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$269+ Cheap flights from Dulles Intl (IAD) to Porto (OPO)

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 4/16. Fares are subject to change and may not be available on all flights or dates of travel.
IAD — OPO
Apr 9 — Apr 161
Thu 4/9
Thu 4/16
1 adult, Economy
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Cheap flight deals from Dulles Intl to Porto

Cheapest flights from Dulles Intl to Porto
Explore the most affordable flight options available from Dulles Intl to Porto. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 10, 2026.

This Kiwi.com deal was found by Cheapflights users on 3/6. 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.
Thu 4/1610:35 pm
IAD
-
OPO
1 stop11h 25m
TAP AIR PORTUGAL
Thu 4/239:00 am
OPO
-
IAD
1 stop11h 10m
TAP AIR PORTUGAL
Deal found 3/6$555
This oojo deal was found by Cheapflights users on 3/9. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 4/265:40 pm
IAD
-
OPO
1 stop11h 20m
TAP AIR PORTUGAL
Thu 5/711:00 am
OPO
-
IAD
1 stop14h 35m
TAP AIR PORTUGAL
Deal found 3/9$558
This KLM deal was found by Cheapflights users on 3/5. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/116:15 pm
IAD
-
OPO
1 stop16h 10m
KLM
Tue 11/311:15 am
OPO
-
IAD
1 stop33h 30m
KLM
Deal found 3/5$563
This Gotogate deal was found by Cheapflights users on 3/9. 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/2010:35 pm
IAD
-
OPO
1 stop28h 25m
TAP AIR PORTUGAL
Wed 5/611:00 am
OPO
-
IAD
1 stop14h 35m
TAP AIR PORTUGAL
Deal found 3/9$565
This FlightHub deal was found by Cheapflights users on 3/6. 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.
Sat 4/258:20 pm
IAD
-
OPO
1 stop33h 50m
Scandinavian Airlines
Thu 5/711:50 am
OPO
-
IAD
1 stop34h 10m
Scandinavian Airlines
Deal found 3/6$571
This FlightHub deal was found by Cheapflights users on 3/7. 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 10/1110:35 pm
IAD
-
OPO
1 stop13h 25m
TAP AIR PORTUGAL
Thu 11/57:00 am
OPO
-
IAD
1 stop13h 15m
TAP AIR PORTUGAL
Deal found 3/7$573
This TAP AIR PORTUGAL deal was found by Cheapflights users on 3/5. 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 TAP AIR PORTUGAL is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/1510:35 pm
IAD
-
OPO
1 stop13h 25m
TAP AIR PORTUGAL
Tue 8/2511:00 am
OPO
-
IAD
1 stop14h 35m
TAP AIR PORTUGAL
Deal found 3/5$575
This FlightHub deal was found by Cheapflights users on 3/10. 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.
Tue 3/319:45 pm
IAD
-
OPO
1 stop20h 45m
Turkish Airlines
Wed 4/154:40 pm
OPO
-
IAD
1 stop32h 10m
Turkish Airlines
Deal found 3/10$578
This oojo deal was found by Cheapflights users on 3/6. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/110:35 pm
IAD
-
OPO
1 stop15h 25m
TAP AIR PORTUGAL
Mon 8/316:00 pm
OPO
-
IAD
1 stop26h 10m
TAP AIR PORTUGAL
Deal found 3/6$579
This United Airlines deal was found by Cheapflights users on 3/5. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/1312:58 pm
IAD
-
OPO
1 stop13h 02m
United Airlines
Fri 11/66:00 am
OPO
-
IAD
1 stop14h 50m
United Airlines
Deal found 3/5$580

Find flight deals from Dulles Intl to Porto

Discover tips and strategies to find the most affordable flight options for your journey from Dulles Intl (IAD) to Porto (OPO). 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 March 10, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$555
(Kiwi.com)

One-way from

$269
(Kiwi.com)

Popular in

December

Cheapest in

October

Average price

$724
Provider with most accurate pricing for Washington, D.C. Dulles Intl-Porto flight deals.
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Provider most trusted by Cheapflights users for Washington, D.C. Dulles Intl-Porto flights.
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From Washington, D.C. Dulles Intl to Porto
Search Deals
One-way flight from Washington, D.C. Dulles Intl to Porto
Search Deals
High demand for flights, 5% potential price rise
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($17 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in March 2026
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Cheapflights Fare Finder

 
Customize your flight search to find flights from Dulles Intl to Porto 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 March 10, 2026.
Use the filters below to find and compare flights from Washington, D.C. Dulles Intl Airport to Porto that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Wed 4/15

1:20 pm-3:40 pm

1 stop21h 20m

Porto

Wed 5/6

10:45 am-11:35 am

1 stop29h 50m

$603
Quickest round-trip

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Sun 4/19

10:35 pm-7:00 pm

1 stop15h 25m

Porto

Thu 4/23

9:00 am-8:35 pm

1 stop16h 35m

$645

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Sun 4/26

6:15 pm-3:25 pm

1 stop16h 10m

Porto

Thu 5/7

5:00 am-4:31 pm

2 stops16h 31m

$652

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Wed 5/6

6:15 pm-3:25 pm

1 stop16h 10m

Porto

Tue 5/12

5:00 am-6:53 pm

2 stops18h 53m

$682

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Sat 4/25

6:15 pm-3:25 pm

1 stop16h 10m

Porto

Thu 5/7

5:00 am-4:31 pm

2 stops16h 31m

$702

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Wed 4/15

6:10 pm-6:20 pm

1 stop19h 10m

Porto

Wed 5/6

5:00 am-4:15 pm

2 stops16h 15m

$709

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Wed 4/15

6:10 pm-6:20 pm

1 stop19h 10m

Porto

Sat 5/2

5:55 am-7:56 pm

2 stops19h 01m

$715

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Tue 3/31

9:45 pm-10:05 pm

1 stop19h 20m

Porto

Wed 4/15

5:00 am-6:19 pm

2 stops18h 19m

$789

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Sun 5/17

9:45 pm-10:00 pm

1 stop19h 15m

Porto

Mon 5/25

4:20 pm-3:35 pm

1 stop28h 15m

$850

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Sat 7/18

5:42 pm-9:45 am

1 stop11h 03m

Porto

Sat 7/25

10:15 am-7:26 am

2 stops26h 11m

$891

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/9

Showing 1-10 of 21 resultsSorted by cheapest first
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3

Compare providers for flights from Dulles Intl to Porto

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 Dulles Intl to Porto in March.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
AranGrantPrice Accuracy2 starsTrust Score*2 stars
OvagoPrice Accuracy2 starsTrust Score*3 stars
GotogatePrice Accuracy2 starsTrust Score*3 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars

*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 Washington, D.C. Dulles Intl Airport-Porto flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Washington, D.C. Dulles Intl Airport-Porto flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Washington, D.C. Dulles Intl Airport-Porto flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Washington, D.C. Dulles Intl Airport-Porto flights, Cheapflights users trust FlightHub the most. FlightHub 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 Washington, D.C. Dulles Intl Airport-Porto 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 Dulles Intl to Porto

Have a flexible travel schedule? Discover the best time to fly to Porto 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 Porto

How far ahead should I book a flight from Washington, D.C. Dulles Intl Airport to Porto?

Use this chart to determine the optimal time to book a round-trip flight from Dulles Intl to Porto. Price data was last updated on March 6, 2026.

To ensure you get the cheapest price possible for a flight from Washington, D.C. Dulles Intl Airport to Porto, you should look to book at least 78 days in advance of your intended travel date. The price of your flight may increase if you delay and leave booking until a week or so before departure.

What is the cheapest month to book a flight from Washington, D.C. Dulles Intl Airport to Porto?

Currently, December is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to Porto (average of $357). Flying from Washington, D.C. Dulles Intl Airport to Porto in June is currently the most expensive (average of $686). 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.

How much does it cost to fly round-trip from Washington, D.C. Dulles Intl Airport to Porto?

Reviews of airlines servicing Porto

Get insights into the airlines that provide service to Porto. 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 Porto. Reviews last updated March 10, 2026.
Get a feel of what it's like to fly with Delta,United Airlines, andTAP AIR PORTUGAL from Washington, D.C. Dulles Intl Airport to Porto by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Delta
7.9
Good
8,277 reviews

Crew

8.5

Overall

7.9

Entertainment

7.8

Boarding

8.1

Food

7.2

Comfort

7.9

Reviews

1 / 20
6.0
Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.
Delta
7.9
Good
8,277 reviews
Delta
7.9
Good
8,277 reviews

Crew

8.5

Overall

7.9

Entertainment

7.8

Boarding

8.1

Food

7.2

Comfort

7.9

Reviews

1 / 20
6.0
Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.
United Airlines
7.4
Good
9,413 reviews
Delta
7.9
Good
8,277 reviews

Crew

8.5

Overall

7.9

Entertainment

7.8

Boarding

8.1

Food

7.2

Comfort

7.9

Reviews

1 / 20
6.0
Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.
TAP AIR PORTUGAL
7.1
Good
2,162 reviews
Delta
7.9
Good
8,277 reviews

Crew

8.5

Overall

7.9

Entertainment

7.8

Boarding

8.1

Food

7.2

Comfort

7.9

Reviews

1 / 20
6.0
Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.
Iberia
7.0
Good
3,133 reviews
Delta
7.9
Good
8,277 reviews

Crew

8.5

Overall

7.9

Entertainment

7.8

Boarding

8.1

Food

7.2

Comfort

7.9

Reviews

1 / 20
6.0
Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.
Lufthansa
6.8
Okay
7,841 reviews
Delta
7.9
Good
8,277 reviews

Crew

8.5

Overall

7.9

Entertainment

7.8

Boarding

8.1

Food

7.2

Comfort

7.9

Reviews

1 / 20
6.0
Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.

Related info for your journey

Find useful and relevant information for your journey from Dulles Intl to Porto. 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 into for flights to Porto from Washington, D.C. Dulles Intl?

    Located just 6.8 mi from the city center, Porto is the airport most travelers will use when flying to Porto from Washington, D.C. Dulles Intl. Booking flights from Washington, D.C. Dulles Intl to Porto (OPO) should be relatively easy as there are 0 daily inbound flights from Washington, D.C. Dulles Intl from 8 different airlines.

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

    Departing from Washington, D.C. Dulles Intl Airport to Porto will take you 15h 25m. The distance from Washington, D.C. Dulles Intl Airport to Porto is about 3537 mi. This flight may include one or multiple stops.

  • What are the cheapest airlines flying from Washington, D.C. Dulles Intl Airport to Porto round-trip?

    Currently priced at $444, SWISS will fly you from Washington, D.C. Dulles Intl Airport to Porto and back. In addition to SWISS, many other airlines offer competitively priced options for your trip. Search Cheapflights for deals from KLM and TAP AIR PORTUGAL - these airlines can fly you to your destination from $477 and $490, respectively. These flights start at 38% lower than the current average price 3 months from now.

  • What are the cheapest airlines to fly from Washington, D.C. Dulles Intl Airport to Porto one-way?

    $251 is the cheapest one-way deal found within the past few days, from TAP AIR PORTUGAL. You may also be able to find cheap deals on KLM and United Airlines, with prices starting from $356 and $483, respectively.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Dulles Intl to Porto 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 Porto?

    Currently, December is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to Porto (average of $357). Flying from Washington, D.C. Dulles Intl Airport to Porto in June is currently the most expensive (average of $686). 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.

See more FAQs

Traveling to a place near Porto?

Book flights to Porto if you plan to visit one of these locations
Vila Nova de Gaia
Aveiro
Arcos de Valdevez
Coimbra

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Alternative routes for Dulles Intl to Porto

See prices for flight routes from nearby airports that may be better suited for you.
Dulles Intl to Lisbon flights
Baltimore to Lisbon flights
Reagan-National to Lisbon flights
Dulles Intl to Funchal flights
Baltimore to Lajes flights

Top 8 airlines flying from Dulles Intl to Porto

Discover the top 8 airlines that operate flights from Dulles Intl to Porto. 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 March 10, 2026.
AirlineCheapestAverageFlexibilityOn-time
SWISSCheapest$444Average$681FlexibilityNo cancel feeOn-time79%
KLMCheapest$477Average$745FlexibilityNo cancel feeOn-time75%
TAP AIR PORTUGALCheapest$490Average$747FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$494Average$823FlexibilityNo cancel feeOn-time69%
IberiaCheapest$515Average$672FlexibilityNo cancel feeOn-time77%
DeltaCheapest$533Average$1,025FlexibilityNo cancel feeOn-timeN/A
LufthansaCheapest$564Average$709FlexibilityNo cancel feeOn-time76%
American AirlinesCheapest$573Average$639FlexibilityNo cancel feeOn-time71%

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