AirHint found the following cheapest return flights from Washington (IAD) to Bangkok (BKK) in December 2025 (see full year).

Return flights

01 Dec - 15 Dec	Etihad Airways
01 Dec - 21 Dec	Etihad Airways
01 Dec - 19 Dec	Qatar Airways
06 Dec - 20 Dec	Turkish Airlines
01 Dec - 08 Dec	Qatar Airways
04 Dec - 14 Jan	Delta
06 Dec - 20 Jan	IndiGo
04 Dec - 15 Jan	Delta
05 Dec - 15 Jan	Frontier Airlines
09 Dec - 22 Dec	Qatar Airways
09 Dec - 21 Dec	Qatar Airways
06 Dec - 16 Jan	Frontier Airlines
29 Dec - 04 Jan	Turkish Airlines
08 Dec - 07 Jan	Alaska Airlines
08 Dec - 09 Jan	Alaska Airlines
31 Dec - 06 Jan	Qatar Airways
12 Dec - 21 Dec	TAP
23 Dec - 26 Jan	IndiGo
16 Dec - 19 Dec	IndiGo
20 Dec - 31 Dec	Frontier Airlines

Also check the deals for one-way flights from Washington to Bangkok in December.

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.

Book a cheap hotel in Bangkok

Cheap car rent in Bangkok

Cheapest return flights from Washington to Bangkok in December from 732€

Return flights