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Cardiff

$362+ Cheap flights from Seattle (SEA) to Cardiff (CWL)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 9/16. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — CWL
Aug 23 — Aug 301
Sat 8/23
Sat 8/30
1 adult, Economy
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Cheap flight deals from Seattle to Cardiff

Discover tips and strategies to find the most affordable flight options for your journey from Seattle (SEA) to Cardiff (CWL). 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 August 18, 2025.

Round-trip from

$831
(Kiwi.com)

One-way from

$362
(Kiwi.com)

Popular in

June

Cheapest in

January

Average price

$929
From Seattle/Tacoma Intl to Cardiff Wales
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One-way flight from Seattle/Tacoma Intl to Cardiff Wales
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Highest demand for flights based on searches. 18% potential increase in price ($266 potential increase over avg. RT price).
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Cheapest flight prices on average. 5% potential price decrease ($60 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 Seattle to Cardiff

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

This Kiwi.com deal was found by Cheapflights users on 8/15. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/307:35 pmSEA - CWL
1 stop27h 50mMultiple Airlines
Tue 10/74:20 pmCWL - SEA
2 stops36h 09mMultiple Airlines
Deal found 8/15$831
This KLM deal was found by Cheapflights users on 8/15. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/305:40 pmSEA - CWL
1 stop15h 05mKLM
Tue 10/79:50 amCWL - SEA
1 stop34h 00mKLM
Deal found 8/15$937
This Delta deal was found by Cheapflights users on 8/15. 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.
Tue 9/3010:15 amSEA - CWL
2 stops22h 30mDelta
Tue 10/79:50 amCWL - SEA
2 stops20h 32mDelta
Deal found 8/15$952
This Virgin Atlantic 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 Virgin Atlantic is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/316:00 amSEA - CWL
2 stops20h 50mVirgin Atlantic
Sun 11/95:30 pmCWL - SEA
2 stops31h 29mVirgin Atlantic
Deal found 8/18$1,090
This KLM 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/132:10 pmSEA - CWL
1 stop35h 05mKLM
Fri 9/199:50 amCWL - SEA
1 stop14h 15mKLM
Deal found 8/16$1,202
This KLM 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/137:45 amSEA - CWL
2 stops17h 30mMultiple Airlines
Fri 9/199:50 amCWL - SEA
2 stops18h 26mMultiple Airlines
Deal found 8/17$1,217
This KLM deal was found by Cheapflights users on 8/15. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/161:40 pmSEA - CWL
2 stops19h 10mKLM
Sat 8/239:50 amCWL - SEA
1 stop14h 05mKLM
Deal found 8/15$1,266

Cheapflights Fare Finder

 
Customize your flight search to find flights from Seattle to Cardiff 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 August 18, 2025.
Use the filters below to find and compare flights from Seattle to Cardiff that are best for you.

Fly from

Seattle

Fly to

Cardiff

Route

Depart

Return

Price

SeattleCardiff

SEA - CWL

SEACWL

Seattle/Tacoma Intl

Tue 9/30

7:35 pm-7:25 am

1 stop27h 50m

Cardiff Wales

Tue 10/7

4:20 pm-8:29 pm

2 stops36h 09m

$831

SeattleCardiff

SEA - CWL

SEACWL

Seattle/Tacoma Intl

Tue 9/30

5:40 pm-4:45 pm

1 stop15h 05m

Cardiff Wales

Tue 10/7

9:50 am-11:50 am

1 stop34h 00m

$937

SeattleCardiff

SEA - CWL

SEACWL

Seattle/Tacoma Intl

Tue 9/30

10:15 am-4:45 pm

2 stops22h 30m

Cardiff Wales

Tue 10/7

9:50 am-10:22 pm

2 stops20h 32m

$952

SeattleCardiff

SEA - CWL

SEACWL

Seattle/Tacoma Intl

Fri 10/31

6:00 am-9:50 am

2 stops20h 50m

Cardiff Wales

Sun 11/9

5:30 pm-4:59 pm

2 stops31h 29m

$1,090

SeattleCardiff

SEA - CWL

SEACWL

Seattle/Tacoma Intl

Sat 9/13

2:10 pm-9:15 am

1 stop35h 05m

Cardiff Wales

Fri 9/19

9:50 am-4:05 pm

1 stop14h 15m

$1,202

SeattleCardiff

SEA - CWL

SEACWL

Seattle/Tacoma Intl

Sat 9/13

7:45 am-9:15 am

2 stops17h 30m

Cardiff Wales

Fri 9/19

9:50 am-8:16 pm

2 stops18h 26m

$1,217

SeattleCardiff

SEA - CWL

SEACWL

Seattle/Tacoma Intl

Tue 9/16

10:41 pm-7:25 am

2 stops24h 44m

$362

Flights are sorted by cheapest round-trip flights first.

Deals found on 8/17

Best time to book a flight from Seattle to Cardiff

Have a flexible travel schedule? Discover the best time to fly to Cardiff from Seattle 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 Seattle to Cardiff

What is the cheapest time of day to fly from SEA to CWL?

Find hourly flight availability from Seattle to Cardiff. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated August 18, 2025.

When flying from Seattle to Cardiff, the time of day you fly usually plays a role in the price. Save by searching for a flight in the morning, which can drop the price by up to 17% versus a flight at noon.

Related info for your journey

Find useful and relevant information for your journey from Seattle to Cardiff. 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 Seattle to Cardiff?

    Departing from Seattle to Cardiff will take you 15h 05m. There are 4709 mi between Seattle and Cardiff. When browsing for deals, the options you’ll see will be for both nonstop flights and flights with stops.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Seattle to Cardiff 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 Seattle to Cardiff?

    Currently, February is the cheapest month in which you can book a flight from Seattle to Cardiff (average of $773). Flying from Seattle to Cardiff in June is currently the most expensive (average of $1,622). 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 Cardiff?

Book flights to Cardiff if you plan to visit one of these locations
Barry

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