This is live pricing from Travelpayouts' aggregation of 40+ booking engines. The $610 fare is the cheapest current round-trip from San Francisco (SFO) to GUA on Frontier flight F94000, departing 2026-07-23 at 00:29 with return on 2026-08-06.

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