Several years back, I would have said Varig was the best air carrier for Brazil. However, Varig no longer operates as a named carrier. Varig was merged into GOL.
The three main existing air carriers offer pretty much the same fares, depending on when you travel and when you buy the ticket.
There is GOL, TAM and Azul.
If you book flights on-line and early enough, it is possible to get some very reasonable fares.
There is also a bargain that is not often advertised. It is called -TAM and/or GOL Air Pass.
Here is a link that explains the rules for the air passes. Depending on your travel desires, it is possible to save a fair amount of money using these air passes.
http://www.brol.com/airpass/
As you can see from the link, a minimum of four flights within Brazil must be booked with the Brazil air pass.
When I first started traveling to Brazil, I used to buy these passes fairly often. It was a way to see lots of cities within Brazil. The old rules were less restrictive before the present rules were initiated.
The new rules with GOL, allow a passenger to see not just Brazil but other parts of South America in addition to Brazil. See the link to learn the appropriate rules for each pass.
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