The name Udo is commemorated with two separate name day observances in Europe. Name days for Udo occur on April 12th in Estonia and on October 3rd in Austria.
The name Udo is rooted in ancient Germanic languages, deriving from an element signifying wealth or inherited prosperity. Though extremely uncommon in the USA, its history in North America is tied to European immigration. Globally, Udo is identified as a concise and exclusively masculine name. It conveys a mood characterized by traditional strength, reliability, and European sophistication. This short name’s antique origin gives it a timeless quality, appealing to those seeking a sturdy and powerful appellation.
| Country | Day | Month | Names |
 Poland | 20 | February | Euchariusz, Eustachiusz, Eustachy, Leon, Ludmiła, Ludomiła, Ostap, Siestrzewit |
| Poland | 1 | March | Albin, Antoni, Antonina, Budzisław, Budzisz, Eudokia, Eudoksja, Ewdokia, Feliks, Herakles, Herkules, Jewdocha, Joanna, Józef, Nikifor, Piotr |
 Spain | 1 | March | Federico, Rosendo, Eudoxia, Eudoxio |
 Estonia | 7 | March | Rudolf, Ruudi, Ruut, Ralf, Rolf, Raul |
 Norway | 27 | March | Rudi, Rudolf |
 Sweden | 27 | March | Ralf, Rudolf |
 Austria | 29 | March | Berthold, Helmut, Ludolf |
| Austria | 17 | April | Eberhard, Rudolph |
 Croatia | 17 | April | Rudolf, Robert |
 Czechia | 17 | April | Rudolf |
 Hungary | 17 | April | Rudolf |
 Latvia | 17 | April | Rudis, Rudolfs, Viviana |
| Poland | 17 | April | Anicet, Innocenta, Innocenty, Jakub, Józef, Klara, Radociech, Robert, Roberta, Rudolf, Rudolfa, Rudolfina, Stefan |
 Slovakia | 17 | April | Rudolf |
| Poland | 7 | May | Benedykt, Bogumir, Domicela, Flawia, Florian, Gizela, Gustawa, Ludmiła, Ludomiła, Sawa, Wincenta |
| Latvia | 27 | May | Dzidra, Gunita, Henrijs, Ludolfs |
| Poland | 21 | June | Albaniusz, Alicja, Alojza, Alojzy, Demetria, Domamir, Marta, Rudolf, Rudolfa, Rudolfina, Teodor |
| Poland | 27 | July | Alfons, Alfonsyna, Aureli, Julia, Laurenty, Lilla, Marta, Natalia, Natalis, Pantaleon, Rudolf, Rudolfa, Rudolfina, Wszebor |
| Poland | 31 | July | Beatus, Demokryt, Emilian, Ernesta, Ernestyna, Helena, Iga, Ignacja, Ignacy, Justyn, Ludomir, Żegota |
 Italy | 25 | August | Ludovico, Vincenzo |
| Slovakia | 25 | August | Ľudovít |
| Spain | 5 | September | Eudosio |
| Slovakia | 14 | September | Ľudomil |
 France | 17 | October | Baudoin, Solène |
 USA | 17 | October | Brad, Braden, Bradford, Bradley, Brady, Braeden, Brayden, Braydon, Rodolfo, Rudi, Rudolf, Rudolph, Rudolphine, Rudy |
| Poland | 2 | November | Ambroży, Bohdana, Bożydar, Eudoksjusz, Małgorzata, Stojmir, Tobiasz, Wiktoryn |
| Austria | 6 | November | Christine, Leonhard, Rudolf |
| Estonia | 9 | November | Teo, Teodor, Tuudor |
| Poland | 10 | November | Andrzej, Lena, Leon, Ludomir, Nelly, Nimfa, Probus, Stefan |
 Denmark | 9 | December | Rudolph |