"Can I" and "may I" both come up "puedo"
but in English mean two different things even though they are frequently misused. I looked for a thread that might have already discussed this but with no luck. Is there really no distinction in Spanish - (other than asking for permission) for "may" as in "may I have the salt?"
6 Answers
Podría = could I, may I (much more polite)
Puedo = can I
can/may = Podría = used around the market and at the Spanish restaurant by my house. (grrrr now I want La Gradija ~ spanish restaurant in Florida)
Marianne was right, it can be used like this.
Spanish also uses pudiera which is supposed to be a polite way of saying May I.
When asking permission you could also use permitir (to allow).
May I enter?
¿Me permita que entre? 
I've not discussed this on SD before but I've certainly asked about it a few times and nobody was ever able to find a way round. So far as I know "can" and "may" are indivisible in Spanish.
A quick look at an online dictionary of etymology suggest that "can" comes via a more Northern origin, Norse or thereabouts while "may" is of simpler German origin. So it looks as if English, once again, has two virtually equivalent words of different origin which, over the course of time, have acquired rather different meanings.
May I have the salt? ¿Puedo tener la sal? May I and Can I have the same meaning in Spanish.
