Per's name day is celebrated on June 29th in Norway and August 1st in Sweden.
Per is an uncommon given name in the United States, mostly seen through Scandinavian heritage, carrying connotations of classical European style. Etymologically, it derives from Peter, referencing the concept of 'rock' or 'stone'. The name projects a mood that is simple, traditional, and sturdy, suggesting reliability. Gender classification worldwide firmly identifies Per as a male name. It does not generally feature in contemporary mainstream American naming trends. Its usage remains largely tied to cultural lineage.
| Country | Day | Month | Names |
 Poland | 6 | January | Andrzej, Balcer, Baltazar, Bolemir, Epifania, Kacper, Kasper, Melchior |
 Sweden | 6 | January | Baltsar, Kasper, Melker |
 USA | 22 | January | Enoch, Piper, Vicenta, Vicente, Vince, Vincent, Vincentia, Vincenzo, Vinnie |
 Slovakia | 12 | February | Perla |
 Austria | 7 | March | Felicitas, Perpetua, Reinhard |
 Croatia | 7 | March | Perpetua, Felicita, Ardo |
 Denmark | 7 | March | Perpetua |
 Italy | 8 | March | Perpetua |
| Croatia | 27 | March | Ivan Damašć., Rupert, Lidija, Lada |
| Italy | 27 | March | Ruperto |
| Poland | 27 | March | Benedykt, Ernest, Ernestyn, Jan, Lidia, Rościmir, Rupert |
 Spain | 27 | March | Ruperto, Lilia, Alejandro |
| Spain | 28 | March | Esperanza, Gundelina |
| USA | 29 | March | Berthold, Fletcher, Pearl, Pearle, Pearlie, Pearline, Perla |
 Greece | 10 | April | Eteoklis, Hercules, Homer, Timothy, Dionisis, Pericles, Sofocles |
| Spain | 18 | April | Perfecto |
 Finland | 24 | April | Pertti, Albert, Altti |
| Austria | 26 | April | Helene, Trudpert |
| Spain | 2 | May | Germán, Araceli, Atanasio, Vindemial, Exuperio, Zoé, Mafalda |
| USA | 7 | May | Ahern, Cooper, Dexter, Gisela, Gisella, Giselle, Gisselle, Hearne, Herne, Heron |
 Norway | 9 | May | Jesper, Kasper |
 Estonia | 12 | May | Vootele, Võitur, Tapper, Rünno |
| Austria | 15 | May | Hertraud, Rupert, Sonja, Sophie |
| Spain | 18 | May | Alejandra, Félix, Próspero |
| USA | 18 | May | Aric, Eric, Erica, Erich, Erick, Ericka, Erik, Erika, Perry |
| Norway | 31 | May | Pernille, Preben |
| Sweden | 31 | May | Pernilla, Petronella |
| Poland | 23 | June | Agrypina, Albin, Bazyli, Józef, Piotr, Prosper, Wanda, Zenon, Zenona |
| Denmark | 25 | June | Prosper |
 France | 25 | June | Aliénor, Eléonore, Prosper, Salomon |
| USA | 25 | June | Bill, Billie, Billy, Guillermo, Liam, Mina, Minnie, Prosper, Velma, Vilma, Wilhelmina, Will, William, Willie, Willis, Wilma, Wilson |
| Spain | 7 | July | Fermín, Roberto, Odón, Germano, Peregrino |
 Latvia | 13 | July | Alda, Margarita, Margrieta, Mariska, Perle |
| Sweden | 26 | July | Jesper |
| USA | 1 | August | Charissa, Charity, Chasity, Cheri, Cherie, Cherry, Cheryl, Esperanza, Faith, Faye, Hope, Nadia, Nadine |
| Finland | 24 | August | Perttu, Bertta |
| USA | 26 | August | Percival, Percy, Travis, Trevis, Trevon, Trevor |
| Latvia | 5 | September | Klaudija, Perse, Persijs, Vaida |
| Croatia | 18 | September | Ivan Macias, J. Kupert., Irena |
| Austria | 24 | September | Gerhard, Hermann, Rupert, Virgil |
| Estonia | 20 | October | Kaspar, Kasper, Jasper |
| Finland | 20 | October | Kasperi, Kauno, Jasper, Jesper, Kasper |
| Austria | 1 | November | Arthur, Harald, Otmar, Rupert |
| Austria | 3 | November | Hubert, Martin, Pirmin, Rupert |
| USA | 5 | November | Perdita, Tiara, Tiera, Tierra, Swain, Swana |
| Spain | 18 | December | Esperanza, Macarena |
| Croatia | 20 | December | Petar Kanizije, Perica |
| USA | 28 | December | Aspen, Caspar, Gaspar, Innocent, Jasper, Kasper, Woodrow, Woody |