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Portsmouth

$394+ 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 9/13. Fares are subject to change and may not be available on all flights or dates of travel.
IAD — LHR
Jul 28 — Aug 41
Tue 7/28
Tue 8/4
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 June 28, 2026.

This Mytrip deal was found by Cheapflights users on 6/27. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/108:55 pm
IAD
-
SOU
1 stop17h 35m
Aer Lingus
Mon 8/179:20 am
SOU
-
IAD
1 stop11h 25m
Aer Lingus
Deal found 6/27$918
This Mytrip deal was found by Cheapflights users on 6/27. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/103:45 pm
IAD
-
SOU
2 stops22h 45m
Multiple Airlines
Mon 8/178:00 pm
SOU
-
IAD
2 stops24h 24m
Multiple Airlines
Deal found 6/27$922
This Mytrip deal was found by Cheapflights users on 6/24. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/248:30 pm
IAD
-
SOU
3 stops18h 00m
Multiple Airlines
Tue 9/89:15 am
SOU
-
IAD
3 stops40h 20m
Multiple Airlines
Deal found 6/24$928
This Mytrip deal was found by Cheapflights users on 6/27. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/159:45 am
IAD
-
SOU
2 stops28h 45m
Multiple Airlines
Wed 7/228:00 pm
SOU
-
IAD
2 stops25h 13m
Multiple Airlines
Deal found 6/27$966
This Mytrip deal was found by Cheapflights users on 6/24. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 8/238:30 pm
IAD
-
SOU
3 stops30h 00m
Multiple Airlines
Tue 9/81:25 pm
SOU
-
IAD
3 stops30h 45m
Multiple Airlines
Deal found 6/24$981
This Orbitz deal was found by Cheapflights users on 6/24. 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 Orbitz is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 8/235:15 pm
IAD
-
SOU
1 stop10h 25m
Aer Lingus
Tue 9/89:15 am
SOU
-
IAD
1 stop15h 20m
Aer Lingus
Deal found 6/24$1,001
This Kiwi.com deal was found by Cheapflights users on 6/23. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/78:55 pm
IAD
-
SOU
1 stop17h 35m
Aer Lingus
Fri 8/149:20 am
SOU
-
IAD
1 stop11h 25m
Aer Lingus
Deal found 6/23$1,036

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 June 28, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$918
(Mytrip)

One-way from

$394
(Kiwi.com)

Popular in

June

Cheapest in

February

Average price

$1,219
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. 20% potential increase in price ($204 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 5% potential price decrease ($40 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in June 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 June 28, 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

Sun 8/23

5:40 pm-5:35 pm

1 stop18h 55m

Southampton Eastleigh

Tue 9/8

5:20 pm-3:35 pm

1 stop27h 15m

$1,113

Washington, D.C.Southampton

IAD - SOU

IADSOU

Washington, D.C. Dulles Intl

Mon 8/24

6:10 pm-5:35 pm

1 stop18h 25m

Southampton Eastleigh

Mon 9/7

5:20 pm-3:35 pm

1 stop27h 15m

$1,113
Quickest round-trip

Washington, D.C.Southampton

IAD - SOU

IADSOU

Washington, D.C. Dulles Intl

Sun 9/6

11:06 am-8:35 am

2 stops16h 29m

Southampton Eastleigh

Tue 9/15

9:05 am-3:35 pm

1 stop11h 30m

$1,117

Washington, D.C.Southampton

IAD - SOU

IADSOU

Washington, D.C. Dulles Intl

Sun 8/23

6:49 pm-5:35 pm

2 stops17h 46m

Southampton Eastleigh

Tue 9/8

9:05 am-11:14 pm

2 stops19h 09m

$1,127

Washington, D.C.Southampton

IAD - SOU

IADSOU

Washington, D.C. Dulles Intl

Sun 9/6

11:10 am-8:35 am

2 stops16h 25m

Southampton Eastleigh

Tue 9/15

9:05 am-11:23 pm

2 stops19h 18m

$1,127
Cheapest one-way

Washington, D.C.Southampton

IAD - SOU

IADSOU

Washington, D.C. Dulles Intl

Sun 9/13

8:30 pm-8:40 am

3 stops31h 10m

$394

Washington, D.C.Southampton

IAD - SOU

IADSOU

Washington, D.C. Dulles Intl

Sun 8/23

5:15 pm-8:40 am

1 stop10h 25m

$494

Washington, D.C.Southampton

IAD - SOU

IADSOU

Washington, D.C. Dulles Intl

Mon 8/24

8:55 pm-4:50 pm

1 stop14h 55m

$516

Washington, D.C.Southampton

IAD - SOU

IADSOU

Washington, D.C. Dulles Intl

Sun 8/23

8:55 pm-5:45 pm

2 stops15h 50m

$537

Washington, D.C.Southampton

IAD - SOU

IADSOU

Washington, D.C. Dulles Intl

Sun 8/23

12:29 pm-8:45 am

2 stops15h 16m

$539

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/25

Showing 1-10 of 11 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 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 June 28, 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.

Weekly flight availability from Washington, D.C. Dulles Intl Airport to Portsmouth

Explore weekly flight availability from Dulles Intl to Portsmouth. 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 June 28, 2026.

The most flights from IAD to P0R are scheduled on a Friday (28 on average). You will have fewer flight options on Wednesday, which is when the least amount of flights are scheduled (21 on average).

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 June 28, 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
7.3
Good
1,628 reviews

Entertainment

7.0

Comfort

7.2

Food

6.7

Boarding

7.4

Crew

8.1

Overall

7.3

Reviews

1 / 20
8.0
Excellent

Anonymous,Nov 2025

DUB - EDI

Fine except for app. Couldn’t check in online - kept saying I couldn’t check in until the morning after my flight. On second leg I could check in but couldn’t get my boarding pass into my wallet. Thankfully I took a screenshot of it because I couldn’t retrieve it when we boarded - the app prohibited it.
Aer Lingus
7.3
Good
1,628 reviews
Aer Lingus
7.3
Good
1,628 reviews

Entertainment

7.0

Comfort

7.2

Food

6.7

Boarding

7.4

Crew

8.1

Overall

7.3

Reviews

1 / 20
8.0
Excellent

Anonymous,Nov 2025

DUB - EDI

Fine except for app. Couldn’t check in online - kept saying I couldn’t check in until the morning after my flight. On second leg I could check in but couldn’t get my boarding pass into my wallet. Thankfully I took a screenshot of it because I couldn’t retrieve it when we boarded - the app prohibited it.

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 16h 29m. 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 American Airlines (78%), British Airways (78%) or Aer Lingus (77%) 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 $2,356, our data shows the cheapest flight currently is $335. When looking at the most popular route, (Washington, D.C. Dulles Intl - Southampton Eastleigh), you can expect to pay $1,019 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.

See more FAQs

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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 June 28, 2026.
AirlineCheapestAverageFlexibilityOn-time
TAP AIR PORTUGALCheapest$309Average$514FlexibilityNo cancel feeOn-timeN/A
IcelandairCheapest$489Average$677FlexibilityNo cancel feeOn-time76%
Scandinavian AirlinesCheapest$492Average$787FlexibilityNo cancel feeOn-time77%
DeltaCheapest$519Average$879FlexibilityNo cancel feeOn-timeN/A
British AirwaysCheapest$528Average$790FlexibilityNo cancel feeOn-time70%
Virgin AtlanticCheapest$540Average$879FlexibilityNo cancel feeOn-time72%
American AirlinesCheapest$543Average$830FlexibilityNo cancel feeOn-time71%
Aer LingusCheapest$554Average$940FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$557Average$882FlexibilityNo cancel feeOn-time69%
IberiaCheapest$575Average$749FlexibilityNo cancel feeOn-time77%

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