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Cardiff

$430+ 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 6/17. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — CWL
Jan 27 — Feb 31
Tue 1/27
Tue 2/3
1 adult, Economy
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Cheap flight deals from Seattle to Cardiff

Best flights from Seattle to Cardiff
Discover carefully curated flight deals from Seattle to Cardiff that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated December 28, 2025.

This KLM deal was found by Cheapflights users on 12/27. 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 2/103:05 pmSEA - CWL
1 stop34h 45mKLM
Tue 2/175:25 pmCWL - SEA
1 stop26h 15mKLM
Deal found 12/27$815
This Delta deal was found by Cheapflights users on 12/27. 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 2/106:05 amSEA - CWL
2 stops19h 45mDelta
Tue 2/1710:20 amCWL - SEA
2 stops20h 02mDelta
Deal found 12/27$1,039
This WestJet deal was found by Cheapflights users on 12/26. 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 WestJet is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/237:05 amSEA - CWL
2 stops43h 10mWestJet
Tue 6/3011:35 amCWL - SEA
2 stops39h 03mWestJet
Deal found 12/26$1,267
This KLM deal was found by Cheapflights users on 12/25. 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.
Mon 2/93:05 pmSEA - CWL
1 stop17h 50mMultiple Airlines
Mon 2/165:45 pmCWL - SEA
1 stop25h 40mMultiple Airlines
Deal found 12/25$1,286
This KLM deal was found by Cheapflights users on 12/26. 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 6/235:35 pmSEA - CWL
1 stop31h 40mKLM
Tue 6/305:15 pmCWL - SEA
1 stop31h 05mKLM
Deal found 12/26$1,335
This KLM deal was found by Cheapflights users on 12/26. 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 6/235:35 pmSEA - CWL
1 stop31h 40mMultiple Airlines
Tue 6/309:45 amCWL - SEA
2 stops20h 20mMultiple Airlines
Deal found 12/26$1,345

Find 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 December 28, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

Ovago
2 stars

Round-trip from

$815
(KLM)

One-way from

$430
(WestJet)
Provider with most accurate pricing for Seattle/Tacoma Intl-Cardiff Wales flight deals.
Search Deals
Provider most trusted by Cheapflights users for Seattle/Tacoma Intl-Cardiff Wales flights.
Search Deals
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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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 December 28, 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 2/10

3:05 pm-9:50 am

1 stop34h 45m

Cardiff Wales

Tue 2/17

5:25 pm-11:40 am

1 stop26h 15m

$815

SeattleCardiff

SEA - CWL

SEACWL

Seattle/Tacoma Intl

Tue 2/10

6:05 am-9:50 am

2 stops19h 45m

Cardiff Wales

Tue 2/17

10:20 am-10:22 pm

2 stops20h 02m

$1,039

SeattleCardiff

SEA - CWL

SEACWL

Seattle/Tacoma Intl

Tue 6/23

7:05 am-10:15 am

2 stops43h 10m

Cardiff Wales

Tue 6/30

11:35 am-6:38 pm

2 stops39h 03m

$1,267

SeattleCardiff

SEA - CWL

SEACWL

Seattle/Tacoma Intl

Mon 2/9

3:05 pm-4:55 pm

1 stop17h 50m

Cardiff Wales

Mon 2/16

5:45 pm-11:25 am

1 stop25h 40m

$1,286

SeattleCardiff

SEA - CWL

SEACWL

Seattle/Tacoma Intl

Tue 6/23

5:35 pm-9:15 am

1 stop31h 40m

Cardiff Wales

Tue 6/30

5:15 pm-4:20 pm

1 stop31h 05m

$1,335

SeattleCardiff

SEA - CWL

SEACWL

Seattle/Tacoma Intl

Tue 6/23

5:35 pm-9:15 am

1 stop31h 40m

Cardiff Wales

Tue 6/30

9:45 am-10:05 pm

2 stops20h 20m

$1,345

SeattleCardiff

SEA - CWL

SEACWL

Seattle/Tacoma Intl

Thu 6/18

7:05 am-10:15 am

2 stops43h 10m

$430

SeattleCardiff

SEA - CWL

SEACWL

Seattle/Tacoma Intl

Wed 6/17

7:05 am-10:15 am

2 stops19h 10m

$430

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/26

Compare providers for flights from Seattle to Cardiff

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Seattle to Cardiff in December.
ProviderPrice AccuracyTrust Score*
FlightHubPrice Accuracy3 starsTrust Score*1 star
OvagoPrice Accuracy2 starsTrust Score*2 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Seattle-Cardiff flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Seattle-Cardiff flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Seattle-Cardiff flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Seattle-Cardiff flights, Cheapflights users trust Ovago the most. Ovago has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Seattle-Cardiff flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

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.

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 19h 45m. 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.

See more FAQs

Traveling to a place near Cardiff?

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

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