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Cheap flights from Portsmouth to Seattle from £478

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 7/9. Fares are subject to change and may not be available on all flights or dates of travel.
LHR — SEA
2 Apr — 9 Apr1
1 adult

Cheap flight deals from Portsmouth to Seattle

Keep the following information in mind while searching for Portsmouth to Seattle flight deals. Data was last updated 28 March 2025.

Round-trip from

£602

One-way from

£478

Popular in

August

Cheapest in

January

Average price

£525
Delta
  • Delta
  • 1/9-16/9
  • 3 total stops
  • 43h 35m total
  • Portsmouth to Seattle
Search Deals
Aer Lingus
  • Aer Lingus
  • 7/9
  • 1 total stop
  • 28h 59m total
  • Portsmouth to Seattle
Search Deals
Highest demand for flights based on searches. 15% potential increase in price (£85 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease (£14 potential savings vs. average return price).
Search Deals
Average for round-trip flights in March 2025
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Find flight deals from Portsmouth to Seattle

Cheapest flights from Portsmouth to Seattle
Explore the most affordable flight options available from Portsmouth to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 28 March 2025.

Mon 1/917:35SOU - SEA
1 stop26h 10mDelta
Tue 16/907:20SEA - SOU
2 stops17h 25mDelta
Deal found 27/3£602
Fri 9/517:35SOU - SEA
1 stop26h 05mKLM
Tue 13/518:10SEA - SOU
1 stop14h 50mKLM
Deal found 27/3£603
Fri 9/520:00SOU - SEA
2 stops29h 50mMultiple Airlines
Tue 13/507:05SEA - SOU
3 stops28h 25mMultiple Airlines
Deal found 27/3£926

Cheapflights Fare Finder

Customise your flight search to find flights from Portsmouth to Seattle 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 858,174 searches. Data last updated 28 March 2025.
Use the filters below to find and compare flights from Portsmouth to Seattle that are best for you.

Fly from

Portsmouth

Fly to

Seattle

Route

Depart

Return

Price

SouthamptonSeattle

SOU - SEA

SOUSEA

Southampton Eastleigh

Mon 1/9

17:35-11:45

1 stop26h 10m

Seattle/Tacoma Intl

Tue 16/9

07:20-08:45

2 stops17h 25m

£602

SouthamptonSeattle

SOU - SEA

SOUSEA

Southampton Eastleigh

Fri 9/5

17:35-11:40

1 stop26h 05m

Seattle/Tacoma Intl

Tue 13/5

18:10-17:00

1 stop14h 50m

£603

SouthamptonSeattle

SOU - SEA

SOUSEA

Southampton Eastleigh

Fri 9/5

20:00-17:50

2 stops29h 50m

Seattle/Tacoma Intl

Tue 13/5

07:05-19:30

3 stops28h 25m

£926

SouthamptonSeattle

SOU - SEA

SOUSEA

Southampton Eastleigh

Sun 7/9

20:00-16:59

1 stop28h 59m

£478

Flights are sorted by cheapest return flights first.

Deals found on 27/3

Best time to book a flight from Portsmouth to Seattle

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

Cheapflights Insights

Everything you need to know about your flight from Portsmouth to Seattle

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

Currently, January is the cheapest month in which you can book a flight from Portsmouth to Seattle (average of £622). Flying from Portsmouth to Seattle in July is currently the most expensive (average of £946). 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 time of day to fly from P0R to SEA?

Find hourly flight availability from Portsmouth to Seattle. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated 28 March 2025.

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

Rainfall in Seattle by month

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

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.

Temperature in Seattle by month

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

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).

Reviews of airlines servicing Seattle

Get insights into the airlines that provide service to Seattle. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Seattle. Reviews last updated 28 March 2025.
Delta
8.0
Very Good
7,896 reviews
Check prices

Comfort

8.0

Entertainment

7.9

Crew

8.5

Food

7.3

Overall

8.0

Boarding

8.2

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
Delta
8.0
Very Good
7,896 reviews
Delta
8.0
Very Good
7,896 reviews
Check prices

Comfort

8.0

Entertainment

7.9

Crew

8.5

Food

7.3

Overall

8.0

Boarding

8.2

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
KLM
7.8
Good
1,321 reviews
Delta
8.0
Very Good
7,896 reviews
Check prices

Comfort

8.0

Entertainment

7.9

Crew

8.5

Food

7.3

Overall

8.0

Boarding

8.2

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
Aer Lingus
7.0
Good
1,062 reviews
Delta
8.0
Very Good
7,896 reviews
Check prices

Comfort

8.0

Entertainment

7.9

Crew

8.5

Food

7.3

Overall

8.0

Boarding

8.2

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

Related info for your journey

Find useful and relevant information for your journey from Portsmouth to Seattle. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airport do you fly into for flights to Seattle from Portsmouth?

    For a flight from Portsmouth to Seattle, you will be flying into Seattle/Tacoma Intl. Seattle/Tacoma Intl (SEA) is just 11.4 mi from the center of the city. Seattle/Tacoma Intl is the only Seattle airport and it handles 0 inbound flights from Portsmouth per day. 12 airlines have flights to Seattle/Tacoma Intl from Portsmouth on a regular basis.

  • What are the most reliable airlines from Portsmouth to Seattle?

    Before booking your flight to Seattle from Portsmouth, check out the most reliable airlines to get you to your destination on time: Aeromexico (98%), Singapore Airlines (98%), KLM( 92%).

  • What are the cheapest flights from Portsmouth to Seattle?

    Looking for the cheapest flight from Portsmouth to Seattle? While on average our users pay £1,884, our data indicates the cheapest price to be £481. The most popular route (Southampton Eastleigh - Seattle/Tacoma Intl), is priced around £582.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Portsmouth 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.

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

    Currently, January is the cheapest month in which you can book a flight from Portsmouth to Seattle (average of £622). Flying from Portsmouth to Seattle in July is currently the most expensive (average of £946). 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

Travelling to a place near Portsmouth?

Book flights to Portsmouth if you plan to visit one of these locations
Tacoma
Leavenworth
Bothell

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Alternative routes for Portsmouth to Seattle

See prices for flight routes from nearby airports that may be better suited for you.
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Top 10 airlines flying from Portsmouth to Seattle

Discover the top 10 airlines that operate flights from Portsmouth to Seattle. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 858,174 searches. Data last updated 28 March 2025.
AirlineCheapestAverageFlexibilityOn-time
Aer LingusCheapest£8Average£693FlexibilityNo cancel feeOn-timeN/A
Search Aer Lingus flights
IcelandairCheapest£338Average£529FlexibilityNo cancel feeOn-time76%
Search Icelandair flights
Air FranceCheapest£400Average£593FlexibilityNo cancel feeOn-time77%
Search Air France flights
LufthansaCheapest£410Average£522FlexibilityNo cancel feeOn-time76%
Search Lufthansa flights
United AirlinesCheapest£421Average£647FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
KLMCheapest£422Average£612FlexibilityNo cancel feeOn-time75%
Search KLM flights
FinnairCheapest£430Average£594FlexibilityNo cancel feeOn-time76%
Search Finnair flights
DeltaCheapest£446Average£638FlexibilityNo cancel feeOn-timeN/A
Search Delta flights
British AirwaysCheapest£450Average£588FlexibilityNo cancel feeOn-time70%
Search British Airways flights
Virgin AtlanticCheapest£469Average£587FlexibilityNo cancel feeOn-time72%
Search Virgin Atlantic flights

Fly with Cheapflights

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

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

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

Yes, we can. To see specific flights from Portsmouth to Seattle with no change fees, users can toggle flexible booking options after using the search form above to find flights.

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

Yes, Cheapflights has a feature called Price Alert, which notifies users when flight prices change. Track prices for your flight to Seattle from Portsmouth today and book when prices fit your budget.

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