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Dulles Intl

$338+ Cheap flights from Porto (OPO) to Dulles Intl (IAD)

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 4/27. Fares are subject to change and may not be available on all flights or dates of travel.
OPO — IAD
Dec 31 — Jan 71
Wed 12/31
Wed 1/7
1 adult, Economy
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Find flight deals from Porto to Dulles Intl

Cheapest flights from Porto to Dulles Intl
Explore the most affordable flight options available from Porto to Dulles Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on December 1, 2025.

This Expedia deal was found by Cheapflights users on 11/30. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/218:05 pmOPO - IAD
2 stops32h 59mMultiple Airlines
Sun 12/281:40 pmIAD - OPO
2 stops21h 20mMultiple Airlines
Deal found 11/30$672
This United Airlines deal was found by Cheapflights users on 12/1. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/296:00 amOPO - IAD
2 stops30h 30mUnited Airlines
Mon 1/58:15 amIAD - OPO
2 stops22h 25mUnited Airlines
Deal found 12/1$756
This Ovago deal was found by Cheapflights users on 11/30. 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 Ovago is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/246:00 amOPO - IAD
1 stop13h 35mMultiple Airlines
Sat 1/310:05 pmIAD - OPO
1 stop18h 55mMultiple Airlines
Deal found 11/30$818
This FlightHub deal was found by Cheapflights users on 12/1. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/288:00 pmOPO - IAD
1 stop24h 15mTAP AIR PORTUGAL
Sun 1/410:30 pmIAD - OPO
1 stop18h 30mTAP AIR PORTUGAL
Deal found 12/1$878
This Air France deal was found by Cheapflights users on 12/1. 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 Air France is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/296:30 amOPO - IAD
1 stop14h 35mMultiple Airlines
Mon 1/56:50 pmIAD - OPO
1 stop10h 40mMultiple Airlines
Deal found 12/1$1,005
This lastminute.com deal was found by Cheapflights users on 12/1. 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 lastminute.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/295:30 pmOPO - IAD
1 stop31h 25mBritish Airways
Mon 1/59:45 pmIAD - OPO
1 stop14h 50mBritish Airways
Deal found 12/1$1,044
This Sembo deal was found by Cheapflights users on 12/1. 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 Sembo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/298:30 amOPO - IAD
1 stop11h 45mTAP AIR PORTUGAL
Mon 1/55:10 pmIAD - OPO
2 stops16h 50mTAP AIR PORTUGAL
Deal found 12/1$1,055

Cheap flight deals from Porto to Dulles Intl

Discover tips and strategies to find the most affordable flight options for your journey from Porto (OPO) to Dulles Intl (IAD). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated December 1, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$502
(United Airlines)

One-way from

$338
(Cheapflightsfares)

Popular in

July

Cheapest in

May

Average price

$620
Provider with most accurate pricing for Porto-Washington, D.C. Dulles Intl flight deals.
Search Deals
Provider most trusted by Cheapflights users for Porto-Washington, D.C. Dulles Intl flights.
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From Porto to Washington, D.C. Dulles Intl
Search Deals
One-way flight from Porto to Washington, D.C. Dulles Intl
Search Deals
Highest demand for flights based on searches. 9% potential increase in price ($66 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($12 potential savings vs. average RT price).
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Average for round-trip flights in December 2025
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Cheapflights Fare Finder

 
Customize your flight search to find flights from Porto 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 2,558,603 searches. Data last updated December 1, 2025.
Use the filters below to find and compare flights from Porto to Washington, D.C. Dulles Intl Airport that are best for you.

Fly from

Porto

Fly to

Dulles Intl

Route

Depart

Return

Price

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Thu 3/5

6:00 am-2:35 pm

1 stop13h 35m

Washington, D.C. Dulles Intl

Mon 3/9

5:35 pm-9:30 am

1 stop11h 55m

$502

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Thu 1/15

6:00 am-8:26 pm

2 stops43h 26m

Washington, D.C. Dulles Intl

Wed 1/28

9:45 am-11:15 am

2 stops20h 30m

$503

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Thu 1/15

6:00 am-2:35 pm

1 stop13h 35m

Washington, D.C. Dulles Intl

Wed 1/28

8:20 am-3:25 pm

2 stops26h 05m

$506

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Thu 1/15

6:00 am-3:46 pm

2 stops38h 46m

Washington, D.C. Dulles Intl

Wed 1/28

6:00 pm-11:40 am

1 stop12h 40m

$509

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Wed 1/14

12:10 pm-3:30 pm

1 stop32h 20m

Washington, D.C. Dulles Intl

Wed 1/21

5:45 pm-11:15 am

1 stop12h 30m

$511

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Thu 1/15

6:35 am-4:05 pm

1 stop14h 30m

Washington, D.C. Dulles Intl

Wed 1/28

12:23 pm-10:30 am

2 stops17h 07m

$511

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Thu 3/5

8:20 am-4:30 pm

1 stop13h 10m

Washington, D.C. Dulles Intl

Mon 3/9

7:20 pm-7:40 am

2 stops32h 20m

$512

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Thu 3/5

6:00 am-3:46 pm

2 stops38h 46m

Washington, D.C. Dulles Intl

Mon 3/9

9:55 am-2:55 pm

2 stops25h 00m

$512

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Mon 4/27

8:20 am-3:30 pm

1 stop12h 10m

$338

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Sun 5/3

8:20 am-3:30 pm

1 stop12h 10m

$338

Flights are sorted by cheapest round-trip flights first.

Deals found on 11/29

Showing 1-10 of 19 results
1
2

Compare providers for flights from Porto to Dulles Intl

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Porto to Dulles Intl in December.
ProviderPrice AccuracyTrust Score*
eDreamsPrice Accuracy3 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*1 star

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Porto-Washington, D.C. Dulles Intl Airport flights, users find the pricing of eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on Porto-Washington, D.C. Dulles Intl Airport flight deals on Cheapflights vs. eDreams >95% of the time. Price accuracy is based on data collected from Porto-Washington, D.C. Dulles Intl Airport flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Porto-Washington, D.C. Dulles Intl Airport flights, Cheapflights users trust eDreams the most. eDreams has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Porto-Washington, D.C. Dulles Intl Airport flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from Porto to Dulles Intl

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

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

Find hourly flight availability from Porto 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 December 1, 2025.

It’s optimal to fly from Porto to Washington, D.C. Dulles Intl Airport in the afternoon. By choosing this option you can save up to 46% on the cost of your flight, compared to a flight at noon.

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 December 1, 2025.
Get a feel of what it's like to fly with TAP AIR PORTUGAL from Porto 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.
TAP AIR PORTUGAL
7.1
Good
2,079 reviews

Overall

7.1

Food

6.2

Comfort

7.1

Crew

7.8

Entertainment

6.3

Boarding

7.0

Reviews

1 / 20
8.0
Excellent

Michael,Dec 2025

FNC - LIS

Long wait standing after checking in at the gate Limited juice selection.
TAP AIR PORTUGAL
7.1
Good
2,079 reviews
TAP AIR PORTUGAL
7.1
Good
2,079 reviews

Overall

7.1

Food

6.2

Comfort

7.1

Crew

7.8

Entertainment

6.3

Boarding

7.0

Reviews

1 / 20
8.0
Excellent

Michael,Dec 2025

FNC - LIS

Long wait standing after checking in at the gate Limited juice selection.

Related info for your journey

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

  • What airport do you fly from for flights from Porto to Washington, D.C. Dulles Intl?

    Porto (OPO), located 6.8 mi from the city center, is the airport you fly out of when you book flights from Porto to Washington, D.C. Dulles Intl. 1 airline have flights from Porto to Washington, D.C. Dulles Intl on a regular basis. Booking flights from Porto to Washington, D.C. Dulles Intl should not be difficult; the airport handles an average of 0 outbound flights to Washington, D.C. Dulles Intl per day.

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

    United Airlines and Air Canada can get you from Porto to Washington, D.C. Dulles Intl Airport in just under 13h 35m. Your travel time can differ by up to 29h 51m. Porto and Washington, D.C. Dulles Intl Airport are separated by a distance of 3537 mi. Both multi-stop and nonstop flights can be found to your destination and back.

  • What is the cheapest airline to fly from Porto to Washington, D.C. Dulles Intl Airport round-trip?

    TAP AIR PORTUGAL, at $480, was found to be the cheapest airline from Porto to Washington, D.C. Dulles Intl Airport..

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Porto 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

Traveling 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
Alexandria
Woodbridge
Tysons
Arlington
Owings Mills
Springfield
Hanover
Silver Spring
Fredericksburg
Fairfax
Linthicum Heights
Manassas
Laurel
Towson
National Harbor
Bowie
Largo
McLean
Clinton
Upper Marlboro

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Alternative routes for Porto to Dulles Intl

See prices for flight routes from nearby airports that may be better suited for you.
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Porto to Baltimore flights

Top airline flying from Porto to Dulles Intl

Discover the top airline that operate flights from Porto 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 2,558,603 searches. Data last updated December 1, 2025.
AirlineCheapestAverageFlexibilityOn-time
TAP AIR PORTUGALCheapest$480Average$808FlexibilityNo cancel feeOn-timeN/A

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