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Cheap flights from Portsmouth to Washington, D.C. Dulles Intl Airport from £371

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 24/11. Fares are subject to change and may not be available on all flights or dates of travel.
LHR — IAD
16 Jul — 23 Jul1
1 adult
1 adult, Economy, 0 bags

Cheap flight deals from Portsmouth to Dulles Intl

Enter your travel dates to find the best prices.

Cheapest flights from Portsmouth to Dulles Intl
Explore the most affordable flight options available from Portsmouth to Dulles Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 16 June 2026.

Wed 8/709:20
SOU
-
IAD
1 stop14h 55m
British Airways
Fri 24/717:15
IAD
-
SOU
1 stop18h 35m
British Airways
Deal found 11/6£507
Thu 29/1009:20
SOU
-
IAD
1 stop15h 10m
British Airways
Thu 5/1117:05
IAD
-
SOU
1 stop10h 35m
British Airways
Deal found 11/6£509
Tue 1/920:00
SOU
-
IAD
1 stop28h 25m
British Airways
Fri 11/920:55
IAD
-
SOU
1 stop14h 55m
British Airways
Deal found 12/6£517
Sun 27/920:00
SOU
-
IAD
1 stop24h 45m
British Airways
Sun 4/1017:15
IAD
-
SOU
1 stop10h 25m
British Airways
Deal found 11/6£520
Mon 6/720:00
SOU
-
IAD
1 stop24h 45m
British Airways
Sat 8/817:15
IAD
-
SOU
1 stop18h 35m
British Airways
Deal found 13/6£526

Find flight deals from Portsmouth to Dulles Intl

Keep the following information in mind while searching for Portsmouth to Dulles Intl flight deals. Data was last updated 16 June 2026.

Round-trip from

£507

One-way from

£371

Popular in

June

Cheapest in

February

Average price

£590
British Airways
  • British Airways
  • 8/7-24/7
  • 2 total stops
  • 33h 30m total
  • Portsmouth to Washington, D.C.
Search Deals
Aer Lingus
  • Aer Lingus
  • 24/11
  • 1 total stop
  • 15h 10m total
  • Portsmouth to Washington, D.C.
Search Deals
Highest demand for flights based on searches. 9% potential increase in price (£42 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease (£5 potential savings vs. average return price).
Search Deals
Average for round-trip flights in June 2026
Search Deals

Cheapflights Fare Finder

 
Customise your flight search to find flights from Portsmouth to Dulles Intl 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 16 June 2026.
Use the filters below to find and compare flights from Portsmouth to Washington, D.C. Dulles Intl Airport that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest return flight

SouthamptonWashington, D.C.

SOU - IAD

SOUIAD

Southampton Eastleigh

Wed 8/7

09:20-19:15

1 stop14h 55m

Washington, D.C. Dulles Intl

Fri 24/7

17:15-16:50

1 stop18h 35m

£507
Fastest return journey

SouthamptonWashington, D.C.

SOU - IAD

SOUIAD

Southampton Eastleigh

Thu 29/10

09:20-20:30

1 stop15h 10m

Washington, D.C. Dulles Intl

Thu 5/11

17:05-08:40

1 stop10h 35m

£508

SouthamptonWashington, D.C.

SOU - IAD

SOUIAD

Southampton Eastleigh

Sun 27/9

20:00-15:45

1 stop24h 45m

Washington, D.C. Dulles Intl

Sun 4/10

17:15-08:40

1 stop10h 25m

£520

SouthamptonWashington, D.C.

SOU - IAD

SOUIAD

Southampton Eastleigh

Mon 6/7

20:00-15:45

1 stop24h 45m

Washington, D.C. Dulles Intl

Sat 8/8

17:15-16:50

1 stop18h 35m

£526

SouthamptonWashington, D.C.

SOU - IAD

SOUIAD

Southampton Eastleigh

Thu 29/10

08:40-23:02

2 stops18h 22m

Washington, D.C. Dulles Intl

Thu 5/11

19:59-17:00

2 stops16h 01m

£570

SouthamptonWashington, D.C.

SOU - IAD

SOUIAD

Southampton Eastleigh

Tue 1/9

09:05-23:26

2 stops19h 21m

Washington, D.C. Dulles Intl

Fri 11/9

17:40-08:45

1 stop10h 05m

£570

SouthamptonWashington, D.C.

SOU - IAD

SOUIAD

Southampton Eastleigh

Thu 29/10

08:40-23:02

2 stops18h 22m

Washington, D.C. Dulles Intl

Thu 5/11

10:05-08:10

2 stops17h 05m

£571
Cheapest one-way
Fastest single journey

SouthamptonWashington, D.C.

SOU - IAD

SOUIAD

Southampton Eastleigh

Mon 23/11

09:20-15:35

1 stop11h 15m

£430

SouthamptonWashington, D.C.

SOU - IAD

SOUIAD

Southampton Eastleigh

Sun 8/11

09:20-15:35

1 stop11h 15m

£430

SouthamptonWashington, D.C.

SOU - IAD

SOUIAD

Southampton Eastleigh

Mon 23/11

09:20-19:55

2 stops15h 35m

£450

Flights are sorted by cheapest return flights first.

Deals found on 11/6

Showing 1-10 of 11 resultsSorted by cheapest first
1
2

Best time to book a flight from Portsmouth to Dulles Intl

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

What is the cheapest time of day to fly from P0R to IAD?

Find hourly flight availability from Portsmouth to Dulles Intl. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated 16 June 2026.

When flying from Portsmouth to Washington, D.C. Dulles Intl Airport, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

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

Explore weekly flight availability from Portsmouth to Dulles Intl. 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 16 June 2026.

The most flights from P0R to IAD are scheduled on a Monday (28 on average). You will have fewer flight options on Wednesday, which is when the least amount of flights are scheduled (24 on average).

Reviews of airlines servicing Dulles Intl

Get insights into the airlines that provide service to Dulles Intl. 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 Dulles Intl. Reviews last updated 16 June 2026.
Get a feel of what it's like to fly with Aer Lingus from Portsmouth to Washington, D.C. Dulles Intl Airport by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Aer Lingus
7.3
Good
1,604 reviews
Check prices

Overall

7.3

Food

6.7

Comfort

7.2

Crew

8.1

Entertainment

7.0

Boarding

7.4

Reviews

1 / 20
2.0
Mediocre

Anonymous,May 2026

DUB - EWR

Underpricer is a terrible organization that inserted itself as a “travel agent” simply by way of me booking on kayak. Never would I have willing assented to using underpricer. Further, we had a problem whereby two duplicate one-way flights from Dublin were inadvertently booked for me and my wife, stemming from a family emergency. My wife’s sister / my sister in law had a brain tumor and immediate surgery to remove it, which obviously impacted our previously planned travel arrangements. I tried to cancel the flight due to the extenuating circumstances. Underpricer said canceling was not possible, but a credit would be possible for the exact same flight - one way from Dublin - to be used in one year from the original flight date. I asked if it would be possible to make the credit a general credit to any participating AerLingus airport destination, which would allow more flexibility than having to go back to Ireland within a year. In order to pursue the credit, Underpricer requested documentary proof regarding my sister in laws brain tumor, which we gave them. Underpricer then asked us to document our relationship to the patient - so I gave them my marriage certificate to evidence my wife and her sister having the same last name. Underpricer asked for further proof, so we gave them copies of my passport, my wife’s passport, and my sister in laws passport. All of these hoops to jump through for Underpricer, with sporadic communication on their part throughout, only for them to say 3 days before the original booking that no credit was available - not even the one they originally offered. They said my only option was to pick a date within the next year to move the flight to - and of course to make that change, they charged me an additional $350 fee just to make that change. What a pathetic, fraudulent organization. Kayak should be embarrassed to be associated with Underpricer and should cease that relationship immediately. And for AerLingus, who only Underpricer could talk to regarding the booking (I was not permitted) to not understand our family’s situation and just stand by blanket policy that no credit is permitted, is equally disappointing.
Aer Lingus
7.3
Good
1,604 reviews
Aer Lingus
7.3
Good
1,604 reviews
Check prices

Overall

7.3

Food

6.7

Comfort

7.2

Crew

8.1

Entertainment

7.0

Boarding

7.4

Reviews

1 / 20
2.0
Mediocre

Anonymous,May 2026

DUB - EWR

Underpricer is a terrible organization that inserted itself as a “travel agent” simply by way of me booking on kayak. Never would I have willing assented to using underpricer. Further, we had a problem whereby two duplicate one-way flights from Dublin were inadvertently booked for me and my wife, stemming from a family emergency. My wife’s sister / my sister in law had a brain tumor and immediate surgery to remove it, which obviously impacted our previously planned travel arrangements. I tried to cancel the flight due to the extenuating circumstances. Underpricer said canceling was not possible, but a credit would be possible for the exact same flight - one way from Dublin - to be used in one year from the original flight date. I asked if it would be possible to make the credit a general credit to any participating AerLingus airport destination, which would allow more flexibility than having to go back to Ireland within a year. In order to pursue the credit, Underpricer requested documentary proof regarding my sister in laws brain tumor, which we gave them. Underpricer then asked us to document our relationship to the patient - so I gave them my marriage certificate to evidence my wife and her sister having the same last name. Underpricer asked for further proof, so we gave them copies of my passport, my wife’s passport, and my sister in laws passport. All of these hoops to jump through for Underpricer, with sporadic communication on their part throughout, only for them to say 3 days before the original booking that no credit was available - not even the one they originally offered. They said my only option was to pick a date within the next year to move the flight to - and of course to make that change, they charged me an additional $350 fee just to make that change. What a pathetic, fraudulent organization. Kayak should be embarrassed to be associated with Underpricer and should cease that relationship immediately. And for AerLingus, who only Underpricer could talk to regarding the booking (I was not permitted) to not understand our family’s situation and just stand by blanket policy that no credit is permitted, is equally disappointing.

Related info for your journey

Find useful and relevant information for your journey from Portsmouth to Dulles Intl. 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 Portsmouth to Washington, D.C. Dulles Intl Airport?

    British Airways can get you from Portsmouth to Washington, D.C. Dulles Intl Airport in just under 14h 55m. Your travel time can differ by up to . Airlines will cover a distance of 3639 mi.

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

    Looking for the most reliable airlines to get you to your destination on time? Our data shows these are most likely to get you from Portsmouth to Washington, D.C. Dulles Intl Airport on time: Air Canada (87%), Austrian Airlines (87%), Copa Airlines (87%).

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

    The cheapest flight price from Portsmouth to Washington, D.C. Dulles Intl Airport is £436. On average you can expect to pay £994. The most popular route, (Southampton Eastleigh - Washington, D.C. Dulles Intl), can usually be booked for £508.

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

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

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

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

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

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

Book flights to Washington, D.C. Dulles Intl Airport if you plan to visit one of these locations
Silver Spring
Hanover
Oxon Hill
Gaithersburg
Woodbridge
Alexandria
Sterling

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Alternative routes for Portsmouth to Dulles Intl

See prices for flight routes from nearby airports that may be better suited for you.
Heathrow to Dulles Intl flights
Heathrow to Baltimore flights
Heathrow to Reagan-National flights
Gatwick to Dulles Intl flights
London City to Dulles Intl flights
Stansted to Dulles Intl flights
Gatwick to Baltimore flights
Gatwick to Reagan-National flights
Luton to Dulles Intl flights
Manchester to Dulles Intl flights
Manchester to Baltimore flights
Birmingham to Dulles Intl flights
Edinburgh to Dulles Intl flights
Luton to Baltimore flights
Birmingham to Reagan-National flights
Manchester to Reagan-National flights
Birmingham to Baltimore flights
London City to Baltimore flights
Edinburgh to Baltimore flights
Edinburgh to Reagan-National flights
Stansted to Baltimore flights
Leeds to Dulles Intl flights
Newcastle upon Tyne to Dulles Intl flights
Newcastle upon Tyne to Baltimore flights
Leeds to Baltimore flights
London City to Reagan-National flights
Southampton to Dulles Intl flights
Southampton to Baltimore flights
Newcastle upon Tyne to Reagan-National flights
Bristol to Dulles Intl flights
Bristol to Baltimore flights
Norwich to Baltimore flights
Leeds to Reagan-National flights
Norwich to Dulles Intl flights
Norwich to Reagan-National flights
Grimsby to Baltimore flights
Grimsby to Reagan-National flights
Grimsby to Dulles Intl flights
Bristol to Reagan-National flights
Exeter to Dulles Intl flights
Liverpool to Baltimore flights
Southampton to Reagan-National flights
Newquay to Baltimore flights
Southend to Dulles Intl flights
Doncaster to Dulles Intl flights
Doncaster to Baltimore flights
East Midlands to Baltimore flights

Top 10 airlines flying from Portsmouth to Dulles Intl

Discover the top 10 airlines that operate flights from Portsmouth to Dulles Intl. 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 16 June 2026.
AirlineCheapestAverageFlexibilityOn-time
IcelandairCheapest£328Average£435FlexibilityNo cancel feeOn-time76%
Search Icelandair flights
TAP AIR PORTUGALCheapest£341Average£405FlexibilityNo cancel feeOn-timeN/A
Search TAP AIR PORTUGAL flights
Aer LingusCheapest£363Average£582FlexibilityNo cancel feeOn-timeN/A
Search Aer Lingus flights
LufthansaCheapest£402Average£577FlexibilityNo cancel feeOn-time76%
Search Lufthansa flights
Virgin AtlanticCheapest£405Average£550FlexibilityNo cancel feeOn-time72%
Search Virgin Atlantic flights
Scandinavian AirlinesCheapest£409Average£595FlexibilityNo cancel feeOn-time77%
Search Scandinavian Airlines flights
British AirwaysCheapest£410Average£568FlexibilityNo cancel feeOn-time70%
Search British Airways flights
Austrian AirlinesCheapest£416Average£561FlexibilityNo cancel feeOn-time78%
Search Austrian Airlines flights
FinnairCheapest£417Average£623FlexibilityNo cancel feeOn-time76%
Search Finnair flights
United AirlinesCheapest£421Average£600FlexibilityNo cancel feeOn-time69%
Search United Airlines flights

Fly with Cheapflights

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How does Cheapflights help users find flights from Portsmouth to Dulles Intl?

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

Yes! Cheapflights helps users easily find flights from Portsmouth to Dulles Intl with no change fees.

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