Por Favor...or just Favor.
Would you get away with just saying "favor" or does it always have to be "por favor".Seems a bit long winded for just "please" ...
5 Answers
Hmmm, I have heard "por favor" chopped down to "porfa" (even "porfas" if you're trying to sound "street")... used so nonchalantly & frequently that it appears to be evolving right before my ears... Southwestern USA & Northern México, in case you're wondering where this clipped phrase is becoming commonplace! 
Like Cristalina I have notice "porfa" as "street" talk but depending on how you want to be perceived it's hardly going to be of much practical use. I heard it in the 80s and 90s in Barcelona in the clubs and late night music venues.
In Traditional Spanish conversation I have never come across the dropping of ¨por¨ in ¨por favor¨. It isn´t done. It would be rude. It´s mostly used by foreigners anyway, Spaniards rarely use it.
You can use favor by itself like this:
¡Favor de entrar!
This means
Por favor, ¡entra!
You use just "favor" when you want to say that you need or want a favor. - Puedes hacer me un favor. For please, use "por favor".
