Ille celebrates its name day on September 17 in Estonia.
The name Ille is a highly infrequent, feminine given name rooted in Northern European linguistic traditions, likely derived as a short form for longer names associated with beauty or nobility. In the USA, its history is virtually non-existent outside of recent immigrant communities, maintaining its exotic rarity. The name carries an exceptionally soft and understated mood, suggesting an elegant and calm personality. Its gender classification is definitively female globally. This concise name offers a unique blend of historical depth and modern simplicity.
| Country | Day | Month | Names |
 USA | 7 | January | Alda, Aldea, Alden, Aldo, Aldric, Canute, Knut, Knute, Millard, Miller |
 Spain | 11 | January | Alejandro, Guillermo, Hortensia, Higinia, Higinio, Modesto |
| USA | 14 | January | Alair, Felice, Felicia, Felicity, Felix, Hilary, Hillary, Hillery |
| Spain | 10 | February | Guillermo, Amancio, Arnaldo, Arnau, Ecolástica |
| USA | 23 | February | Boswell, Gloria, Gloriana, Glory, Reilley, Riley, Rylan, Rylee, Ryleigh, Ryley, Rylie |
 France | 18 | March | Cyrille |
 Estonia | 30 | March | Pille, Sibülle |
| Estonia | 6 | April | Villem, Ville, Villi, Villo, Villu |
 Finland | 6 | April | Ville, Vilho, Viljami, Jami, Vilhelm, Vili |
 Greece | 24 | April | Elizabeth, Lisa, Anastasios, Doukas, Achilles, Orthodox Easter |
| France | 7 | May | Domitille, Gisèle |
| France | 12 | May | Achille |
| USA | 12 | May | Achilla, Achilles, Grady, Grant, Kelby, Kellen |
| Estonia | 20 | May | Liilia, Lilian, Liili, Lille, Lilli, Lilja |
| France | 31 | May | Pétronille |
 Norway | 31 | May | Pernille, Preben |
| USA | 31 | May | Camila, Camilla, Camille, Petra, Petronella, Pier |
| Spain | 25 | June | Salomón, Guillermo |
| USA | 25 | June | Bill, Billie, Billy, Guillermo, Liam, Mina, Minnie, Prosper, Velma, Vilma, Wilhelmina, Will, William, Willie, Willis, Wilma, Wilson |
 Denmark | 7 | July | Henrik, Villebaldus |
| France | 14 | July | Camille |
 Hungary | 20 | July | Illés |
| France | 22 | July | Madeleine, Wandrille |
| USA | 6 | August | Adriel, Araceli, Falco, Falcon, Itzel, Lucia, Lucille, Lucine, Lucy, Luz |
| France | 1 | September | Gilles, Jossué |
| Denmark | 11 | September | Hillebert |
| Finland | 16 | September | Hilla, Hellevi, Hille, Hillevi |
| France | 3 | October | Gérard, Sybille |
 Sweden | 15 | October | Hedvig, Hillevi |
| Hungary | 2 | November | Achilles |
| France | 6 | November | Bertille, Léonard |
 Poland | 7 | November | Achilles, Antoni, Engelbert, Florentyn, Melchior, Przemił |
 Austria | 8 | November | Gottfried, Willehad |
| Sweden | 18 | November | Lillemor, Moa |
| Estonia | 22 | November | Cecilia, Säsil, Silja, Silje, Sille |
| USA | 17 | December | Eleazar, Lazar, Lazaro, Lazarus, Olympia, Orval, Orville, Storm, Stormie, Stormy, Wilbert, Wilberta, Wilbur |