This is live pricing from Travelpayouts' aggregation of 40+ booking engines. The $671 fare is the cheapest current round-trip from Boston (BOS) to BCN on Air Canada flight AC753, departing 2026-05-12 at 15:40 with return on 2026-05-20.

Clicking "Book this flight" opens Kiwi.com with this exact flight pre-filtered — same airline, same dates, same passenger count.