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Portsmouth

$329+ 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 8/4. Fares are subject to change and may not be available on all flights or dates of travel.
IAD — LHR
Mar 7 — Mar 141
Sat 3/7
Sat 3/14
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 February 5, 2026.

This Mytrip deal was found by Cheapflights users on 2/5. 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 3/228:40 pm
IAD
-
SOU
2 stops16h 35m
Multiple Airlines
Sun 3/2910:00 am
SOU
-
IAD
2 stops14h 20m
Multiple Airlines
Deal found 2/5$767
This Delta deal was found by Cheapflights users on 2/3. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/197:05 pm
IAD
-
SOU
1 stop17h 55m
Delta
Thu 3/268:50 am
SOU
-
IAD
1 stop12h 15m
Delta
Deal found 2/3$777
This Delta deal was found by Cheapflights users on 2/2. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 3/16:05 pm
IAD
-
SOU
1 stop18h 00m
Delta
Fri 3/138:50 am
SOU
-
IAD
1 stop12h 15m
Delta
Deal found 2/2$779
This Delta deal was found by Cheapflights users on 2/2. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 3/17:00 am
IAD
-
SOU
2 stops20h 20m
Delta
Tue 3/108:50 am
SOU
-
IAD
1 stop12h 15m
Delta
Deal found 2/2$783
This Delta deal was found by Cheapflights users on 2/3. 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 Delta 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
Delta
Mon 9/79:05 am
SOU
-
IAD
1 stop11h 30m
Delta
Deal found 2/3$792
This Delta deal was found by Cheapflights users on 2/1. 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 Delta 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
Delta
Tue 9/89:05 am
SOU
-
IAD
1 stop11h 30m
Delta
Deal found 2/1$794
This Delta deal was found by Cheapflights users on 2/2. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/197:05 pm
IAD
-
SOU
1 stop17h 55m
Delta
Wed 4/89:05 am
SOU
-
IAD
1 stop11h 30m
Delta
Deal found 2/2$795
This KLM deal was found by Cheapflights users on 2/3. 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.
Fri 3/207:05 pm
IAD
-
SOU
1 stop9h 45m
KLM
Fri 3/275:35 pm
SOU
-
IAD
1 stop27h 30m
KLM
Deal found 2/3$842

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 February 5, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$777
(Delta)

One-way from

$329
(Kiwi.com)

Popular in

June

Cheapest in

September

Average price

$643
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 ($95 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 February 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 February 5, 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

Dulles Intl

Fly to

Portsmouth

Route

Depart

Return

Price

Washington, D.C.Southampton

IAD - SOU

IADSOU

Washington, D.C. Dulles Intl

Sun 3/22

7:05 pm-5:05 pm

1 stop18h 00m

Southampton Eastleigh

Sun 3/29

5:20 pm-3:35 pm

1 stop27h 15m

$777

Washington, D.C.Southampton

IAD - SOU

IADSOU

Washington, D.C. Dulles Intl

Tue 3/3

6:05 pm-5:00 pm

1 stop17h 55m

Southampton Eastleigh

Mon 3/9

5:40 pm-5:05 pm

1 stop27h 25m

$779

Washington, D.C.Southampton

IAD - SOU

IADSOU

Washington, D.C. Dulles Intl

Tue 3/3

6:05 pm-5:00 pm

1 stop17h 55m

Southampton Eastleigh

Thu 3/12

8:50 am-5:05 pm

1 stop12h 15m

$779

Washington, D.C.Southampton

IAD - SOU

IADSOU

Washington, D.C. Dulles Intl

Wed 3/4

6:00 am-8:20 am

2 stops21h 20m

Southampton Eastleigh

Mon 3/9

5:40 pm-5:05 pm

1 stop27h 25m

$783

Washington, D.C.Southampton

IAD - SOU

IADSOU

Washington, D.C. Dulles Intl

Sun 3/1

12:24 pm-5:05 pm

2 stops23h 41m

Southampton Eastleigh

Wed 3/11

5:35 pm-5:05 pm

1 stop27h 30m

$783

Washington, D.C.Southampton

IAD - SOU

IADSOU

Washington, D.C. Dulles Intl

Mon 3/2

3:42 pm-5:00 pm

2 stops20h 18m

Southampton Eastleigh

Tue 3/10

5:35 pm-5:05 pm

1 stop27h 30m

$783

Washington, D.C.Southampton

IAD - SOU

IADSOU

Washington, D.C. Dulles Intl

Thu 3/19

1:19 pm-8:20 am

2 stops15h 01m

Southampton Eastleigh

Thu 3/26

8:50 am-5:05 pm

1 stop12h 15m

$783

Washington, D.C.Southampton

IAD - SOU

IADSOU

Washington, D.C. Dulles Intl

Thu 3/19

1:19 pm-8:20 am

2 stops15h 01m

Southampton Eastleigh

Wed 4/8

9:05 am-10:59 pm

2 stops18h 54m

$809

Washington, D.C.Southampton

IAD - SOU

IADSOU

Washington, D.C. Dulles Intl

Fri 3/20

7:05 pm-8:50 am

1 stop9h 45m

Southampton Eastleigh

Fri 3/27

5:35 pm-5:05 pm

1 stop27h 30m

$842

Washington, D.C.Southampton

IAD - SOU

IADSOU

Washington, D.C. Dulles Intl

Fri 3/6

6:05 pm-8:50 am

1 stop9h 45m

Southampton Eastleigh

Fri 3/13

8:50 am-5:05 pm

1 stop12h 15m

$898

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/3

Showing 1-10 of 17 results
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 $336). Flying from Washington, D.C. Dulles Intl Airport to Portsmouth in June is currently the most expensive (average of $737). 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 February 5, 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 February 5, 2026.

The most flights from IAD to P0R are scheduled on a Wednesday (26 on average). You will have fewer flight options on Tuesday, which is when the least amount of flights are scheduled (20 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 February 5, 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
1,445 reviews

Overall

7.2

Crew

8.0

Entertainment

6.9

Comfort

7.1

Food

6.6

Boarding

7.4

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
1,445 reviews
Aer Lingus
7.2
Good
1,445 reviews

Overall

7.2

Crew

8.0

Entertainment

6.9

Comfort

7.1

Food

6.6

Boarding

7.4

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 17h 55m. KLM provides one of the quickest options available for as low as $779. 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 (83%), Aer Lingus (83%) or Finnair (83%) 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 $2,137, our data shows the cheapest flight currently is $258. When looking at the most popular route, (Washington, D.C. Dulles Intl - Southampton Eastleigh), you can expect to pay $792 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 $336). Flying from Washington, D.C. Dulles Intl Airport to Portsmouth in June is currently the most expensive (average of $737). 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.

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Alternative routes for Dulles Intl to Portsmouth

See prices for flight routes from nearby airports that may be better suited for you.
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Baltimore to Newquay flights
Reagan-National to Bristol flights
Reagan-National to Newquay flights
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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 February 5, 2026.
AirlineCheapestAverageFlexibilityOn-time
TAP AIR PORTUGALCheapest$411Average$550FlexibilityNo cancel feeOn-timeN/A
IcelandairCheapest$415Average$622FlexibilityNo cancel feeOn-time76%
Air FranceCheapest$442Average$868FlexibilityNo cancel feeOn-time77%
LufthansaCheapest$447Average$1,138FlexibilityNo cancel feeOn-time76%
Scandinavian AirlinesCheapest$454Average$597FlexibilityNo cancel feeOn-time77%
KLMCheapest$488Average$691FlexibilityNo cancel feeOn-time75%
DeltaCheapest$516Average$783FlexibilityNo cancel feeOn-timeN/A
British AirwaysCheapest$540Average$751FlexibilityNo cancel feeOn-time70%
Air CanadaCheapest$549Average$758FlexibilityNo cancel feeOn-time67%
Virgin AtlanticCheapest$557Average$786FlexibilityNo cancel feeOn-time72%

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