You can say você in Brasil everywhere. Even those - few in comparison - who use tu won't feel like you are obliged to use it too.
I am resurrecting this old thread. I've read through dozens of the posts on this issue. Vanda, I find your comment here, short and sweet, the clearest one of all. Yet I still have questions.
A little background on my personal experience. I was in Brazil for a couple weeks way back in the 1980's. I already knew a small amount of Portuguese, learned from listening to a lot of bossa nova and some self studies from books. From these, I knew that "você" was the normal form of "you" in Brazil. During the trip, it was all I heard except in three cases. Those three were: I overheard a mother speaking to her very young child (maybe 4 or 5 years old) as "tu". I myself was addressed by a child of 9 or 10 as "a senhora". The third case was very interesting. I was in a tour group in which all but myself were Brazilians and Argentines. Of course they could communicate with each other quite well using a combination of Portuguese and Spanish. But when the young Brazilian girl (early 20's) addressed the Argentine gentleman who could have been her grandfather as "el senor" (she was using Spanish at the moment) he said, "El senor?" He couldn't understand why she was talking about the Lord! And she couldn't understand his confusion.
Fast forward to 2010. I was in the Amazon two weeks. I did not hear either tu or el senhor one single time.
Now I am preparing for my third trip to Brazil, and really want to understand this issue. Based on my own experiences described above, I would have no question at all. I would use você at all times, and I would expect everyone to use você with me, except maybe the rare young child whose parents had trained him to address adults as "o senhor". BUT - I am studying Portuguese from various library books, and I am using Pimsleur CD's, and these sources indicate that o senhor is alive and well in Brazil. (I am using exclusively books and CDs teaching Brazilian Portuguese.) The cases that these books and CD's use o senhor, are in business - coworkers speaking to each other, in the service industries - restaurants, hotels, airports, stores, and the like, and with sort of infrastructure positions - police, doctors. My initial reaction was, "this is all wrong". But I've seen it in so many books, and heard it on the Pimsleur CD's, that now I'm starting to wonder.
So, do Brazilians use o senhor in situations like the above? Or is my own instinct correct - that they do not, and do use você in all such situations. Secondly, if they do use o senhor, I know they would be lenient with a foreigner who used você instead. But would they feel a tiny bit uneasy about it? Also, I did see your post somewhere in this thread (or one of the other threads on this issue) that Brazilians over about age 60 do use o senhor. Understood. So I am asking about the younger ones.
Sorry to write all in English. I want to improve my speaking, but not so much my writing. Especially on somewhat complicated topics, it would be extremely poor. However, I can read Portuguese entries in these forums with at least 90% comprehension, so please feel free to answer in Portuguese.
Thank you so much.