What are the cheapest airlines flying from Seattle to Cardiff round-trip?

Cheapflights users have booked flights from Seattle to Cardiff round-trip from $913. Other airlines that can offer you cheap pricing are Air France, from $1,632, and Delta, from $1,656. These flights start at 21% lower than the current average price 3 months from now.

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.

What is the cheapest day to fly from Seattle to Cardiff?

Travelers seeking maximum savings on their Seattle to Cardiff flight should consider departing on Sunday afternoons when fares are most often at their lowest. Monday afternoons flights should be avoided if possible as fares are typically the most expensive at this time.

What is the cheapest day to fly round-trip from Seattle to Cardiff?

Users have found that flying from Seattle to Cardiff on a Sunday typically leans towards higher prices. However, this doesn’t mean you still can’t find a deal. Flexibility with other aspects of your flight can still land a great price for your trip.

What is the cheapest month to fly from Seattle to Cardiff?

January can be a great time to fly to Cardiff from Seattle with a flight ticket averaging about $1,161. Cheapflights users have found deals in the month of January for as cheap as $878. The most expensive prices can be found in the month of July.

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 FlightHub the most. FlightHub 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.

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.

$850+ Flights from Seattle to Cardiff

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1. Tell us where you want to go

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Cheap flight deals from Seattle to Cardiff

Most accurate provider	FlightHub 3 stars
Most trusted provider	FlightHub 2 stars
Round-trip from	$913 (KLM)
One-way from	$850 (KLM)
Popular in	July
Cheapest in	January
Average price	$1,071

Provider with most accurate pricing for Seattle/Tacoma Intl-Cardiff Wales flight deals.

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Provider most trusted by Cheapflights users for Seattle/Tacoma Intl-Cardiff Wales flights.

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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. 21% potential increase in price ($313 potential increase over avg. RT price).

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Cheapest flight prices on average. 4% potential price decrease ($50 potential savings vs. average RT price).

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Average for round-trip flights in May 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 May 15, 2025.

Mon 10/62:10 pmSEA - CWL

1 stop35h 05mKLM

Thu 10/165:15 pmCWL - SEA

1 stop30h 50mKLM

Deal found 5/13

$913

Mon 10/63:30 pmSEA - CWL

2 stops17h 15mMultiple Airlines

Thu 10/169:50 amCWL - SEA

2 stops20h 23mMultiple Airlines

Deal found 5/13

$927

Wed 5/146:07 pmSEA - CWL

1 stop14h 38mDelta

Wed 5/219:50 amCWL - SEA

1 stop14h 07mDelta

Deal found 5/13

$1,546

Sat 6/285:35 pmSEA - CWL

1 stop15h 15mAir France

Sat 7/59:45 amCWL - SEA

1 stop14h 05mAir France

Deal found 5/14

$1,632

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 May 15, 2025.

Mon 10/62:10 pmSEA - CWL

1 stop35h 05mKLM

Thu 10/165:15 pmCWL - SEA

1 stop30h 50mKLM

Deal found 5/13

$913

Mon 10/63:30 pmSEA - CWL

2 stops17h 15mMultiple Airlines

Thu 10/169:50 amCWL - SEA

2 stops20h 23mMultiple Airlines

Deal found 5/13

$927

Sat 6/285:35 pmSEA - CWL

1 stop15h 15mAir France

Sat 7/59:45 amCWL - SEA

1 stop14h 05mAir France

Deal found 5/14

$1,632

Sat 6/289:43 amSEA - CWL

2 stops23h 07mDelta

Sat 7/59:45 amCWL - SEA

2 stops21h 04mDelta

Deal found 5/14

$1,656

Last-minute flights from Seattle to Cardiff
Discover last-minute flight deals from Seattle to Cardiff. Data last updated May 15, 2025 and is based on user searches.

Mon 6/97:05 amSEA - CWL

2 stops24h 50mMultiple Airlines

Mon 6/161:10 pmCWL - SEA

3 stops41h 03mMultiple Airlines

Deal found 5/14

$988

Mon 6/95:35 pmSEA - CWL

1 stop31h 40mKLM

Mon 6/165:15 pmCWL - SEA

1 stop30h 40mKLM

Deal found 5/14

$1,266

Sat 6/285:35 pmSEA - CWL

1 stop15h 15mAir France

Sat 7/59:45 amCWL - SEA

1 stop14h 05mAir France

Deal found 5/14

$1,632

Sat 6/289:43 amSEA - CWL

2 stops23h 07mDelta

Sat 7/59:45 amCWL - SEA

2 stops21h 04mDelta

Deal found 5/14

$1,656

One-way flights from Seattle to Cardiff
Search for one-way flight options from Seattle to Cardiff. Find affordable one-way fares based on user searches. Data last updated May 15, 2025.

Sun 6/291:55 pmSEA - CWL

1 stop18h 50mKLM

Deal found 5/15

$850

Sat 6/287:05 amSEA - CWL

3 stops29h 05mMultiple Airlines

Deal found 5/14

$1,876

Cheapflights Fare Finder

Use the filters below to find and compare flights from Seattle to Cardiff that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

SeattleCardiff

SEA - CWL

SEACWL

Seattle/Tacoma Intl

Mon 10/6

2:10 pm-9:15 am

1 stop35h 05m

Cardiff Wales

Thu 10/16

5:15 pm-4:05 pm

1 stop30h 50m

$913

SeattleCardiff

SEA - CWL

SEACWL

Seattle/Tacoma Intl

Mon 10/6

3:30 pm-4:45 pm

2 stops17h 15m

Cardiff Wales

Thu 10/16

9:50 am-10:13 pm

2 stops20h 23m

$927

SeattleCardiff

SEA - CWL

SEACWL

Seattle/Tacoma Intl

Sat 6/28

5:35 pm-4:50 pm

1 stop15h 15m

Cardiff Wales

Sat 7/5

9:45 am-3:50 pm

1 stop14h 05m

$1,632

SeattleCardiff

SEA - CWL

SEACWL

Seattle/Tacoma Intl

Sat 6/28

9:43 am-4:50 pm

2 stops23h 07m

Cardiff Wales

Sat 7/5

9:45 am-10:49 pm

2 stops21h 04m

$1,656

SeattleCardiff

SEA - CWL

SEACWL

Seattle/Tacoma Intl

Sun 6/29

1:55 pm-4:45 pm

1 stop18h 50m

$850

SeattleCardiff

SEA - CWL

SEACWL

Seattle/Tacoma Intl

Sat 6/28

7:05 am-8:10 pm

3 stops29h 05m

$1,876

Flights are sorted by cheapest round-trip flights first.

Deals found on 5/15

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 FlightHub the most. FlightHub 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.

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?

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.

Rainfall in Cardiff by month

In terms of precipitation, rainfall in Cardiff ranges from 2.0 - 3.5 inches per month. January is typically the wettest month, when rainfall can reach 3.5 in. April is typically the driest time to visit Cardiff when rainfall is around 2.0 in.

Temperature in Cardiff by month

If weather is an important factor for your trip to Cardiff, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 64.4 F. Travelers looking to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 39.2 F).

Reviews of airlines servicing Cardiff

Delta

8.0

Very good

7,946 reviews

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

Delta

8.0

Very good

7,946 reviews

Delta

8.0

Very good

7,946 reviews

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

KLM

7.8

Good

1,344 reviews

Delta

8.0

Very good

7,946 reviews

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

Air France

7.4

Good

1,451 reviews

Delta

8.0

Very good

7,946 reviews

Reviews

1 / 20

10.0

Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

Related info for your journey

What are the cheapest airlines flying from Seattle to Cardiff round-trip?
Cheapflights users have booked flights from Seattle to Cardiff round-trip from $913. Other airlines that can offer you cheap pricing are Air France, from $1,632, and Delta, from $1,656. These flights start at 21% lower than the current average price 3 months from now.
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

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Alternative routes for Seattle to Cardiff

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Top 2 airlines flying from Seattle to Cardiff

Airline	Cheapest	Average	Flexibility	On-time
Delta	Cheapest$742	Average$1,214	FlexibilityNo cancel fee	On-timeN/A
KLM	Cheapest$760	Average$1,233	FlexibilityNo cancel fee	On-time75%

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$850+ 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 6/29. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from Seattle to Cardiff with Cheapflights

1. Tell us where you want to go

2. Select your favorite providers

3. Compare prices and book

Cheap flight deals from Seattle to Cardiff

Most accurate provider

Most trusted provider

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Find flight deals from Seattle to Cardiff

Cheapest flights from Seattle to CardiffExplore 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 May 15, 2025.

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 May 15, 2025.

Cheapflights Fare Finder

Use the filters below to find and compare flights from Seattle to Cardiff that are best for you.

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.

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 May 15, 2025.

Rainfall in Cardiff by month

Plan your trip to Cardiff by taking into account the average rainfall totals by month.

Temperature in Cardiff by month

Plan your trip to Cardiff by taking into account the average temperature totals by month.

Reviews of airlines servicing Cardiff

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.

What are the cheapest airlines flying from Seattle to Cardiff round-trip?

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

How can I find direct flights from Seattle to Cardiff?

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

What is the cheapest month to book a flight from Seattle to Cardiff?

Traveling to a place near Seattle?

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Alternative routes for Seattle to Cardiff

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Top 2 airlines flying from Seattle to Cardiff

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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 May 15, 2025.