AirHint found the following cheapest return flights from San Jose (SJC) to Bangkok (BKK) in September 2025 (see full year).

Return flights

04 Sep - 30 Sep	Korean Air
09 Sep - 28 Sep	Korean Air
09 Sep - 22 Sep	Korean Air
02 Sep - 16 Sep	Korean Air
01 Sep - 16 Sep	Korean Air
03 Sep - 17 Sep	Korean Air
01 Sep - 12 Oct	Korean Air
07 Sep - 22 Sep	Korean Air
16 Sep - 26 Sep	Korean Air
12 Sep - 18 Sep	Korean Air
06 Sep - 14 Sep	Korean Air
29 Sep - 08 Oct	China Airlines
17 Sep - 01 Oct	China Airlines
27 Sep - 11 Oct	EVA Air
25 Sep - 26 Oct	Japan Airlines

Also check the deals for one-way flights from San Jose to Bangkok in September.

The deals are updated regularly. The prices may go up as tickets are purchased by other travellers. Only the cheapest flights are offered. Select a price to book and secure these cheap prices.

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Cheapest return flights from San Jose to Bangkok in September from $715

Return flights