As a native Spanish speaker, I would say we can understand most of written portuguese stuff, as well as Portuguese speakers can understand quite a bit of written Spanish. It's a bit more complicated to understand spoken language, but I've been told that Portuguese speakers can understand more spoken Spanish than we can understand them. I think it's because the pronunciation, since for me portuguese speakers have a very particular way of pronuncing the words. At least this is what happens for me with argentinian Spanish (I'm from Argentina) and brazilian Portuguese. Maybe between people from Spain and Portugal it is easier to communicate, as Andres has pointed out.

I'm brazilian native speaker, and I learned the basic on Spanish language. These languages can be considered very close, although there is a lot of vocabulary differences. There is also false friends, words that are similar and have different meanings. As said before, to understand written is not so hard from one language to other. The hardest part is to understand the spoken language, because the pronunciation is not so similar between these two languages.

I'm native Spanish speaker and at my work there is a guy who speaks Portugues. He doesn't speak Spanish, however, he speaks his own language and so do I and we can understand each other without problem.

@Roberto

Thanks for the explanation

Thank you