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$560+ Cheap flights from Basel EuroAirport Swiss (BSL) to Seattle (SEA)

This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 9/29. Fares are subject to change and may not be available on all flights or dates of travel.
BSL — SEA
ago. 23 — ago. 301
sáb. 8/23
sáb. 8/30
1 adult, Economy
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Cheap flight deals from Basel to Seattle

Discover tips and strategies to find the most affordable flight options for your journey from Basel (BSL) to Seattle (SEA). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated agosto 18, 2025.

Round-trip from

$560
(Billigflug)

Popular in

July

Cheapest in

November

Average price

$736
From Basel EuroAirport Swiss to Seattle/Tacoma Intl
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Highest demand for flights based on searches. 20% potential increase in price ($170 potential increase over avg. RT price).
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Cheapest flight prices on average. 6% potential price decrease ($41 potential savings vs. average RT price).
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Average for round-trip flights in August 2025
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Find flight deals from Basel to Seattle

Cheapest flights from Basel to Seattle
Explore the most affordable flight options available from Basel to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on agosto 18, 2025.

This Billigflug deal was found by Cheapflights users on 8/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Billigflug is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 10/16:40 amBSL - SEA
1 stop13h 55mBritish Airways
jue. 10/161:30 pmSEA - BSL
1 stop12h 25mBritish Airways
Deal found 8/17$560
This American Airlines deal was found by Cheapflights users on 8/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 9/86:35 amBSL - SEA
1 stop14h 00mAmerican Airlines
mar. 10/71:30 pmSEA - BSL
1 stop24h 20mAmerican Airlines
Deal found 8/17$561
This Expedia deal was found by Cheapflights users on 8/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 12/207:10 amBSL - SEA
1 stop13h 20mBritish Airways
dom. 12/286:50 pmSEA - BSL
1 stop30h 25mBritish Airways
Deal found 8/16$562
This American Airlines deal was found by Cheapflights users on 8/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jue. 9/116:10 amBSL - SEA
1 stop14h 25mAmerican Airlines
lun. 10/65:22 amSEA - BSL
2 stops20h 38mAmerican Airlines
Deal found 8/17$565
This American Airlines deal was found by Cheapflights users on 8/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 8/306:35 amBSL - SEA
2 stops26h 06mAmerican Airlines
vie. 11/2811:45 amSEA - BSL
2 stops20h 20mAmerican Airlines
Deal found 8/16$566
This American Airlines deal was found by Cheapflights users on 8/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 9/66:35 amBSL - SEA
2 stops20h 53mAmerican Airlines
mar. 10/712:30 pmSEA - BSL
2 stops25h 20mAmerican Airlines
Deal found 8/17$567
This Delta deal was found by Cheapflights users on 8/16. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 8/306:15 amBSL - SEA
1 stop14h 20mDelta
sáb. 11/291:40 pmSEA - BSL
1 stop15h 10mDelta
Deal found 8/16$570
This Delta deal was found by Cheapflights users on 8/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 9/1010:10 amBSL - SEA
1 stop14h 55mDelta
lun. 10/65:40 pmSEA - BSL
1 stop15h 10mDelta
Deal found 8/17$575
This Delta deal was found by Cheapflights users on 8/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
vie. 10/36:15 amBSL - SEA
2 stops17h 38mDelta
lun. 10/139:46 amSEA - BSL
2 stops18h 24mDelta
Deal found 8/17$576
This American Airlines deal was found by Cheapflights users on 8/18. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 10/66:35 amBSL - SEA
2 stops20h 35mAmerican Airlines
lun. 10/137:44 amSEA - BSL
2 stops19h 01mAmerican Airlines
Deal found 8/18$579
This Delta deal was found by Cheapflights users on 8/17. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 9/136:15 amBSL - SEA
1 stop14h 30mDelta
mar. 10/77:19 amSEA - BSL
2 stops20h 51mDelta
Deal found 8/17$596

Cheapflights Fare Finder

 
Customize your flight search to find flights from Basel to Seattle that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated agosto 18, 2025.
Use the filters below to find and compare flights from Basel EuroAirport Swiss to Seattle that are best for you.

Fly from

Basel

Fly to

Seattle

Route

Depart

Return

Price

BaselSeattle

BSL - SEA

BSLSEA

Basel EuroAirport Swiss

lun. 9/29

6:35 am-11:35 am

1 stop14h 00m

Seattle/Tacoma Intl

dom. 10/5

3:00 pm-10:50 pm

2 stops22h 50m

$560

BaselSeattle

BSL - SEA

BSLSEA

Basel EuroAirport Swiss

mié. 10/1

11:50 am-11:35 am

1 stop32h 45m

Seattle/Tacoma Intl

jue. 10/16

2:52 pm-10:50 pm

2 stops22h 58m

$560

BaselSeattle

BSL - SEA

BSLSEA

Basel EuroAirport Swiss

mié. 10/1

6:40 am-11:35 am

1 stop13h 55m

Seattle/Tacoma Intl

jue. 10/16

1:30 pm-10:55 am

1 stop12h 25m

$560

BaselSeattle

BSL - SEA

BSLSEA

Basel EuroAirport Swiss

lun. 10/6

12:10 pm-11:10 am

1 stop32h 00m

Seattle/Tacoma Intl

dom. 10/12

2:52 pm-10:50 pm

2 stops22h 58m

$560

BaselSeattle

BSL - SEA

BSLSEA

Basel EuroAirport Swiss

vie. 12/5

11:15 am-4:55 pm

1 stop14h 40m

Seattle/Tacoma Intl

vie. 12/19

1:35 pm-5:05 pm

1 stop18h 30m

$561

BaselSeattle

BSL - SEA

BSLSEA

Basel EuroAirport Swiss

vie. 9/12

6:00 am-11:35 am

1 stop14h 35m

Seattle/Tacoma Intl

sáb. 10/4

8:20 pm-11:20 am

1 stop30h 00m

$561

BaselSeattle

BSL - SEA

BSLSEA

Basel EuroAirport Swiss

mar. 9/9

6:45 am-11:10 am

1 stop13h 25m

Seattle/Tacoma Intl

jue. 10/2

8:20 pm-6:25 pm

1 stop13h 05m

$561

BaselSeattle

BSL - SEA

BSLSEA

Basel EuroAirport Swiss

mié. 9/10

11:50 am-11:35 am

1 stop32h 45m

Seattle/Tacoma Intl

lun. 10/6

1:30 pm-10:50 pm

1 stop24h 20m

$561

BaselSeattle

BSL - SEA

BSLSEA

Basel EuroAirport Swiss

vie. 9/12

6:00 am-11:35 am

1 stop14h 35m

Seattle/Tacoma Intl

lun. 10/6

8:20 pm-10:50 pm

1 stop17h 30m

$561

BaselSeattle

BSL - SEA

BSLSEA

Basel EuroAirport Swiss

dom. 9/7

7:05 am-11:30 am

1 stop13h 25m

Seattle/Tacoma Intl

sáb. 10/4

8:20 pm-10:50 pm

1 stop17h 30m

$561

Flights are sorted by cheapest round-trip flights first.

Deals found on 8/17

Showing 1-10 of 21 results
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Best time to book a flight from Basel to Seattle

Have a flexible travel schedule? Discover the best time to fly to Seattle from Basel with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from Basel EuroAirport Swiss to Seattle

How much does it cost to fly round-trip from Basel EuroAirport Swiss to Seattle?

Related info for your journey

Find useful and relevant information for your journey from Basel to Seattle. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • How long is the flight from Basel EuroAirport Swiss to Seattle?

    Departing from Basel EuroAirport Swiss to Seattle will take you 13h 55m. Airlines will cover a distance of 5207 mi. This flight may include one or multiple stops.

  • Can I find deals for flights from Basel to Seattle that include hotel bookings?

    Yes. In addition to deals on Basel to Seattle flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Basel to Seattle?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Basel to Seattle.

  • Can I find deals for business class flights from Basel to Seattle?

    Yes. Cheapflights offers flight deals from Basel to Seattle by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Basel EuroAirport Swiss to Seattle?

    Currently, January is the cheapest month in which you can book a flight from Basel EuroAirport Swiss to Seattle (average of $238). Flying from Basel EuroAirport Swiss to Seattle in June is currently the most expensive (average of $388). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Traveling to a place near Seattle?

Book flights to Seattle if you plan to visit one of these locations
SeaTac
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Tacoma
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Leavenworth
Renton
Olympia
Puyallup
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Shelton

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