How long is the flight from Cardiff to Seattle?

Departing from Cardiff to Seattle will take you 14h 50m. Airlines will cover a distance of 4709 mi. Both multi-stop and direct flights can be found to your destination and back.

In terms of precipitation, rainfall in Seattle ranges from 18.0 - 168.0 inches per month. November is typically the wettest month, when rainfall can reach 168.0 mm. July is typically the driest time to visit Seattle when rainfall is around 18.0 mm.

If weather is an important factor for your trip to Seattle, 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 19.0 C. Travellers hoping to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 5.0 C).

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

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Cardiff to Seattle as you normally would.

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

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

How can I find direct flights from Cardiff to Seattle?

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

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

Yes. Cheapflights offers flight deals from Cardiff 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.

£452+ Cheap Flights from Cardiff to Seattle

Cheap flight deals from Cardiff to Seattle

Enter your travel dates to find the best prices.

Cheapest

Best

Last-minute

One-way

Cheapest flights from Cardiff to Seattle
Explore the most affordable flight options available from Cardiff to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 19 September 2026.

Sun 1/1110:20 -

1 stop33h 27m

Sun 8/1114:35 -

1 stop18h 25m

Deal found 17/9£573

Sun 1/1117:30 -

2 stops34h 46m

Sun 8/1110:37 -

2 stops15h 13m

Deal found 17/9£595

Thu 8/1009:45 -

1 stop14h 50m

Tue 13/1013:45 -

1 stop19h 00m

Deal found 15/9£623

Wed 7/1009:45 -

2 stops22h 14m

Thu 15/1013:45 -

1 stop19h 00m

Deal found 15/9£627

Fri 9/1009:45 -

2 stops21h 04m

Tue 13/1017:45 -

1 stop15h 00m

Deal found 15/9£630

Fri 9/1009:45 -

2 stops21h 04m

Thu 15/1007:15 -

2 stops18h 00m

Deal found 15/9£695

Sun 20/1210:20 -

2 stops38h 29m

Mon 4/114:25 -

1 stop18h 35m

Deal found 17/9£885

Sun 20/1217:30 -

1 stop26h 20m

Mon 4/114:25 -

1 stop18h 35m

Deal found 17/9£938

Find flight deals from Cardiff to Seattle

Round-trip from	£573
One-way from	£452

KLM
1/11-8/11
2 total stops
51h 52m total
Cardiff to Seattle

Search Deals

11/12-31/12
3 total stops
32h 55m total
Cardiff to Seattle

Search Deals

Fly from

Fly to

Route

Depart

Return

Price

Cheapest return flight

CardiffSeattle

CWL Cardiff Wales - SEA Seattle/Tacoma Intl

CWLSEA

Cardiff Wales

Fri 11/12

16:05-17:00

3 stops32h 55m

Seattle/Tacoma Intl

Wed 31/12

00:00-09:00

Nonstop0h 00m

£452

Fastest return journey

CardiffSeattle

CWL Cardiff Wales - SEA Seattle/Tacoma Intl

CWLSEA

Cardiff Wales

Fri 11/12

17:30-11:50

1 stop26h 20m

Seattle/Tacoma Intl

Wed 31/12

00:00-09:00

Nonstop0h 00m

£568

CardiffSeattle

CWL Cardiff Wales - SEA Seattle/Tacoma Intl

CWLSEA

Cardiff Wales

Sun 1/11

10:20-11:47

1 stop33h 27m

Seattle/Tacoma Intl

Sun 8/11

14:35-17:00

1 stop18h 25m

£573

CardiffSeattle

CWL Cardiff Wales - SEA Seattle/Tacoma Intl

CWLSEA

Cardiff Wales

Sun 1/11

17:30-20:16

2 stops34h 46m

Seattle/Tacoma Intl

Sun 8/11

10:37-09:50

2 stops15h 13m

£595

CardiffSeattle

CWL Cardiff Wales - SEA Seattle/Tacoma Intl

CWLSEA

Cardiff Wales

Thu 8/10

09:45-16:35

1 stop14h 50m

Seattle/Tacoma Intl

Thu 15/10

13:45-16:45

1 stop19h 00m

£623

CardiffSeattle

CWL Cardiff Wales - SEA Seattle/Tacoma Intl

CWLSEA

Cardiff Wales

Wed 7/10

09:45-16:35

1 stop14h 50m

Seattle/Tacoma Intl

Thu 15/10

13:45-16:45

1 stop19h 00m

£623

CardiffSeattle

CWL Cardiff Wales - SEA Seattle/Tacoma Intl

CWLSEA

Cardiff Wales

Thu 8/10

09:45-16:35

1 stop14h 50m

Seattle/Tacoma Intl

Wed 14/10

17:45-09:15

1 stop31h 30m

£623

CardiffSeattle

CWL Cardiff Wales - SEA Seattle/Tacoma Intl

CWLSEA

Cardiff Wales

Fri 9/10

09:45-22:49

2 stops21h 04m

Seattle/Tacoma Intl

Tue 13/10

17:45-16:45

1 stop15h 00m

£630

CardiffSeattle

CWL Cardiff Wales - SEA Seattle/Tacoma Intl

CWLSEA

Cardiff Wales

Tue 19/1

10:20-11:50

1 stop33h 30m

Seattle/Tacoma Intl

Thu 28/1

14:25-17:00

1 stop18h 35m

£630

CardiffSeattle

CWL Cardiff Wales - SEA Seattle/Tacoma Intl

CWLSEA

Cardiff Wales

Tue 19/1

10:20-22:05

2 stops19h 45m

Seattle/Tacoma Intl

Wed 27/1

11:25-17:00

2 stops21h 35m

£634

Flights are sorted by cheapest return flights first.

Deals found on 14/9

Sorted by cheapest first

Best time to book a flight from Cardiff to Seattle

Have a flexible travel schedule? Discover the best time to fly to Seattle from Cardiff with our price prediction graph.

CWL-SEA

Estimated return 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

How long is the flight from Cardiff to Seattle?
Departing from Cardiff to Seattle will take you 14h 50m. Airlines will cover a distance of 4709 mi. Both multi-stop and direct flights can be found to your destination and back.
Can I find deals for flights from Cardiff to Seattle that include hotel bookings?
Yes. In addition to deals on Cardiff to Seattle flights, Cheapflights offers holiday packages that include both flights and hotel.
How can I find direct flights from Cardiff to Seattle?
After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Cardiff to Seattle.
Can I find deals for business class flights from Cardiff to Seattle?
Yes. Cheapflights offers flight deals from Cardiff 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.

See more FAQs

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Why should you use Cheapflights to find cheap flight tickets from Cardiff to Seattle?

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Cheap flights from Cardiff to Seattle from £452

This is the cheapest retur flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 11/12. Fares are subject to change and may not be available on all flights or dates of travel.

Cheap flight deals from Cardiff to Seattle

Cheapest flights from Cardiff to SeattleExplore the most affordable flight options available from Cardiff to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 19 September 2026.

Explore the most affordable flight options available from Cardiff to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 19 September 2026.

Best flights from Cardiff to SeattleDiscover carefully curated flight deals from Cardiff to Seattle that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 19 September 2026.

Discover carefully curated flight deals from Cardiff to Seattle that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 19 September 2026.

Last-minute flights from Cardiff to SeattleDiscover last-minute flight deals from Cardiff to Seattle. Data last updated 19 September 2026 and is based on user searches.

Discover last-minute flight deals from Cardiff to Seattle. Data last updated 19 September 2026 and is based on user searches.

One-way flights from Cardiff to SeattleSearch for one-way flight options from Cardiff to Seattle. Find affordable one-way fares based on user searches. Data last updated 19 September 2026.

Search for one-way flight options from Cardiff to Seattle. Find affordable one-way fares based on user searches. Data last updated 19 September 2026.

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Best time to book a flight from Cardiff to Seattle

Have a flexible travel schedule? Discover the best time to fly to Seattle from Cardiff with our price prediction graph.

Related info for your journey

How long is the flight from Cardiff to Seattle?

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

How can I find direct flights from Cardiff to Seattle?

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

Travelling to a place near Seattle?

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for Cardiff to Seattle

See prices for flight routes from nearby airports that may be better suited for you.

Complete your trip

Complete your trip to Seattle by adding a car hire and/or hotel booking to your travel itinerary.

Direct flights to Washington

Book a non-stop flight to one of these other cities located in Washington.

Search flights from Cardiff to Seattle by cabin class

Find flights from Cardiff to Seattle, based on your preferred cabin class, be it economy, premium economy, business, or first class.

Cardiff and Seattle flights

Browse other Cardiff and Seattle flight options. Last updated on 19 September 2026.

Other flights from Cardiff

Browse through other flights departing from Cardiff. Flights are based on user searches made on Cheapflights and were last updated on 19 September 2026.

Popular flight searches

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Other flights to Seattle

Explore flights to Seattle departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on 19 September 2026.

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How does Cheapflights help users find flights from Cardiff to Seattle?

Why should you use Cheapflights to find cheap flight tickets from Cardiff to Seattle?

Can Cheapflights find flights from Cardiff to Seattle with no change fees?

Can Cheapflights notify me if prices for flights from Cardiff to Seattle become cheaper?

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Cheapest flights from Cardiff to Seattle
Explore the most affordable flight options available from Cardiff to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 19 September 2026.

Best flights from Cardiff to Seattle
Discover carefully curated flight deals from Cardiff to Seattle that have cost, travel time, and stopovers in mind to ensure you get the best travel experience. Data last updated 19 September 2026.

Last-minute flights from Cardiff to Seattle
Discover last-minute flight deals from Cardiff to Seattle. Data last updated 19 September 2026 and is based on user searches.

One-way flights from Cardiff to Seattle
Search for one-way flight options from Cardiff to Seattle. Find affordable one-way fares based on user searches. Data last updated 19 September 2026.