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Portsmouth

$634+ Cheap flights from Dulles Intl (IAD) to Portsmouth, England

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 4/1. Fares are subject to change and may not be available on all flights or dates of travel.
IAD — LHR
Apr 26 — May 31
Sun 4/26
Sun 5/3
1 adult, Economy
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Cheap flight deals from Dulles Intl to Portsmouth

Cheapest flights from Dulles Intl to Portsmouth
Explore the most affordable flight options available from Dulles Intl to Portsmouth. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 27, 2026.

This Kiwi.com deal was found by Cheapflights users on 3/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/178:45 pm
IAD
-
SOU
1 stop15h 05m
Multiple Airlines
Tue 10/66:10 pm
SOU
-
IAD
2 stops30h 05m
Multiple Airlines
Deal found 3/27$1,034
This Kiwi.com deal was found by Cheapflights users on 3/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/115:15 pm
IAD
-
SOU
1 stop10h 25m
Multiple Airlines
Mon 5/187:20 pm
SOU
-
IAD
2 stops24h 50m
Multiple Airlines
Deal found 3/26$1,061
This KLM deal was found by Cheapflights users on 3/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/246:10 pm
IAD
-
SOU
1 stop9h 35m
KLM
Mon 9/75:20 pm
SOU
-
IAD
1 stop27h 15m
KLM
Deal found 3/23$1,082
This KLM deal was found by Cheapflights users on 3/23. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/126:10 pm
IAD
-
SOU
1 stop18h 25m
KLM
Wed 8/269:15 am
SOU
-
IAD
1 stop11h 20m
KLM
Deal found 3/23$1,112
This Kiwi.com deal was found by Cheapflights users on 3/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/811:20 pm
IAD
-
SOU
2 stops27h 35m
Multiple Airlines
Fri 5/158:00 pm
SOU
-
IAD
1 stop24h 45m
Multiple Airlines
Deal found 3/24$1,116
This Virgin Atlantic deal was found by Cheapflights users on 3/25. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Virgin Atlantic is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/66:10 pm
IAD
-
SOU
1 stop9h 25m
Virgin Atlantic
Tue 5/129:05 am
SOU
-
IAD
1 stop11h 30m
Virgin Atlantic
Deal found 3/25$1,117
This KLM deal was found by Cheapflights users on 3/26. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/116:10 pm
IAD
-
SOU
1 stop9h 25m
KLM
Mon 5/185:20 pm
SOU
-
IAD
1 stop27h 15m
KLM
Deal found 3/26$1,118

Find flight deals from Dulles Intl to Portsmouth

Keep the following information in mind while searching for Dulles Intl to Portsmouth flight deals. Data was last updated March 27, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$1,034
(Kiwi.com)

One-way from

$634
(Delta)

Popular in

June

Cheapest in

September

Average price

$702
Provider with most accurate pricing for Washington, D.C. (WAS)-London (LON) flight deals.
Search Deals
Provider most trusted by Cheapflights users for Washington, D.C. (WAS)-London (LON) flights.
Search Deals
From Washington, D.C. Dulles Intl to Portsmouth
Search Deals
One-way flight from Washington, D.C. Dulles Intl to Portsmouth
Search Deals
Highest demand for flights based on searches. 11% potential increase in price ($100 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($20 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in March 2026
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Dulles Intl to Portsmouth 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 2,558,603 searches. Data last updated March 27, 2026.
Use the filters below to find and compare flights from Washington, D.C. Dulles Intl Airport to Portsmouth that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

Washington, D.C.Southampton

IAD - SOU

IADSOU

Washington, D.C. Dulles Intl

Mon 8/24

6:10 pm-8:45 am

1 stop9h 35m

Southampton Eastleigh

Mon 9/7

5:20 pm-3:35 pm

1 stop27h 15m

$1,110

Washington, D.C.Southampton

IAD - SOU

IADSOU

Washington, D.C. Dulles Intl

Wed 8/12

6:10 pm-5:35 pm

1 stop18h 25m

Southampton Eastleigh

Wed 8/26

9:15 am-3:35 pm

1 stop11h 20m

$1,112
Quickest round-trip

Washington, D.C.Southampton

IAD - SOU

IADSOU

Washington, D.C. Dulles Intl

Wed 5/6

6:10 pm-8:35 am

1 stop9h 25m

Southampton Eastleigh

Tue 5/12

9:05 am-3:35 pm

1 stop11h 30m

$1,117

Washington, D.C.Southampton

IAD - SOU

IADSOU

Washington, D.C. Dulles Intl

Mon 5/11

6:10 pm-8:35 am

1 stop9h 25m

Southampton Eastleigh

Mon 5/18

5:20 pm-3:35 pm

1 stop27h 15m

$1,118

Washington, D.C.Southampton

IAD - SOU

IADSOU

Washington, D.C. Dulles Intl

Wed 8/12

12:30 pm-8:45 am

2 stops15h 15m

Southampton Eastleigh

Wed 8/26

9:15 am-3:35 pm

1 stop11h 20m

$1,122

Washington, D.C.Southampton

IAD - SOU

IADSOU

Washington, D.C. Dulles Intl

Sat 8/29

1:00 pm-8:45 am

2 stops14h 45m

Southampton Eastleigh

Mon 9/7

5:20 pm-3:35 pm

1 stop27h 15m

$1,149

Washington, D.C.Southampton

IAD - SOU

IADSOU

Washington, D.C. Dulles Intl

Mon 5/11

10:11 am-8:35 am

2 stops17h 24m

Southampton Eastleigh

Mon 5/18

9:05 am-9:24 pm

2 stops17h 19m

$1,182
Cheapest one-way
Quickest one-way

Washington, D.C.Southampton

IAD - SOU

IADSOU

Washington, D.C. Dulles Intl

Wed 4/1

6:10 pm-8:35 am

1 stop9h 25m

$634

Washington, D.C.Southampton

IAD - SOU

IADSOU

Washington, D.C. Dulles Intl

Thu 6/11

8:45 pm-7:30 pm

1 stop17h 45m

$665

Washington, D.C.Southampton

IAD - SOU

IADSOU

Washington, D.C. Dulles Intl

Sat 4/4

8:16 pm-8:35 am

2 stops31h 19m

$688

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/24

Showing 1-10 of 12 resultsSorted by cheapest first
1
2

Best time to book a flight from Dulles Intl to Portsmouth

Have a flexible travel schedule? Discover the best time to fly to Portsmouth from Dulles Intl 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 Washington, D.C. Dulles Intl Airport to Portsmouth

What is the cheapest month to book a flight from Washington, D.C. Dulles Intl Airport to Portsmouth?

Currently, March is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to Portsmouth (average of $363). Flying from Washington, D.C. Dulles Intl Airport to Portsmouth in June is currently the most expensive (average of $726). 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 IAD to P0R?

Find hourly flight availability from Dulles Intl to Portsmouth. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated March 27, 2026.

One of the essential ways to save on airfare from Washington, D.C. Dulles Intl Airport to Portsmouth is to remain as flexible as possible. Flights that are at noon tend to be the most expensive. A flight in the morning could potentially save you up to 50% on airfare.

Reviews of airlines servicing Portsmouth

Get insights into the airlines that provide service to Portsmouth. 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 Portsmouth. Reviews last updated March 27, 2026.
Read through reviews of airlines operating flights from Washington, D.C. Dulles Intl Airport to Portsmouth, such as Aer Lingus. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Aer Lingus
7.2
Good
1,491 reviews

Boarding

7.4

Overall

7.2

Entertainment

7.0

Comfort

7.2

Food

6.6

Crew

8.1

Reviews

1 / 20
10.0
Excellent

Anonymous,Jan 2026

SFO - DUB

The boarding went smoothly, the crew were great and helped me with an extra pillow, the food was good including complementary wine with dinner (economy seating), and I was able to sleep. The flight arrived early which helped with connections. Overall a great experience.
Aer Lingus
7.2
Good
1,491 reviews
Aer Lingus
7.2
Good
1,491 reviews

Boarding

7.4

Overall

7.2

Entertainment

7.0

Comfort

7.2

Food

6.6

Crew

8.1

Reviews

1 / 20
10.0
Excellent

Anonymous,Jan 2026

SFO - DUB

The boarding went smoothly, the crew were great and helped me with an extra pillow, the food was good including complementary wine with dinner (economy seating), and I was able to sleep. The flight arrived early which helped with connections. Overall a great experience.

Related info for your journey

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

  • How long is the flight from Washington, D.C. Dulles Intl Airport to Portsmouth?

    A quick flight from Washington, D.C. Dulles Intl Airport to Portsmouth can take about 9h 25m. KLM provides one of the quickest options available for as low as $1,117. There are 3639 mi between Washington, D.C. Dulles Intl Airport and Portsmouth. This flight may include one or multiple stops.

  • What are the most reliable airlines from Washington, D.C. Dulles Intl Airport to Portsmouth?

    Consider KLM (90%), Air France (90%) or Delta (90%) when booking your flight. These represent the most reliable airlines when flying from Washington, D.C. Dulles Intl Airport to Portsmouth.

  • What are the cheapest flights from Washington, D.C. Dulles Intl Airport to Portsmouth?

    While on average a flight from Washington, D.C. Dulles Intl Airport to Portsmouth is generally $2,284, our data shows the cheapest flight currently is $347. When looking at the most popular route, (Washington, D.C. Dulles Intl - Southampton Eastleigh), you can expect to pay $1,061 for that flight.

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

    Yes. In addition to deals on Dulles Intl to Portsmouth flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Dulles Intl to Portsmouth?

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

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

    Yes. Cheapflights offers flight deals from Dulles Intl to Portsmouth 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 Washington, D.C. Dulles Intl Airport to Portsmouth?

    Currently, March is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to Portsmouth (average of $363). Flying from Washington, D.C. Dulles Intl Airport to Portsmouth in June is currently the most expensive (average of $726). 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

Browse thousands of different options on Cheapflights for your next trip

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Top 10 airlines flying from Dulles Intl to Portsmouth

Discover the top 10 airlines that operate flights from Dulles Intl to Portsmouth. 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 2,558,603 searches. Data last updated March 27, 2026.
AirlineCheapestAverageFlexibilityOn-time
TAP AIR PORTUGALCheapest$395Average$549FlexibilityNo cancel feeOn-timeN/A
IcelandairCheapest$398Average$608FlexibilityNo cancel feeOn-time76%
Scandinavian AirlinesCheapest$454Average$598FlexibilityNo cancel feeOn-time77%
DeltaCheapest$530Average$834FlexibilityNo cancel feeOn-timeN/A
British AirwaysCheapest$538Average$742FlexibilityNo cancel feeOn-time70%
Virgin AtlanticCheapest$552Average$795FlexibilityNo cancel feeOn-time72%
United AirlinesCheapest$558Average$859FlexibilityNo cancel feeOn-time69%
Aer LingusCheapest$561Average$930FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$572Average$800FlexibilityNo cancel feeOn-time71%
IberiaCheapest$574Average$739FlexibilityNo cancel feeOn-time77%

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