This is live pricing from Travelpayouts' aggregation of 40+ booking engines. The $633 fare is the cheapest current round-trip from Boston (BOS) to ROM on DE flight DE2039, departing 2026-06-09 at 16:45 with return on 2026-06-10.
Clicking "Book this flight" opens Kiwi.com with this exact flight pre-filtered — same airline, same dates, same passenger count.