Teo's name day is celebrated on November 9th, specifically in the countries of Estonia and Finland.
Teo is a widely utilized masculine name globally, commonly serving as a short form for names such as Theodore or Mateo. In the USA, it maintains a moderate presence, appreciated for its simplicity and connection to Romance language cultures. Derived from Greek roots meaning "god" or "gift of God," the name carries a powerful divine origin. Historically, its use across ancient civilizations as a thematic element cemented its longevity. The name projects an elegant, strong, and modern mood, appealing widely due to its sophisticated flair. Firmly classified as male, Teo is an internationally recognized and concise choice.
| Country | Day | Month | Names |
 Romania | 4 | January | Teoctist |
| Romania | 5 | January | Sinclitichia, Teona, Teotempt |
 Ukraine | 5 | January | Apollinaria, Teon |
 Bulgaria | 6 | January | Bogomil, Bogdan, Bogdana, Bozhidar, Bozhidara, Borislav, Borislava, Jordan, Yordan, Yordanka, Nayden, Teodosii |
 Lithuania | 8 | January | Apolinaras, Ginte, Teofilis, Vilintas |
| Bulgaria | 11 | January | Bogdan, Bogdana, Bogomil, Bogomila, Teodosii |
| Romania | 11 | January | Teodosie |
 Spain | 25 | January | Elvira, Paula, Timoteo |
 Italy | 27 | January | Timoteo, Tito |
| Ukraine | 6 | February | Teofil, Teofila |
| Italy | 8 | February | Teodoro |
| Romania | 8 | February | Teodor, Zaharia |
| Romania | 11 | February | Teodora, Vlasie |
| Romania | 17 | February | Teodor |
 Poland | 21 | February | Eleonora, Feliks, Fortunat, Kiejstut, Teodor, Wyszeniega |
 USA | 24 | February | Maddison, Madison, Madisyn, Madyson, Mateo, Mathew, Mathias, Matt, Mattea, Matthew, Matthias, Mattias, Mattie, Matty, Modesto |
 Croatia | 27 | February | Roman, Teofil, Bogoljub |
| Romania | 2 | March | Nicolae, Teodot |
| Romania | 4 | March | Gherasim, Teodor |
| Bulgaria | 7 | March | Bozhan, Bozhidar, Bozhidara, Bozhil, Bozhko, Emanuil, Manol, Mancho, Teodor, Teodora, Toto, Todor, Teodor, Todora, Dora, Bogdan, Bogdana |
| Romania | 8 | March | Teofilact |
| Romania | 12 | March | Simeon, Teofan |
| Lithuania | 13 | March | Kristina, Liutauras, Teodora, Vaidile |
| Italy | 26 | March | Emanuele, Teodoro |
| Poland | 26 | March | Emanuel, Feliks, Larysa, Manuela, Nikifor, Teodor, Tworzymir |
| Croatia | 1 | April | Hugo, Teodora |
 Latvia | 1 | April | Dagne, Dagnis, Tautmilis, Teodora, Teofils |
| Lithuania | 1 | April | Dainora, Rimgaudas, Teodora |
| Poland | 1 | April | Chryzant, Grażyna, Hugo, Hugon, Katarzyna, Teodora, Tolisław, Zbigniew, Zbyszko |
| Romania | 5 | April | Agatopod, Teodul |
 Greece | 10 | April | Eteoklis, Hercules, Homer, Timothy, Dionisis, Pericles, Sofocles |
| Poland | 20 | April | Agnieszka, Amalia, Czech, Czechasz, Czechoń, Czesław, Florencjusz, Florenty, Nawoj, Sulpicjusz, Szymon, Teodor |
| Romania | 20 | April | Teotim |
| Poland | 22 | April | Heliodor, Kajus, Leonia, Leonid, Łukasz, Soter, Strzeżymir, Teodor |
| Romania | 22 | April | Teodor |
| Spain | 22 | April | Teodoro, Alexander, Apeles |
| Poland | 27 | April | Anastazy, Andrzej, Bożebor, Kanizjusz, Martyn, Piotr, Teofil, Zyta |
| Spain | 29 | April | Teodora, Karen, Katia, Wilfredo, Catalina |
| Spain | 1 | May | Berta, Tamar, Tamara, Oroncio, Andeoro, Teodardo, Paciencia |
| Spain | 3 | May | Juvenal, Violeta, Evencio, Teódulo, Alejandro, Estela, Felipe |
| Poland | 5 | May | Irena, Ita, Pius, Teodor, Waldemar, Zdzibor |
| Romania | 16 | May | Natan, Paisie, Sila, Teodor |
| Romania | 18 | May | Teodot |
| Croatia | 19 | May | Celestin V. p., Rajko, Teofil, Inka |
| Poland | 20 | May | Anastazy, Asteriusz, Bazyli, Bazylid, Bazylis, Bernardyn, Bernardyna, Bronimir, Iwo, Sawa, Teodor, Wiktoria |
| Poland | 29 | May | Bogusława, Maksymilian, Maria Magdalena, Teodor, Teodozja |
| Romania | 29 | May | Teodosia |
| Spain | 29 | May | Alejandro, Justo, Teodosia |
| Poland | 31 | May | Aniela, Bożysława, Ernesta, Ernestyna, Feliks, Petronela, Petronia, Petroniusz, Teodor |
| Spain | 5 | June | Eloisa, Marcia, Igor, Valeria, Nicanor, Doroteo, Bonifacio |
| Romania | 7 | June | Teodot |
| Romania | 8 | June | Teodor |
| Poland | 11 | June | Anastazy, Barnaba, Feliks, Radomił, Teodozja |
| Romania | 18 | June | Ipatie, Leontie, Teodul |
| Poland | 21 | June | Albaniusz, Alicja, Alojza, Alojzy, Demetria, Domamir, Marta, Rudolf, Rudolfa, Rudolfina, Teodor |
| Latvia | 1 | July | Imants, Ingars, Intars, Teobalds |
| Poland | 1 | July | Aaron, Bogusław, Halina, Klarysa, Marian, Niegosława, Teobald |
| Spain | 2 | July | Visitación, Martiniano, Vidal, Teodorico, Teobaldo |
| Lithuania | 4 | July | Gedgaile, Malvina, Skalvis, Teodoras |
| Poland | 4 | July | Ageusz, Alfred, Aurelian, Elżbieta, Innocenta, Innocenty, Józef, Julian, Malwin, Malwina, Odo, Teodor, Wielisław |
| Spain | 22 | July | Teófila, Zoraida, Magdalena, Zaida, Primitiva |
| Romania | 7 | August | Teodora |
| Poland | 27 | August | Angel, Angelus, Cezary, Gebhard, Józef, Kalasanty, Małgorzata, Przybymir, Rufus, Teodor |
 Hungary | 11 | September | Teodóra |
| Romania | 11 | September | Eufrosin, Teodora |
| Poland | 17 | September | Ariadna, Dezyderiusz, Drogosław, Franciszek, Hildegarda, Justyn, Justyna, Lambert, Lamberta, Narcyz, Teodora |
| Poland | 19 | September | Alfons, Alfonsyna, January, Konstancja, Sydonia, Teodor, Więcemir |
| Romania | 20 | September | Agapie, Eustatie, Teopist, Teopista |
| Italy | 21 | September | Matteo |
| Spain | 21 | September | Mateo, Mauricio |
| Romania | 22 | September | Teodosie |
| Poland | 24 | September | Gerard, Gerarda, Gerhard, Maria, Teodor, Tomir, Uniegost |
| Ukraine | 29 | September | Teofan |
| Poland | 2 | October | Dionizy, Leodegar, Stanimir, Teofil, Trofim |
| Croatia | 13 | October | Edvard kr., Edo, Teofil |
| Poland | 13 | October | Daniel, Edward, Gerald, Geraldyna, Maurycy, Mikołaj, Siemisław, Teofil |
 Czechia | 23 | October | Teodor |
| Poland | 23 | October | Iga, Ignacja, Ignacy, Jan, Marlena, Odilla, Roman, Seweryn, Teodor, Włościsław, Żegota |
| Poland | 25 | October | Bończa, Bonifacy, Chryzant, Daria, Inga, Kryspin, Maur, Sambor, Taras, Teodozjusz, Wilhelmina |
| USA | 27 | October | Cale, Caleb, Feodor, Isaac, Isaak, Issac, Izaac, Kaleb, Ted, Teddy, Teodor, Theodora, Theodore |
| Poland | 29 | October | Euzebia, Franciszek, Longin, Longina, Lubogost, Narcyz, Teodor, Wioletta |
| Latvia | 9 | November | Teodors |
| Lithuania | 9 | November | Dargintas, Estela, Skirtaute, Teodoras |
 Norway | 9 | November | Teodor, Tordis |
| Poland | 9 | November | Bogudar, Genowefa, Nestor, Teodor, Ursyn |
 Slovakia | 9 | November | Teodor |
| Spain | 9 | November | Teodoro |
 Sweden | 9 | November | Teodor, Teodora |
| Poland | 11 | November | Anastazja, Bartłomiej, Maciej, Marcin, Prot, Spycisław, Teodor |
| Spain | 14 | November | Teodoto, Clemente |
| Hungary | 20 | December | Teofil |
| Lithuania | 20 | December | Daugardas, Grazvile, Teofilis |
| Poland | 20 | December | Amon, Bogumiła, Dominik, Liberat, Teofil |
| Spain | 27 | December | Teófanos |
| Poland | 28 | December | Antoni, Dobrowiest, Emma, Godzisław, Teofila |
| Lithuania | 29 | December | Gaja, Gentvainas, Teofile |
Estonia 
Finland