtylda, Pia, Racimir, Sara |
 Bulgaria | 20 | January | Eftim, Efimir, Evtim, Evtimiya, Evtimia, Momchil |
 Greece | 29 | January | Varsamia |
 Spain | 16 | February | Elías, Samuel, Isaías, Jeremías |
 USA | 16 | February | Cliff, Clifford, Clifton, Jeremiah, Jeremy, Sonnie, Sonny, Sunny |
| Spain | 21 | February | Irene, Pedro Damián |
 Italy | 22 | February | Pier Damiani |
| Poland | 23 | February | Bądzimir, Damian, Florentyn, Łazarz, Piotr, Roma, Romana, Seweryn |
 Austria | 5 | March | Dietmar, Jeremia, Olivia |
| Poland | 20 | March | Aleksander, Aleksandra, Ambroży, Anatol, Bogusław, Cyriaka, Eufemia, Klaudia, Patrycjusz, Ruprecht, Wasyl, Wincenty |
| Spain | 12 | April | Andrés, Damián, Julio, Zenón |
| Austria | 15 | April | Anastasia, Damian, Una |
| Poland | 1 | May | Aniela, Filip, Jakub, Jeremi, Jeremiasz, Józef, Lubomir |
 Romania | 1 | May | Ieremia |
 Ukraine | 1 | May | Jeremiah, Jeremy, Tamara |
| Spain | 2 | May | Germán, Araceli, Atanasio, Vindemial, Exuperio, Zoé, Mafalda |
| Poland | 14 | May | Bończa, Bonifacy, Dobiesław, Jeremi, Jeremiasz, Wiktor, Wiktoriusz |
 Denmark | 7 | June | Jeremias |
| Bulgaria | 17 | June | Asparuh, Krum, Asen, Chavdar, Rumiana, Rumen, Momchil, Desislava |
 Finland | 26 | June | Jarmo, Jorma, Jarkko, Jarno, Jere, Jeremias |
| Poland | 26 | June | Jan, Jeremi, Jeremiasz, Paweł, Zdziwoj |
| Greece | 1 | July | Kosmas, Damianos, Damian |
| Romania | 1 | July | Cosma, Damian, Leontie |
| Romania | 11 | July | Eufimia |
| Poland | 14 | July | Bonawentura, Damian, Dobrogost, Franciszek, Izabela, Kosma, Marceli, Marcelin, Marcelina, Stella, Ulrych, Ulryk, Ulryka |
| USA | 14 | August | Anahi, Athena, Tamara, Tamia, Tammie, Tammy, Tara, Taryn, Terra |
| Poland | 3 | September | Antoni, Bartłomiej, Bazylissa, Bronisław, Bronisz, Erazma, Eufemia, Eufrozyna, Izabela, Jan, Joachim, Joachima, Manswet, Mojmir, Szymon, Wincenty, Zenon, Zenona |
| Denmark | 16 | September | Euphemia |
 Germany | 16 | September | Cornelius, Euphemia |
| Poland | 16 | September | Antym, Cyprian, Edda, Edyta, Eufemia, Eugenia, Franciszek, Jakobina, Kamila, Kornel, Lucja, Łucja, Sebastiana, Sędzisław, Wiktor, Wiktoriusz |
| Romania | 16 | September | Eufimia |
| Austria | 26 | September | Cosima, Damian, Kosmas |
| Italy | 26 | September | Cosma, Damiano |
| Spain | 26 | September | Cosme, Damián |
| Poland | 27 | September | Amadeusz, Amedeusz, Damian, Kosma, Przedbor, Urban |
| USA | 27 | September | Cosima, Cosimo, Cosmo, Damian, Damiana, Damien, Damion, Damon |
| Spain | 20 | October | Academia, Irene |
| Greece | 1 | November | Kosmas, Damianos, Anargiros, David |
| Romania | 1 | November | Cosma, Damian |
| Poland | 14 | November | Aga, Agata, Damian, Elżbieta, Emil, Emiliusz, Jozafat, Józef, Judyta, Kosma, Laurenty, Lewin, Ścibor, Ścibora, Serafin, Wszerad |
Norway