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

Return flights

29 Dec - 13 Jan	Saudia
26 Dec - 16 Jan	Etihad Airways
16 Dec - 27 Dec	ANA
26 Dec - 30 Dec	Etihad Airways
26 Dec - 31 Dec	Etihad Airways
27 Dec - 15 Jan	Etihad Airways
24 Dec - 27 Dec	Qatar Airways
30 Dec - 10 Jan	Saudia
24 Dec - 16 Jan	Etihad Airways
24 Dec - 15 Jan	Etihad Airways
27 Dec - 11 Jan	Porter Airlines (Canada) Ltd
25 Dec - 12 Jan	Qatar Airways
15 Dec - 10 Jan	United
17 Dec - 25 Dec	WestJet
23 Dec - 26 Dec	Qatar Airways
29 Dec - 05 Jan	Saudia
20 Dec - 23 Dec	Icelandair
18 Dec - 25 Dec	Air Canada
20 Dec - 27 Dec	Icelandair
21 Dec - 29 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.

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Cheapest return flights from Washington to Bangkok in December from $1291

Return flights