I learned that "just in case" should be translated por si acaso, but I have also heard por si used by itself without the acaso. I believe I've even heard si acaso without the por. What is the difference? Is it just stylistic, or are the cases where you must use one or the other?

1 Answer 1


In principle, the three combinations have different meanings:

  • Por si acaso is an expression which adequately translates just in case.
  • Por si might be a shortening of por si acaso. Perhaps you heard por si las moscas, and couldn't make sense of it. That is a slang variation of por si acaso. A couple of examples where it is used as a shortening of por si acaso are:

    Voy a hacer (algo) por si (algo).

    Cerraré la puerta con llave por si hay ladrones merodeando.

    Ahorré dinero por si llegaba la crisis económica.

However, I believe this is not a correct use of the language, though it might be common in some places. It doesn't sound right to me, at least.

  • Similarly, si acaso sounds like a slang variation and not entirely correct (actually, it sounds worse than por si).

    Cerraré la puerta si acaso hay ladrones merodeando.

    Si acaso vienes a visitarme, cocinaré pavo para ti.

  • I noticed "Si Acaso Vuelves" is the name of a Vicente Fernandez song (and I'm pretty sure I've heard it in a different song as well).
    – jrdioko
    Feb 3, 2012 at 3:49
  • Si acaso is incorrect in this context. But it is correct in other contexts.
    – Jose Luis
    Feb 3, 2012 at 7:36

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.