Anu's name day is observed on July 26 in Estonia and on December 9 in Finland.
Anu is a concise name with global prominence, frequently encountered across India and Northern European nations like Finland. The name has complex origins, stemming both from Sanskrit concepts related to particles and ancient Mesopotamian mythology where Anu was the supreme sky deity. Due to these diverse roots, the name often functions as female in modern usage, though it was historically masculine. Anu possesses a mood that is classically simple, reliable, and subtly elegant. Its history reflects continuous usage across millennia in varied linguistic environments.
| Country | Day | Month | Names |
 Spain | 1 | January | Manuel, Emanuel, Jesús |
 Poland | 3 | January | Arletta, Dan, Danisz, Danuta, Enoch, Genowefa, Piotr, Włościsława |
 Estonia | 7 | January | Kanut, Nuut, Susi, Hirvo |
 USA | 7 | January | Alda, Aldea, Alden, Aldo, Aldric, Canute, Knut, Knute, Millard, Miller |
 Denmark | 9 | January | Julianus |
| Denmark | 19 | January | Pontianus |
| Poland | 19 | January | Andrzej, Bernard, Erwin, Erwina, Eufemia, Henryk, Kanut, Mariusz, Marta, Matylda, Mechtylda, Pia, Racimir, Sara |
 Austria | 20 | January | Fabianus, Sebastian, Ursula, Ute |
| Austria | 4 | February | Andreas, Rabanus, Veronika |
 Romania | 6 | February | Fotie, Ioan, Varsanufie, Vucol |
| Poland | 16 | February | Bernard, Dan, Danisz, Danuta, Julianna, Symeon |
| Denmark | 17 | February | Findanus |
| Poland | 2 | March | Absalon, Franciszek, Halszka, Helena, Henryk, Januaria, Krzysztof, Lew, Michał, Paweł, Piotr, Radosław, Symplicjusz |
| Denmark | 4 | March | Adrianus |
 Bulgaria | 7 | March | Bozhan, Bozhidar, Bozhidara, Bozhil, Bozhko, Emanuil, Manol, Mancho, Teodor, Teodora, Toto, Todor, Teodor, Todora, Dora, Bogdan, Bogdana |
| Spain | 25 | March | Abel, Gloria, Encarnación, Rebeca, Anunciación, Maite, Humberto |
 Croatia | 26 | March | Montan, Maksima, Emanuel |
 Czechia | 26 | March | Emanuel |
 Finland | 26 | March | Manu, Manne, Immanuel, Immo |
 Hungary | 26 | March | Emánuel |
 Italy | 26 | March | Emanuele, Teodoro |
 Latvia | 26 | March | Dabrelis, Eizenija, Emanuels, Zenija |
 Lithuania | 26 | March | Arbutas, Emanuelis, Feliksas, Tekle, Vydmante |
| Poland | 26 | March | Emanuel, Feliks, Larysa, Manuela, Nikifor, Teodor, Tworzymir |
 Slovakia | 26 | March | Emanuel |
 Sweden | 26 | March | Emanuel |
| Denmark | 8 | April | Janus |
| Latvia | 8 | April | Dana, Danute, Dziedra, Edgars, Zanete |
| Poland | 8 | April | Apolinary, Cezary, Cezaryna, Dionizy, Gawryła, January, Radosław, Sieciesława |
| Romania | 21 | April | Ianuarie |
| Poland | 4 | May | Florian, Grzegorz, January, Michał, Monika, Paulin, Strzeżywoj |
| Lithuania | 7 | May | Butautas, Danute, Rimte, Stanislovas, Stasys |
| Denmark | 10 | May | Gordianus |
| Denmark | 25 | May | Urbanus |
| Lithuania | 25 | May | Almantas, Danute, Urbonas |
| Lithuania | 12 | June | Anupras, Dove, Kristijonas, Kristis, Ramunas |
| Latvia | 15 | June | Banuta, Benno, Vilija, Zermena |
| Romania | 17 | June | Ismail, Manuil, Savel |
| Denmark | 21 | June | Albanus |
| Poland | 24 | June | Dan, Danisz, Danuta, Emilia, Jan, Wilhelm |
| Poland | 10 | July | Aleksander, Amelia, Aniela, Filip, January, Radziwoj, Rufina, Samson, Sylwan, Sylwana, Witalis |
| USA | 10 | July | Emanuel, Emmanuel, Gage, Immanuel, Manuel, Manuela |
| Poland | 17 | July | Aleksander, Aleksy, Andrzej, Bogdan, Dzierżykraj, Januaria, Julietta, Leon, Marceli, Marcelina, Maria Magdalena |
| Denmark | 31 | July | Germanus |
| Poland | 6 | August | Felicysym, Jakub, January, Sława, Stefan, Sykstus, Wincenty |
| Denmark | 9 | August | Romanus |
| Austria | 13 | August | Cassian, Hippolyt, Marko, Pontianus |
| Estonia | 19 | August | Magnus, Maanus, Maano, Mango, Mauno |
| Romania | 27 | August | Fanurie |
| Denmark | 13 | September | Cyprianus |
| Austria | 19 | September | Igor, Januarius |
| Croatia | 19 | September | Januarije, Emilija |
| Poland | 19 | September | Alfons, Alfonsyna, January, Konstancja, Sydonia, Teodor, Więcemir |
| Poland | 1 | October | Benigna, Cieszysław, Dan, Danisz, Danuta, Igor, Jan, Remigiusz |
| Czechia | 6 | October | Hanuš |
| Spain | 10 | October | Tomás de Villanueva |
| Denmark | 20 | October | Felicianus |
| Estonia | 22 | October | Ihan, Ihanus, Jaanus, Jaano, Hannus, Hanno, Annus, Anno, Delia |
 Norway | 30 | October | Aksel, Ove, Ånund |
| Finland | 11 | November | Panu |
| Denmark | 17 | November | Anianus |
| Poland | 21 | November | Albert, Alberta, Albertyna, Janusz, Konrad, Konrada, Maria, Piotr, Regina, Rena, Rufus, Twardosław, Wiesław |
| Bulgaria | 9 | December | Ana, Anica, Anelia, Anna, Yana, Aneta, Anushka, Nusha |
 France | 25 | December | Manuel |
 Greece | 26 | December | Manolis, Manuella, Emma, Panagiotis, Emmanuel |