American Airlines has round-trip flights from Dallas (DFW) to Sao Paulo (GRU) for $584, NONSTOP. Flights April to May. No Weekends. Departures on Monday, Tuesday, Wednesday, and Thursday.
A Carry-on bag and also a personal item is allowed for free on American. You can avoid paying for seat selection by accepting the randomly assigned seat at the gate.
Read More Nonstop Flights: Dallas to Sao Paulo $584 r/t [April-May] – American Airlines