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Cheap flights from Portsmouth to Washington, D.C. Dulles Intl Airport from £440

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 23/11. Fares are subject to change and may not be available on all flights or dates of travel.
LHR — IAD
3 Sep — 10 Sep1
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 4 August 2026.

Mon 14/917:20
SOU
-
IAD
2 stops30h 30m
Aer Lingus
Mon 21/917:00
IAD
-
SOU
2 stops18h 50m
Aer Lingus
Deal found 31/7£543
Thu 29/1009:20
SOU
-
IAD
2 stops36h 00m
Aer Lingus
Thu 5/1117:50
IAD
-
SOU
2 stops20h 40m
Aer Lingus
Deal found 31/7£555
Wed 19/809:20
SOU
-
IAD
1 stop11h 25m
Aer Lingus
Wed 30/917:15
IAD
-
SOU
1 stop10h 25m
Aer Lingus
Deal found 1/8£619
Wed 19/809:20
SOU
-
IAD
1 stop11h 25m
Aer Lingus
Wed 4/1117:50
IAD
-
SOU
2 stops20h 40m
Aer Lingus
Deal found 1/8£635

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 4 August 2026.

Round-trip from

£543

One-way from

£440

Popular in

June

Cheapest in

February

Average price

£553
Aer Lingus
  • Aer Lingus
  • 14/9-21/9
  • 4 total stops
  • 49h 20m total
  • Portsmouth to Washington, D.C.
Search Deals
23/11
  • 23/11
  • 2 total stops
  • 24h 40m total
  • Portsmouth to Washington, D.C.
Search Deals
Highest demand for flights based on searches. 9% potential increase in price (£38 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 August 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 4 August 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
Fastest return journey

SouthamptonWashington, D.C.

SOU - IAD

SOUIAD

Southampton Eastleigh

Thu 29/10

08:40-16:45

1 stop12h 05m

Washington, D.C. Dulles Intl

Thu 5/11

17:45-08:10

1 stop9h 25m

£652

SouthamptonWashington, D.C.

SOU - IAD

SOUIAD

Southampton Eastleigh

Mon 14/9

09:05-15:35

1 stop11h 30m

Washington, D.C. Dulles Intl

Mon 21/9

18:10-16:50

1 stop17h 40m

£653

SouthamptonWashington, D.C.

SOU - IAD

SOUIAD

Southampton Eastleigh

Thu 29/10

08:40-16:45

1 stop12h 05m

Washington, D.C. Dulles Intl

Thu 5/11

17:45-08:10

1 stop9h 25m

£653

SouthamptonWashington, D.C.

SOU - IAD

SOUIAD

Southampton Eastleigh

Wed 19/8

09:15-15:35

1 stop11h 20m

Washington, D.C. Dulles Intl

Wed 30/9

18:26-16:50

2 stops17h 24m

£731

SouthamptonWashington, D.C.

SOU - IAD

SOUIAD

Southampton Eastleigh

Thu 20/8

09:15-20:55

2 stops16h 40m

Washington, D.C. Dulles Intl

Tue 3/11

17:45-08:10

1 stop9h 25m

£734

SouthamptonWashington, D.C.

SOU - IAD

SOUIAD

Southampton Eastleigh

Wed 19/8

09:15-18:33

2 stops14h 18m

Washington, D.C. Dulles Intl

Thu 5/11

12:30-08:10

2 stops14h 40m

£738

SouthamptonWashington, D.C.

SOU - IAD

SOUIAD

Southampton Eastleigh

Fri 9/10

20:00-15:45

1 stop24h 45m

Washington, D.C. Dulles Intl

Mon 12/10

20:55-19:30

1 stop17h 35m

£740

SouthamptonWashington, D.C.

SOU - IAD

SOUIAD

Southampton Eastleigh

Thu 8/10

09:20-15:45

1 stop11h 25m

Washington, D.C. Dulles Intl

Tue 13/10

21:05-19:30

1 stop17h 25m

£740
Cheapest one-way

SouthamptonWashington, D.C.

SOU - IAD

SOUIAD

Southampton Eastleigh

Mon 23/11

20:00-15:40

2 stops24h 40m

£440
Fastest single journey

SouthamptonWashington, D.C.

SOU - IAD

SOUIAD

Southampton Eastleigh

Mon 23/11

09:20-15:35

1 stop11h 15m

£451

Flights are sorted by cheapest return flights first.

Deals found on 30/7

Showing 1-10 of 13 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 4 August 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 4 August 2026.

The most flights from P0R to IAD are scheduled on a Friday (34 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 4 August 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
1,685 reviews
Check prices

Boarding

7.4

Entertainment

7.0

Comfort

7.2

Overall

7.3

Food

6.7

Crew

8.1

Reviews

1 / 20
10.0
Excellent

Griffith,Feb 2026

MAN - DUB

Great experience. Crew was friendly, food was better than what I have experienced with some other airlines and seat pitch was adequate. I would fly Aer Lingus again.
Aer Lingus
7.3
Good
1,685 reviews
Aer Lingus
7.3
Good
1,685 reviews
Check prices

Boarding

7.4

Entertainment

7.0

Comfort

7.2

Overall

7.3

Food

6.7

Crew

8.1

Reviews

1 / 20
10.0
Excellent

Griffith,Feb 2026

MAN - DUB

Great experience. Crew was friendly, food was better than what I have experienced with some other airlines and seat pitch was adequate. I would fly Aer Lingus again.

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?

    KLM, Virgin Atlantic, and Delta can get you from Portsmouth to Washington, D.C. Dulles Intl Airport in just under 11h 30m. Your travel time can differ by up to 35m. Airlines will cover a distance of 3639 mi. When browsing for deals, the options you’ll see will be for both direct flights and flights with stops.

  • 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 (83%), Austrian Airlines (83%), Copa Airlines (83%).

  • 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 £409. On average you can expect to pay £1,633. The most popular route, (Southampton Eastleigh - Washington, D.C. Dulles Intl), can usually be booked for £558.

  • 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
Gaithersburg
Oxon Hill
Hanover
Woodbridge
Springfield
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
Gatwick to Dulles Intl flights
Heathrow to Reagan-National flights
London City to Dulles Intl flights
Stansted to Dulles Intl flights
Luton to Dulles Intl flights
Gatwick to Baltimore flights
Gatwick to Reagan-National flights
Edinburgh to Dulles Intl flights
Manchester to Dulles Intl flights
Stansted to Baltimore flights
Edinburgh to Reagan-National flights
Manchester to Baltimore flights
Luton to Baltimore flights
London City to Baltimore flights
Edinburgh to Baltimore flights
Manchester to Reagan-National flights
Birmingham to Dulles Intl flights
Birmingham to Baltimore flights
London City to Reagan-National flights
Birmingham to Reagan-National flights
Southampton to Dulles Intl flights
Southampton to Baltimore flights
Bristol to Baltimore flights
Leeds to Dulles Intl flights
Southend to Dulles Intl flights
Newcastle upon Tyne to Baltimore flights
Leeds to Baltimore flights
Bristol to Dulles Intl flights
Newcastle upon Tyne to Reagan-National flights
Liverpool to Baltimore flights
Exeter to Dulles Intl flights
Bristol to Reagan-National flights
Norwich to Baltimore flights
Newcastle upon Tyne to Dulles Intl flights
Newquay to Baltimore flights
Norwich to Dulles Intl flights
Leeds to Reagan-National flights
Southampton to Reagan-National flights
Norwich to Reagan-National flights
Grimsby to Baltimore flights
Doncaster to Baltimore flights
Grimsby to Reagan-National flights
Doncaster to Dulles Intl flights
Grimsby to Dulles Intl 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 4 August 2026.
AirlineCheapestAverageFlexibilityOn-time
IcelandairCheapest£327Average£414FlexibilityNo cancel feeOn-time76%
Search Icelandair flights
Aer LingusCheapest£363Average£577FlexibilityNo cancel feeOn-timeN/A
Search Aer Lingus flights
TAP AIR PORTUGALCheapest£382Average£449FlexibilityNo cancel feeOn-timeN/A
Search TAP AIR PORTUGAL flights
Virgin AtlanticCheapest£397Average£542FlexibilityNo cancel feeOn-time72%
Search Virgin Atlantic flights
LufthansaCheapest£404Average£563FlexibilityNo cancel feeOn-time76%
Search Lufthansa flights
British AirwaysCheapest£405Average£558FlexibilityNo cancel feeOn-time70%
Search British Airways flights
Air FranceCheapest£407Average£647FlexibilityNo cancel feeOn-time77%
Search Air France flights
Scandinavian AirlinesCheapest£408Average£476FlexibilityNo cancel feeOn-time77%
Search Scandinavian Airlines flights
FinnairCheapest£417Average£600FlexibilityNo cancel feeOn-time76%
Search Finnair flights
Austrian AirlinesCheapest£418Average£569FlexibilityNo cancel feeOn-time78%
Search Austrian Airlines flights

Fly with Cheapflights

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

When you search for this flight from Portsmouth to Dulles Intl, Cheapflights searches on 900+ travel sites to save you time finding great flight deals online. Additionally, we offer filter features so you can choose a preferred cabin class or airline, see different price ranges, and much more so you can book the flight for you.

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

Cheapflights simply makes it quick and affordable to book flights from Portsmouth to Dulles Intl by bringing together all flight options from hundreds of airlines and agencies online — and put it in one place for you to choose from. Plus, Cheapflights is 100% free to use for all.

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.

Can Cheapflights notify me if prices for flights from Portsmouth to Dulles Intl become cheaper?

Of course! You can now track prices for flights from Portsmouth to Dulles Intl and get an alert from Cheapflights when they change. Have a valid email address ready and click the bell icon next to the flight deals above to set up your price alerts.

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