This is live pricing from Travelpayouts' aggregation of 40+ booking engines. The $251 fare is the cheapest current round-trip from Miami (MIA) to BOS on Frontier flight F94405, departing 2026-08-13 at 18:42 with return on 2026-08-16.

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