Buenas tardes vs. buenas noches

'Buenas noches' and 'buenas tardes' are two Spanish phrases commonly used to greet people at different times of the day. Understanding when to use each phrase correctly is important for appropriate social interactions in Spanish-speaking countries.

Buenas tardes

'Buenas tardes' translates to 'good afternoon' in English and is typically used as a greeting from around noon until the late afternoon or early evening hours, though the exact time can vary regionally.
Hola, buenas tardes, ¿cómo estás?
(Hello, good afternoon, how are you?)
Buenas tardes, señora García. ¿Puedo ayudarle en algo?
(Good afternoon, Mrs. García. Can I help you with anything?)
¿Ya comiste? Buenas tardes, por cierto.
(Have you eaten yet? Good afternoon, by the way.)

Buenas noches

'Buenas noches' means 'good evening' or 'good night' in English and is used as a greeting during the late evening and night hours. The phrase can also be used to say goodbye at the end of the evening or before going to bed.
Buenas noches, ¿podría decirme la hora?
(Good evening, could you tell me the time?)
¡Buenas noches a todos, que descansen!
(Good night everyone, have a restful sleep!)
Antes de irme a la cama siempre digo: buenas noches.
(Before going to bed I always say: good night.)

Summary

In summary, 'buenas tardes' is used as a greeting from noon until early evening while 'buenas noches' takes over in the late evening and at night. Both phrases are essential for daily courtesy in Spanish-speaking communities and can reflect cultural variations concerning the times they are used.