| Country | Day | Month | Names |
 USA | 1 | May | Mae, May, Patience, Sigmund, Sigmunda |
| USA | 2 | May | Bing, Zoe, Zoey, Zolita |
| USA | 3 | May | Joletta, Trey, Troy, Viola, Violet, Violetta, Yolanda |
| USA | 4 | May | Mona, Monica, Monika, Monique, Monita, Web, Webb, Webster |
| USA | 5 | May | Jodi, Jodie, Jody, Judie, Judith, Judy, Terrell, Tyrell, Tyrese, Tyron, Tyrone, Tyrrell, Tyson |
| USA | 6 | May | Morna, Mya, Myah, Myrna, Orson, Prudence |
| USA | 7 | May | Ahern, Cooper, Dexter, Gisela, Gisella, Giselle, Gisselle, Hearne, Herne, Heron |
| USA | 8 | May | Acacia, Ace, Hal, Harold, Harriet, Harris, Harrison, Harry, Hattie |
| USA | 9 | May | Casandra, Cassandra, Grizelda, Kasandra, Kassandra, Zelda |
| USA | 10 | May | Cormac, Cormick, Gordon, Job, Joby, Jobina, Max, Maximilian, Maximus, Maxine, Maxwell |
| USA | 11 | May | Asa, Ervin, Erwin, Irvin, Irving, Irwing, Marlo, Marlon, Marlow, Marvin, Merle, Merlin, Mervin |
| USA | 12 | May | Achilla, Achilles, Grady, Grant, Kelby, Kellen |
| USA | 13 | May | Imani, Imelda, Imogene, Payton, Peyton |
| USA | 14 | May | Asher, Ashlee, Ashleigh, Ashley, Ashlie, Ashlyn, Ashlynn, Ashton, Berk, Berkeley, Bourke, Burgess, Burke |
| USA | 15 | May | Sofia, Sonia, Sonya, Sophia, Sophie, Ward, Wardell |
| USA | 16 | May | Brand, Branden, Brandi, Brandon, Brandy, Brannon, Brant, Brenda, Brendan, Brenden, Brendon, Brenna, Brennan, Brent, Brenton |
| USA | 17 | May | Pascal, Pascha, Pascual, Turner |
| USA | 18 | May | Aric, Eric, Erica, Erich, Erick, Ericka, Erik, Erika, Perry |
| USA | 19 | May | Dumont, Duncan, Dunstan, Indigo, Ivar, Ives, Wright, Yves |
| USA | 20 | May | Bernadette, Bernardina, Bernardine, Bernetta, Bernita |
| USA | 21 | May | Adelric, Adiel, Audric, Keaton, Kendrick |
| USA | 22 | May | Jolee, Joleen, Jolene, Jolie, Marshall |
| USA | 23 | May | Allard, Desirae, Desire, Desiree |
| USA | 24 | May | Chelsea, Chelsey, Chelsie, Landen, Landon |
| USA | 25 | May | Madalyn, Madeleine, Madeline, Madelyn, Madilyn, Marlee, Marleen, Marlena, Marlene, Marley |
| USA | 26 | May | Felipe, Flip, Phil, Philip, Philippa, Phillip |
| USA | 27 | May | Broderick, Brodie, Brody, Isador, Isadora, Isadore, Isidro |
| USA | 28 | May | Bevan, Bevis, Emil, Emiliano, Emilio, Faron, Ferrin, Ferron |
| USA | 29 | May | Duana, Duane, Duanna, Dwayne, Fitz, Fitzerald |
| USA | 30 | May | Joan, Joani, Joann, Joanna, Joanne, Johanna, Fawn, Fern, Fernanda, Fernando, Ferdinand, Ferdinanda, Ferdinando |
| USA | 31 | May | Camila, Camilla, Camille, Petra, Petronella, Pier |
