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Cheap flights from Portsmouth to Seattle from £479

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 30/12. Fares are subject to change and may not be available on all flights or dates of travel.
LHR — SEA
18 Aug — 25 Aug1
1 adult
1 adult, Economy, 0 bags

Cheap flight deals from Portsmouth to Seattle

Enter your travel dates to find the best prices.

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 19 July 2026.

Tue 1/917:20
SOU
-
SEA
1 stop26h 27m
Delta
Tue 15/907:15
SEA
-
SOU
2 stops17h 30m
Delta
Deal found 15/7£701
Sat 5/909:15
SOU
-
SEA
2 stops20h 45m
Delta
Fri 18/906:00
SEA
-
SOU
2 stops18h 45m
Delta
Deal found 15/7£705
Sat 22/809:20
SOU
-
SEA
1 stop15h 50m
Aer Lingus
Thu 27/819:10
SEA
-
SOU
1 stop13h 40m
Aer Lingus
Deal found 15/7£728
Sat 22/809:15
SOU
-
SEA
2 stops19h 15m
Delta
Thu 27/807:15
SEA
-
SOU
2 stops17h 30m
Delta
Deal found 15/7£774
Mon 17/809:15
SOU
-
SEA
1 stop34h 22m
Delta
Thu 3/917:45
SEA
-
SOU
1 stop31h 00m
Delta
Deal found 18/7£789
Sat 15/809:15
SOU
-
SEA
2 stops20h 45m
Delta
Sat 5/923:10
SEA
-
SOU
2 stops33h 40m
Delta
Deal found 18/7£793
Sat 22/809:20
SOU
-
SEA
2 stops19h 14m
Multiple Airlines
Thu 27/819:10
SEA
-
SOU
1 stop13h 40m
Multiple Airlines
Deal found 15/7£809
Tue 11/818:05
SOU
-
SEA
1 stop25h 32m
Delta
Wed 2/923:59
SEA
-
SOU
2 stops24h 36m
Delta
Deal found 18/7£830
Wed 12/809:15
SOU
-
SEA
2 stops21h 56m
Delta
Wed 2/923:59
SEA
-
SOU
2 stops24h 36m
Delta
Deal found 18/7£834
Sun 16/817:20
SOU
-
SEA
1 stop31h 50m
British Airways
Sat 5/919:10
SEA
-
SOU
1 stop29h 30m
British Airways
Deal found 18/7£835
Tue 11/809:15
SOU
-
SEA
1 stop15h 55m
British Airways
Fri 4/913:30
SEA
-
SOU
2 stops36h 15m
British Airways
Deal found 18/7£836
Mon 17/820:00
SOU
-
SEA
1 stop29h 10m
British Airways
Sat 5/920:20
SEA
-
SOU
2 stops28h 05m
British Airways
Deal found 18/7£837

Find flight deals from Portsmouth to Seattle

Keep the following information in mind while searching for Portsmouth to Seattle flight deals. Data was last updated 19 July 2026.

Round-trip from

£701

One-way from

£479

Popular in

December

Cheapest in

February

Average price

£627
Delta
  • Delta
  • 1/9-14/9
  • 3 total stops
  • 51h 13m total
  • Portsmouth to Seattle
Search Deals
British Airways
  • British Airways
  • 27/12
  • 1 total stop
  • 17h 00m total
  • Portsmouth to Seattle
Search Deals
High demand for flights, 0% potential price rise
Search Deals
Cheapest flight prices on average. 1% potential price decrease (£6 potential savings vs. average return price).
Search Deals
Average for round-trip flights in July 2026
Search Deals

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 19 July 2026.
Use the filters below to find and compare flights from Portsmouth to Seattle that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest return flight

SouthamptonSeattle

SOU - SEA

SOUSEA

Southampton Eastleigh

Mon 7/9

17:20-11:47

1 stop26h 27m

Seattle/Tacoma Intl

Mon 14/9

23:59-16:50

2 stops32h 51m

£701

SouthamptonSeattle

SOU - SEA

SOUSEA

Southampton Eastleigh

Thu 3/9

17:20-11:47

1 stop26h 27m

Seattle/Tacoma Intl

Fri 18/9

06:00-08:45

2 stops18h 45m

£701

SouthamptonSeattle

SOU - SEA

SOUSEA

Southampton Eastleigh

Mon 7/9

17:20-11:47

1 stop26h 27m

Seattle/Tacoma Intl

Thu 17/9

23:05-08:45

2 stops25h 40m

£701

SouthamptonSeattle

SOU - SEA

SOUSEA

Southampton Eastleigh

Thu 3/9

09:05-11:47

1 stop34h 42m

Seattle/Tacoma Intl

Thu 17/9

06:00-08:35

2 stops18h 35m

£701

SouthamptonSeattle

SOU - SEA

SOUSEA

Southampton Eastleigh

Tue 1/9

09:05-11:47

1 stop34h 42m

Seattle/Tacoma Intl

Sat 12/9

09:30-08:45

2 stops15h 15m

£701

SouthamptonSeattle

SOU - SEA

SOUSEA

Southampton Eastleigh

Sat 5/9

09:15-22:00

2 stops20h 45m

Seattle/Tacoma Intl

Thu 17/9

06:00-08:35

2 stops18h 35m

£705

SouthamptonSeattle

SOU - SEA

SOUSEA

Southampton Eastleigh

Sat 22/8

09:15-20:30

2 stops19h 15m

Seattle/Tacoma Intl

Thu 27/8

07:15-08:45

2 stops17h 30m

£774

SouthamptonSeattle

SOU - SEA

SOUSEA

Southampton Eastleigh

Tue 11/8

09:15-16:27

1 stop15h 12m

Seattle/Tacoma Intl

Sat 5/9

17:45-08:35

1 stop30h 50m

£789
Fastest return journey

SouthamptonSeattle

SOU - SEA

SOUSEA

Southampton Eastleigh

Sat 22/8

09:20-20:34

2 stops19h 14m

Seattle/Tacoma Intl

Thu 27/8

19:10-16:50

1 stop13h 40m

£809

SouthamptonSeattle

SOU - SEA

SOUSEA

Southampton Eastleigh

Thu 13/8

18:05-11:37

1 stop25h 32m

Seattle/Tacoma Intl

Wed 2/9

23:59-08:35

2 stops24h 36m

£830

Flights are sorted by cheapest return flights first.

Deals found on 14/7

Showing 1-10 of 20 resultsSorted by cheapest first
1
2

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 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 19 July 2026.

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.

Weekly flight availability from Portsmouth to Seattle

Explore weekly flight availability from Portsmouth to Seattle. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated 19 July 2026.

The most flights from P0R to SEA are scheduled on a Tuesday (24 on average). You will have fewer flight options on Sunday, which is when the least amount of flights are scheduled (18 on average).

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. 13 airlines have flights to Seattle/Tacoma Intl from Portsmouth on a regular basis.

  • How long is the flight from Portsmouth to Seattle?

    For as low as £701, Delta can have you in Seattle from Portsmouth in 26h 27m. The distance from Portsmouth to Seattle is about 4787 mi.

  • 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: Scandinavian Airlines (88%), KLM (79%), Air France( 79%).

  • What are the cheapest flights from Portsmouth to Seattle?

    Looking for the cheapest flight from Portsmouth to Seattle? While on average our users pay £1,545, our data indicates the cheapest price to be £334. The most popular route (Southampton Eastleigh - Seattle/Tacoma Intl), is priced around £834.

  • 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.

See more FAQs

Travelling to a place near Seattle?

Book flights to Seattle if you plan to visit one of these locations
Tacoma
Federal Way
SeaTac

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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 19 July 2026.
AirlineCheapestAverageFlexibilityOn-time
LufthansaCheapest£334Average£526FlexibilityNo cancel feeOn-time76%
Search Lufthansa flights
IcelandairCheapest£340Average£500FlexibilityNo cancel feeOn-time76%
Search Icelandair flights
Aer LingusCheapest£390Average£617FlexibilityNo cancel feeOn-timeN/A
Search Aer Lingus flights
Virgin AtlanticCheapest£423Average£584FlexibilityNo cancel feeOn-time72%
Search Virgin Atlantic flights
United AirlinesCheapest£429Average£639FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
KLMCheapest£436Average£614FlexibilityNo cancel feeOn-time75%
Search KLM flights
DeltaCheapest£440Average£643FlexibilityNo cancel feeOn-timeN/A
Search Delta flights
Air FranceCheapest£449Average£636FlexibilityNo cancel feeOn-time77%
Search Air France flights
British AirwaysCheapest£456Average£637FlexibilityNo cancel feeOn-time70%
Search British Airways flights
Alaska AirlinesCheapest£469Average£595FlexibilityNo cancel feeOn-time75%
Search Alaska Airlines flights

Fly with Cheapflights

Find the best flight deals on Cheapflights, where travellers can enjoy low prices and a wide availability of flights to their desired destinations.

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

900+ travel sites are searched through when a user searches for a flight using Cheapflights. From the search interface, users can use filters to choose airlines, airports, flight times, cabin classes and more to their preference. Book your flight to Seattle from Portsmouth today with Cheapflights!

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

Cheapflights taps into our reliable network of hundreds of airlines and travel agencies to find the best deals for flights from Portsmouth to Seattle for you. Better yet — we are completely free to use.

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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