How to Say "mail slot" in Spanish
The Spanish word for “mail slot” is “casillero” — B1 level.
English → SpanishB1
nounB1
pigeonhole for internal mail

Examples
Por favor, deja el reporte en mi casillero de la oficina.
Please leave the report in my office mail slot.
Tengo un casillero postal para recibir mis paquetes.
I have a P.O. Box to receive my packages.
Cada profesor tiene un casillero asignado en la sala de maestros.
Every teacher has an assigned mail slot in the teachers' lounge.
Using 'en'
To say something is 'in' the mail slot, always use 'en' (En el casillero).
Casillero vs. Casilla
Mistake: “Saying 'casillero' for a checkbox on a form.”
Correction: Use 'casilla' for a small square on a form or board game; 'casillero' is a physical 3D box or slot.
Related Translations
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