How long is the flight from Cardiff to Seattle?

Departing from Cardiff to Seattle will take you 33h. Airlines will cover a distance of 4709 mi.

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.

£400+ Cheap Flights from Cardiff to Seattle

Cheap flight deals from Cardiff to Seattle

Enter your travel dates to find the best prices.

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Best

Last-minute

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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 13 September 2026.

Sun 25/1010:20 -

2 stops39h 45m

Sun 1/1116:00 -

2 stops41h 00m

Deal found 10/9£593

Sun 25/1017:30 -

1 stop26h 17m

Sun 1/1114:35 -

1 stop18h 25m

Deal found 10/9£645

Sat 24/1009:45 -

1 stop14h 50m

Sat 31/1015:25 -

1 stop18h 35m

Deal found 9/9£655

Sat 24/1017:35 -

2 stops33h 00m

Sat 31/1015:25 -

1 stop18h 35m

Deal found 9/9£792

Sun 25/1017:30 -

2 stops30h 15m

Sun 1/1106:00 -

2 stops19h 50m

Deal found 9/9£883

Find flight deals from Cardiff to Seattle

Round-trip from	£593
One-way from	£400

KLM
25/10-1/11
4 total stops
80h 45m total
Cardiff to Seattle

Search Deals

28/9-31/12
2 total stops
43h 30m 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

Mon 28/9

22:10-09:40

2 stops43h 30m

Seattle/Tacoma Intl

Wed 31/12

00:00-09:00

Nonstop0h 00m

£400

Fastest return journey

CardiffSeattle

CWL Cardiff Wales - SEA Seattle/Tacoma Intl

CWLSEA

Cardiff Wales

Sat 24/10

09:45-16:35

1 stop14h 50m

Seattle/Tacoma Intl

Sat 31/10

15:25-17:00

1 stop18h 35m

£655

CardiffSeattle

CWL Cardiff Wales - SEA Seattle/Tacoma Intl

CWLSEA

Cardiff Wales

Sat 24/10

17:35-18:35

2 stops33h 00m

Seattle/Tacoma Intl

Sat 31/10

06:00-09:50

2 stops20h 50m

£792

CardiffSeattle

CWL Cardiff Wales - SEA Seattle/Tacoma Intl

CWLSEA

Cardiff Wales

Sun 25/10

17:30-16:45

2 stops30h 15m

Seattle/Tacoma Intl

Sun 1/11

06:00-09:50

2 stops19h 50m

£883

CardiffSeattle

CWL Cardiff Wales - SEA Seattle/Tacoma Intl

CWLSEA

Cardiff Wales

Sun 25/10

17:30-12:47

1 stop26h 17m

Seattle/Tacoma Intl

Sun 1/11

14:35-17:00

1 stop18h 25m

£1,095

CardiffSeattle

CWL Cardiff Wales - SEA Seattle/Tacoma Intl

CWLSEA

Cardiff Wales

Sun 25/10

23:50-21:57

3 stops29h 07m

Seattle/Tacoma Intl

Sun 1/11

07:45-17:00

2 stops25h 15m

£1,132

CardiffSeattle

CWL Cardiff Wales - SEA Seattle/Tacoma Intl

CWLSEA

Cardiff Wales

Fri 15/1

09:00-11:25

2 stops34h 25m

Seattle/Tacoma Intl

Mon 18/1

18:45-08:30

2 stops53h 45m

£1,306

CardiffSeattle

CWL Cardiff Wales - SEA Seattle/Tacoma Intl

CWLSEA

Cardiff Wales

Fri 15/1

17:30-16:53

2 stops31h 23m

Seattle/Tacoma Intl

Mon 18/1

14:25-17:00

1 stop18h 35m

£1,541

CardiffSeattle

CWL Cardiff Wales - SEA Seattle/Tacoma Intl

CWLSEA

Cardiff Wales

Fri 15/1

17:30-11:50

1 stop26h 20m

Seattle/Tacoma Intl

Mon 18/1

14:25-17:00

1 stop18h 35m

£2,067

Flights are sorted by cheapest return flights first.

Deals found on 9/9

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 33h. Airlines will cover a distance of 4709 mi.
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.

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Cheap flights from Cardiff to Seattle from £400

This is the cheapest retur flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 28/9. 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 13 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 13 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 13 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 13 September 2026.

Last-minute flights from Cardiff to SeattleDiscover last-minute flight deals from Cardiff to Seattle. Data last updated 13 September 2026 and is based on user searches.

Discover last-minute flight deals from Cardiff to Seattle. Data last updated 13 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 13 September 2026.

Search for one-way flight options from Cardiff to Seattle. Find affordable one-way fares based on user searches. Data last updated 13 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

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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 13 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 13 September 2026.

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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 13 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 13 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 13 September 2026.

Last-minute flights from Cardiff to Seattle
Discover last-minute flight deals from Cardiff to Seattle. Data last updated 13 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 13 September 2026.