HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
Porto

$314+ 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 3/20. Fares are subject to change and may not be available on all flights or dates of travel.
IAD — OPO
Feb 25 — Mar 41
Wed 2/25
Wed 3/4
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Dulles Intl to Porto with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.

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 January 26, 2026.

This oojo deal was found by Cheapflights users on 1/24. 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.
Fri 3/2011:30 pm
IAD
-
OPO
1 stop15h 30m
TAP AIR PORTUGAL
Fri 3/276:00 pm
OPO
-
IAD
1 stop26h 15m
TAP AIR PORTUGAL
Deal found 1/24$371
This oojo deal was found by Cheapflights users on 1/26. 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.
Wed 2/1810:30 pm
IAD
-
OPO
1 stop15h 30m
TAP AIR PORTUGAL
Tue 2/2410:15 pm
OPO
-
IAD
1 stop27h 45m
TAP AIR PORTUGAL
Deal found 1/26$378
This Cheapflightsfares deal was found by Cheapflights users on 1/25. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 2/245:30 pm
IAD
-
OPO
1 stop14h 40m
TAP AIR PORTUGAL
Tue 3/36:55 am
OPO
-
IAD
1 stop12h 40m
TAP AIR PORTUGAL
Deal found 1/25$385
This FlightHub deal was found by Cheapflights users on 1/23. 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.
Wed 2/1810:30 pm
IAD
-
OPO
1 stop18h 30m
TAP AIR PORTUGAL
Thu 2/269:00 am
OPO
-
IAD
1 stop11h 15m
TAP AIR PORTUGAL
Deal found 1/23$388
This Kiwi.com deal was found by Cheapflights users on 1/23. 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.
Mon 2/165:30 pm
IAD
-
OPO
1 stop18h 30m
TAP AIR PORTUGAL
Mon 2/235:55 pm
OPO
-
IAD
1 stop25h 40m
TAP AIR PORTUGAL
Deal found 1/23$397
This Kiwi.com deal was found by Cheapflights users on 1/23. 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.
Sun 2/2210:30 pm
IAD
-
OPO
1 stop11h 50m
TAP AIR PORTUGAL
Sun 3/18:00 pm
OPO
-
IAD
1 stop24h 15m
TAP AIR PORTUGAL
Deal found 1/23$399
This Kiwi.com deal was found by Cheapflights users on 1/23. 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.
Tue 2/175:30 pm
IAD
-
OPO
1 stop11h 40m
TAP AIR PORTUGAL
Mon 2/238:00 pm
OPO
-
IAD
1 stop23h 35m
TAP AIR PORTUGAL
Deal found 1/23$451
This Kiwi.com deal was found by Cheapflights users on 1/24. 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.
Sun 3/1511:30 pm
IAD
-
OPO
1 stop15h 30m
TAP AIR PORTUGAL
Tue 3/246:55 am
OPO
-
IAD
1 stop12h 40m
TAP AIR PORTUGAL
Deal found 1/24$453
This oojo deal was found by Cheapflights users on 1/26. 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.
Tue 4/75:05 pm
IAD
-
OPO
1 stop22h 20m
TAP AIR PORTUGAL
Wed 4/157:00 am
OPO
-
IAD
1 stop18h 35m
TAP AIR PORTUGAL
Deal found 1/26$455
This oojo deal was found by Cheapflights users on 1/26. 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 2/110:30 pm
IAD
-
OPO
1 stop15h 30m
TAP AIR PORTUGAL
Mon 2/96:55 am
OPO
-
IAD
1 stop13h 20m
TAP AIR PORTUGAL
Deal found 1/26$460
This Cheapflightsfares deal was found by Cheapflights users on 1/25. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/810:35 pm
IAD
-
OPO
1 stop13h 25m
TAP AIR PORTUGAL
Wed 4/157:00 am
OPO
-
IAD
1 stop18h 35m
TAP AIR PORTUGAL
Deal found 1/25$466
This Mytrip deal was found by Cheapflights users on 1/23. 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.
Tue 3/106:30 pm
IAD
-
OPO
2 stops20h 55m
Multiple Airlines
Tue 3/175:35 pm
OPO
-
IAD
2 stops32h 25m
Multiple Airlines
Deal found 1/23$471

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 January 26, 2026.

Most accurate provider

Gotogate
3 stars

Most trusted provider

Gotogate
3 stars

Round-trip from

$371
(oojo)

One-way from

$314
(Kiwi.com)

Popular in

May

Cheapest in

October

Average price

$686
Provider with most accurate pricing for Washington, D.C. Dulles Intl-Porto flight deals.
Search Deals
Provider most trusted by Cheapflights users for Washington, D.C. Dulles Intl-Porto flights.
Search Deals
From Washington, D.C. Dulles Intl to Porto
Search Deals
One-way flight from Washington, D.C. Dulles Intl to Porto
Search Deals
Highest demand for flights based on searches. 10% potential increase in price ($80 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($14 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in January 2026
Search Deals

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 January 26, 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

Dulles Intl

Fly to

Porto

Route

Depart

Return

Price

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Tue 2/24

5:30 pm-1:10 pm

1 stop14h 40m

Porto

Tue 3/3

6:55 am-2:35 pm

1 stop12h 40m

$385

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Thu 1/29

5:30 pm-6:00 pm

1 stop19h 30m

Porto

Thu 2/12

7:00 am-3:15 pm

1 stop13h 15m

$480

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Fri 4/17

10:35 pm-7:00 pm

1 stop15h 25m

Porto

Wed 4/22

10:25 pm-3:05 pm

1 stop21h 40m

$528

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Wed 4/1

10:35 pm-11:10 pm

1 stop19h 35m

Porto

Wed 4/15

11:00 am-8:35 pm

1 stop14h 35m

$570

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Mon 3/16

1:19 pm-10:30 am

2 stops17h 11m

Porto

Tue 3/24

5:00 am-5:05 pm

1 stop16h 05m

$578

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Mon 3/16

1:19 pm-10:30 am

2 stops17h 11m

Porto

Mon 3/23

11:15 am-5:05 pm

1 stop33h 50m

$578

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Tue 2/24

12:38 pm-10:30 am

2 stops16h 52m

Porto

Tue 3/3

5:00 am-4:05 pm

1 stop16h 05m

$579

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Wed 3/11

7:05 pm-7:20 pm

1 stop20h 15m

Porto

Mon 3/23

4:10 pm-5:05 pm

1 stop28h 55m

$580

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Wed 3/11

7:05 pm-10:25 pm

1 stop23h 20m

Porto

Fri 3/20

5:00 am-5:05 pm

1 stop16h 05m

$580

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Wed 3/11

7:05 pm-3:25 pm

1 stop16h 20m

Porto

Tue 3/24

11:15 am-5:05 pm

1 stop33h 50m

$580

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/26

Showing 1-10 of 18 results
1
2

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 January.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy2 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*1 star
AranGrantPrice Accuracy2 starsTrust Score*3 stars
OvagoPrice Accuracy2 starsTrust Score*2 stars
GotogatePrice Accuracy3 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 Gotogate to be most consistent on Cheapflights vs. Gotogate Users can find the same prices on Washington, D.C. Dulles Intl Airport-Porto flight deals on Cheapflights vs. Gotogate >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 Gotogate the most. Gotogate 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 January 23, 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 40 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 $687). 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.

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 January 26, 2026.
Get a feel of what it's like to fly with Delta, United Airlines, and TAP 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
8,113 reviews

Crew

8.5

Comfort

7.9

Food

7.2

Boarding

8.1

Entertainment

7.8

Overall

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
8,113 reviews
Delta
7.9
Good
8,113 reviews

Crew

8.5

Comfort

7.9

Food

7.2

Boarding

8.1

Entertainment

7.8

Overall

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
9,199 reviews
Delta
7.9
Good
8,113 reviews

Crew

8.5

Comfort

7.9

Food

7.2

Boarding

8.1

Entertainment

7.8

Overall

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
2,130 reviews
Delta
7.9
Good
8,113 reviews

Crew

8.5

Comfort

7.9

Food

7.2

Boarding

8.1

Entertainment

7.8

Overall

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
3,098 reviews
Delta
7.9
Good
8,113 reviews

Crew

8.5

Comfort

7.9

Food

7.2

Boarding

8.1

Entertainment

7.8

Overall

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
7,747 reviews
Delta
7.9
Good
8,113 reviews

Crew

8.5

Comfort

7.9

Food

7.2

Boarding

8.1

Entertainment

7.8

Overall

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 7 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 14h 40m. 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 $439, Delta will fly you from Washington, D.C. Dulles Intl Airport to Porto and back. In addition to Delta, many other airlines offer competitively priced options for your trip. Search Cheapflights for deals from SWISS and KLM - these airlines can fly you to your destination from $444 and $477, 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 $384 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 $687). 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

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Top 7 airlines flying from Dulles Intl to Porto

Discover the top 7 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 January 26, 2026.
AirlineCheapestAverageFlexibilityOn-time
DeltaCheapest$439Average$826FlexibilityNo cancel feeOn-timeN/A
SWISSCheapest$444Average$681FlexibilityNo cancel feeOn-time79%
KLMCheapest$477Average$731FlexibilityNo cancel feeOn-time75%
United AirlinesCheapest$494Average$783FlexibilityNo cancel feeOn-time69%
TAP AIR PORTUGALCheapest$497Average$768FlexibilityNo cancel feeOn-timeN/A
IberiaCheapest$515Average$672FlexibilityNo cancel feeOn-time77%
LufthansaCheapest$602Average$691FlexibilityNo cancel feeOn-time76%

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.