A Spanish Phrase for Asking About Someone's Birthday: "¿Cuándo es tu cumpleaños?"

"¿Cuándo es tu cumpleaños?" means "When is your birthday?" and it's the basic Spanish expression used to ask someone when their birthday is. It's a handy conversation starter. To answer, you can say something like "Mi cumpleaños es en mayo." (My birthday is in May). To wish someone well, say "¡Feliz cumpleaños!" (Happy birthday!).