Flights Bangkok → Seattle (BKK-SEA) — THB Fares, Airlines, Frequency

Bangkok to Seattle links Thailand with the US Pacific Northwest, a region with a steady Thai community and a strong pull for students and technology-sector professionals. The route carries people visiting family, students, professionals and travellers using Seattle as their entry point to the Northwest and onward across the United States.

There is no nonstop service; block times near 17.5 hours reflect a connection through the operating carrier’s Asian hub. At around 7 flights a week — roughly daily — the corridor is dependable, with demand rising around the year-end holidays and the long mid-year break.

Airlines on this route

Three carriers serve BKK-SEA, all full-service and all routing via a hub: EVA Air via Taipei, Cathay Pacific via Hong Kong and Korean Air via Seoul’s Incheon. On a journey approaching eighteen hours, the connecting airport, the layover and the checked baggage allowance matter as much as the fare. With three options, comparing schedules and layover lengths on your travel dates is usually worth the effort.

THB fares

BKK-SEA is a long-haul route where booking ahead pays off. The year-end holidays and the mid-year break are the busiest and dearest — eight to fourteen weeks of lead time is sensible for those windows. Outside them, a six-to-ten-week window often finds a workable economy fare in THB, with the hub carriers competing on connecting itineraries. Flexibility on dates and on the transit hub both help keep the cost down.

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About Seattle

Seattle is the largest city of the US Pacific Northwest, set between Puget Sound and the mountains, with a green, rainy climate and a strong technology economy that draws professionals and students worldwide. It has a settled Thai community, with temples and restaurants across the metro area. For Thai travellers, Seattle serves as a family destination, a study or work base, and a gateway to the Northwest’s national parks and onward US travel.

FAQ

Which airlines fly Bangkok to Seattle? Direct BKK-SEA flights are operated by EVA Air, Cathay Pacific, Korean Air. Compare baggage allowance, fares and schedules in the carrier table above.

How long is the BKK-SEA flight and how often does it run? Block time is about 17.5 hours. The BKK-SEA route runs roughly 7 flights per week across all carriers.

How far ahead should I book BKK-SEA for the best fare? Booking 4-8 weeks ahead for regular dates, and 10-14 weeks for peak periods (Songkran, New Year, Hajj/Umrah season), typically saves 15-30%. See the month-by-month fare heatmap above.

What is the checked baggage allowance on BKK-SEA? It varies by carrier and fare class — full-service carriers on this route usually include 20-30 kg, while low-cost carriers sell it as an add-on. Confirm the current policy on the airline’s site before booking. Migrant workers should check each carrier’s extra-baggage uplift.

What currency is used in Seattle? Seattle uses USD. Compare airfares in THB and budget on-the-ground spending in USD.

Related routes

• BKK airport
• SEA airport