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$295+ 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 12/8. Fares are subject to change and may not be available on all flights or dates of travel.
IAD — OPO
Nov 27 — Dec 41
Thu 11/27
Thu 12/4
1 adult, Economy
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Cheapflights Tip: The best prices from Washington, D.C. Dulles Intl to Porto are usually found in February or October, booked 78 days in advance, depart on a Sunday or Saturday and return on a Monday

Find 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 October 28, 2025.

This Delta deal was found by Cheapflights users on 10/27. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/1112:36 pmIAD - OPO
2 stops16h 54mDelta
Tue 11/1811:15 amOPO - IAD
2 stops18h 01mDelta
Deal found 10/27$492
This United Airlines deal was found by Cheapflights users on 10/27. 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 11/185:25 pmIAD - OPO
1 stop11h 05mUnited Airlines
Tue 12/212:30 pmOPO - IAD
1 stop32h 20mUnited Airlines
Deal found 10/27$493
This KAYAK deal was found by Cheapflights users on 10/26. 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 KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 11/98:30 pmIAD - OPO
1 stop33h 45mSWISS
Mon 11/179:10 amOPO - IAD
2 stops36h 30mSWISS
Deal found 10/26$495
This Delta deal was found by Cheapflights users on 10/26. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/305:29 pmIAD - OPO
2 stops16h 56mDelta
Tue 1/136:05 amOPO - IAD
2 stops22h 01mDelta
Deal found 10/26$497
This Delta deal was found by Cheapflights users on 10/28. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/1912:11 pmIAD - OPO
2 stops17h 19mDelta
Tue 12/166:05 amOPO - IAD
2 stops22h 03mDelta
Deal found 10/28$498
This United Airlines deal was found by Cheapflights users on 10/26. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/2210:35 pmIAD - OPO
2 stops35h 40mUnited Airlines
Tue 12/166:00 amOPO - IAD
1 stop14h 50mUnited Airlines
Deal found 10/26$499
This FlightHub deal was found by Cheapflights users on 10/26. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/119:45 amIAD - OPO
2 stops20h 55mMultiple Airlines
Tue 11/181:45 pmOPO - IAD
1 stop35h 20mMultiple Airlines
Deal found 10/26$500
This Priceline deal was found by Cheapflights users on 10/27. 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/39:45 amIAD - OPO
2 stops22h 30mMultiple Airlines
Sun 12/76:15 amOPO - IAD
1 stop18h 50mMultiple Airlines
Deal found 10/27$502
This Delta deal was found by Cheapflights users on 10/26. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/106:50 pmIAD - OPO
1 stop10h 40mDelta
Mon 11/1711:25 amOPO - IAD
2 stops41h 51mDelta
Deal found 10/26$506
This Delta deal was found by Cheapflights users on 10/26. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 11/96:00 amIAD - OPO
2 stops47h 30mDelta
Mon 11/1711:25 amOPO - IAD
2 stops39h 07mDelta
Deal found 10/26$512

Cheap 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 October 28, 2025.

Most accurate provider

Gotogate
3 stars

Most trusted provider

Gotogate
3 stars

Round-trip from

$489
(FlightHub)

One-way from

$295
(Kiwi.com)

Popular in

December

Cheapest in

February

Average price

$573
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. 7% potential increase in price ($63 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 4% potential price decrease ($36 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in October 2025
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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 October 28, 2025.
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 11/18

6:00 am-10:30 am

2 stops23h 30m

Porto

Tue 12/2

6:05 am-7:19 pm

2 stops42h 14m

$492

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Tue 11/11

12:36 pm-10:30 am

2 stops16h 54m

Porto

Tue 11/18

11:15 am-12:16 am

2 stops18h 01m

$492

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Mon 11/17

7:49 pm-10:30 am

2 stops33h 41m

Porto

Tue 12/2

6:05 am-7:19 pm

2 stops42h 14m

$492

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Sun 11/16

5:59 pm-10:30 am

2 stops35h 31m

Porto

Tue 12/2

6:05 am-7:19 pm

2 stops42h 14m

$492

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Tue 12/30

5:29 pm-3:25 pm

2 stops16h 56m

Porto

Wed 1/14

6:00 am-7:09 pm

2 stops18h 09m

$497

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Wed 12/3

12:50 pm-11:40 am

2 stops17h 50m

Porto

Wed 12/10

6:00 am-8:26 pm

2 stops43h 26m

$499

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Mon 2/2

6:50 pm-10:30 am

1 stop10h 40m

Porto

Sun 2/8

5:00 am-4:05 pm

1 stop16h 05m

$502

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Wed 12/3

12:50 pm-11:40 am

2 stops17h 50m

Porto

Wed 12/17

6:00 am-9:14 pm

2 stops20h 14m

$503

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Sat 11/15

5:59 pm-10:30 am

2 stops35h 31m

Porto

Tue 12/2

11:25 am-4:35 pm

1 stop34h 10m

$506

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Wed 1/14

12:23 pm-10:30 am

2 stops17h 07m

Porto

Sat 2/28

6:00 am-4:05 pm

1 stop15h 05m

$507

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/27

Showing 1-10 of 23 results
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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 October.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy2 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*1 star
eDreamsPrice Accuracy3 starsTrust Score*3 stars
GotogatePrice Accuracy3 starsTrust Score*3 stars
AranGrantPrice Accuracy2 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 October 24, 2025.

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, February is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to Porto (average of $406). Flying from Washington, D.C. Dulles Intl Airport to Porto in May is currently the most expensive (average of $688). 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.

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

Find hourly flight availability from Dulles Intl to Porto. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated October 28, 2025.

It’s typically best to fly out from Washington, D.C. Dulles Intl Airport to Porto at noon. Doing so could potentially save you 42% on the flight price compared to flying in the evening, which is usually more expensive.

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 October 28, 2025.
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
7,995 reviews

Boarding

8.2

Comfort

7.9

Overall

7.9

Entertainment

7.9

Food

7.3

Crew

8.5

Reviews

1 / 20
8.0
Excellent

Matthew,Oct 2025

GSP - ATL

This is always a full flight since it is the connecting route to primary destinations through Atlanta. That said, the crew handles the full load well. Not much more to say, it is a short flight with no in-flight services due to the length.
Delta
7.9
Good
7,995 reviews
Delta
7.9
Good
7,995 reviews

Boarding

8.2

Comfort

7.9

Overall

7.9

Entertainment

7.9

Food

7.3

Crew

8.5

Reviews

1 / 20
8.0
Excellent

Matthew,Oct 2025

GSP - ATL

This is always a full flight since it is the connecting route to primary destinations through Atlanta. That said, the crew handles the full load well. Not much more to say, it is a short flight with no in-flight services due to the length.
United Airlines
7.4
Good
8,996 reviews
Delta
7.9
Good
7,995 reviews

Boarding

8.2

Comfort

7.9

Overall

7.9

Entertainment

7.9

Food

7.3

Crew

8.5

Reviews

1 / 20
8.0
Excellent

Matthew,Oct 2025

GSP - ATL

This is always a full flight since it is the connecting route to primary destinations through Atlanta. That said, the crew handles the full load well. Not much more to say, it is a short flight with no in-flight services due to the length.
TAP AIR PORTUGAL
7.1
Good
2,033 reviews
Delta
7.9
Good
7,995 reviews

Boarding

8.2

Comfort

7.9

Overall

7.9

Entertainment

7.9

Food

7.3

Crew

8.5

Reviews

1 / 20
8.0
Excellent

Matthew,Oct 2025

GSP - ATL

This is always a full flight since it is the connecting route to primary destinations through Atlanta. That said, the crew handles the full load well. Not much more to say, it is a short flight with no in-flight services due to the length.
Iberia
7.0
Good
3,001 reviews
Delta
7.9
Good
7,995 reviews

Boarding

8.2

Comfort

7.9

Overall

7.9

Entertainment

7.9

Food

7.3

Crew

8.5

Reviews

1 / 20
8.0
Excellent

Matthew,Oct 2025

GSP - ATL

This is always a full flight since it is the connecting route to primary destinations through Atlanta. That said, the crew handles the full load well. Not much more to say, it is a short flight with no in-flight services due to the length.
Lufthansa
6.8
Okay
7,532 reviews
Delta
7.9
Good
7,995 reviews

Boarding

8.2

Comfort

7.9

Overall

7.9

Entertainment

7.9

Food

7.3

Crew

8.5

Reviews

1 / 20
8.0
Excellent

Matthew,Oct 2025

GSP - ATL

This is always a full flight since it is the connecting route to primary destinations through Atlanta. That said, the crew handles the full load well. Not much more to say, it is a short flight with no in-flight services due to the length.

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 6 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 23h 30m. The distance from Washington, D.C. Dulles Intl Airport to Porto is about 3537 mi.

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

    Currently priced at $493, United Airlines will fly you from Washington, D.C. Dulles Intl Airport to Porto and back. In addition to United Airlines, many other airlines offer competitively priced options for your trip. Search Cheapflights for deals from TAP AIR PORTUGAL and Iberia - these airlines can fly you to your destination from $506 and $515, respectively. These flights start at 34% lower than the current average price 3 months from now.

  • 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, February is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to Porto (average of $406). Flying from Washington, D.C. Dulles Intl Airport to Porto in May is currently the most expensive (average of $688). 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
Aveiro
Arcos de Valdevez
Coimbra

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Top 6 airlines flying from Dulles Intl to Porto

Discover the top 6 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 October 28, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$493Average$783FlexibilityNo cancel feeOn-time69%
TAP AIR PORTUGALCheapest$506Average$790FlexibilityNo cancel feeOn-timeN/A
IberiaCheapest$515Average$672FlexibilityNo cancel feeOn-time77%
DeltaCheapest$533Average$875FlexibilityNo cancel feeOn-timeN/A
KLMCheapest$555Average$741FlexibilityNo cancel feeOn-time75%
LufthansaCheapest$618Average$693FlexibilityNo cancel feeOn-time76%

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