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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 10/20. Fares are subject to change and may not be available on all flights or dates of travel.
IAD — OPO
Sep 14 — Sep 211
Mon 9/14
Mon 9/21
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 August 15, 2026.

This Gotogate deal was found by Cheapflights users on 8/11. 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.
Wed 10/710:35 pm -
1 stop15h 25m
Tue 10/137:00 am -
1 stop13h 10m
Deal found 8/11$674
This Booking.com deal was found by Cheapflights users on 8/12. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/1110:30 pm -
1 stop10h 00m
Mon 11/238:00 pm -
1 stop23h 45m
Deal found 8/12$675
This Kiwi.com deal was found by Cheapflights users on 8/15. 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.
Sat 10/318:40 pm -
2 stops16h 50m
Mon 11/168:20 am -
1 stop13h 00m
Deal found 8/15$677
This CheapTickets.ch deal was found by Cheapflights users on 8/13. 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 CheapTickets.ch is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/275:40 pm -
1 stop10h 20m
Sun 10/49:15 pm -
1 stop22h 55m
Deal found 8/13$678
This FlightHub deal was found by Cheapflights users on 8/11. 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.
Mon 11/95:25 pm -
1 stop12h 35m
Tue 11/178:30 am -
1 stop11h 15m
Deal found 8/11$679
This Kiwi.com deal was found by Cheapflights users on 8/14. 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.
Sat 10/108:30 pm -
2 stops14h 05m
Wed 10/218:20 am -
1 stop12h 10m
Deal found 8/14$683
This Justfly.com deal was found by Cheapflights users on 8/12. 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 Justfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/1110:30 pm -
1 stop10h 00m
Wed 11/187:00 am -
1 stop18h 35m
Deal found 8/12$684
This Kiwi.com deal was found by Cheapflights users on 8/13. 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.
Fri 10/23:50 pm -
2 stops24h 00m
Tue 10/208:20 am -
1 stop15h 30m
Deal found 8/13$686
This Kiwi.com deal was found by Cheapflights users on 8/15. 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 10/68:30 pm -
2 stops37h 35m
Wed 10/148:20 am -
1 stop12h 10m
Deal found 8/15$688
This TAP AIR PORTUGAL deal was found by Cheapflights users on 8/13. 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.
Sun 10/1810:35 pm -
1 stop17h 00m
Sat 10/249:00 am -
1 stop11h 10m
Deal found 8/13$689
This Kiwi.com deal was found by Cheapflights users on 8/12. 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 11/17:40 pm -
2 stops18h 10m
Tue 11/178:20 am -
1 stop13h 00m
Deal found 8/12$693
This Kiwi.com deal was found by Cheapflights users on 8/15. 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 9/288:30 pm -
2 stops19h 10m
Tue 10/138:20 am -
1 stop15h 30m
Deal found 8/15$696

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 August 15, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$674
(Gotogate)

One-way from

$269
(Kiwi.com)

Popular in

May

Cheapest in

January

Average price

$814
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
Highest demand for flights based on searches. 16% potential increase in price ($160 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 4% potential price decrease ($37 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in August 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 August 15, 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 Washington, D.C. Dulles Intl - OPO Porto

IADOPO

Washington, D.C. Dulles Intl

Mon 11/16

8:37 am-9:30 am

1 stop19h 53m

Porto

Fri 11/20

6:00 am-8:05 pm

1 stop19h 05m

$731

Washington, D.C.Porto

IAD Washington, D.C. Dulles Intl - OPO Porto

IADOPO

Washington, D.C. Dulles Intl

Tue 12/8

12:35 pm-10:35 am

2 stops17h 00m

Porto

Wed 12/16

5:00 am-3:55 pm

1 stop15h 55m

$737

Washington, D.C.Porto

IAD Washington, D.C. Dulles Intl - OPO Porto

IADOPO

Washington, D.C. Dulles Intl

Wed 11/11

12:30 pm-9:05 am

2 stops15h 35m

Porto

Fri 11/20

5:00 am-3:55 pm

1 stop15h 55m

$738

Washington, D.C.Porto

IAD Washington, D.C. Dulles Intl - OPO Porto

IADOPO

Washington, D.C. Dulles Intl

Wed 11/11

12:30 pm-9:05 am

2 stops15h 35m

Porto

Wed 11/18

11:15 am-3:45 pm

1 stop33h 30m

$738

Washington, D.C.Porto

IAD Washington, D.C. Dulles Intl - OPO Porto

IADOPO

Washington, D.C. Dulles Intl

Sun 11/22

10:19 pm-11:45 am

2 stops32h 26m

Porto

Fri 11/27

6:00 am-10:25 pm

2 stops21h 25m

$766

Washington, D.C.Porto

IAD Washington, D.C. Dulles Intl - OPO Porto

IADOPO

Washington, D.C. Dulles Intl

Sat 11/7

10:20 pm-3:25 pm

1 stop36h 05m

Porto

Tue 11/17

4:25 pm-11:45 am

1 stop24h 20m

$843
Quickest round-trip

Washington, D.C.Porto

IAD Washington, D.C. Dulles Intl - OPO Porto

IADOPO

Washington, D.C. Dulles Intl

Mon 11/9

6:15 pm-10:30 am

1 stop11h 15m

Porto

Sun 11/15

5:00 am-3:45 pm

1 stop15h 45m

$847

Washington, D.C.Porto

IAD Washington, D.C. Dulles Intl - OPO Porto

IADOPO

Washington, D.C. Dulles Intl

Fri 11/20

10:15 am-3:20 pm

2 stops24h 05m

Porto

Wed 11/25

6:00 am-4:24 pm

2 stops39h 24m

$879

Washington, D.C.Porto

IAD Washington, D.C. Dulles Intl - OPO Porto

IADOPO

Washington, D.C. Dulles Intl

Sun 9/13

8:35 am-6:55 am

1 stop17h 20m

Porto

Wed 9/23

11:20 am-11:25 am

2 stops29h 05m

$907

Washington, D.C.Porto

IAD Washington, D.C. Dulles Intl - OPO Porto

IADOPO

Washington, D.C. Dulles Intl

Tue 9/8

3:40 pm-3:25 pm

2 stops18h 45m

Porto

Tue 9/15

5:00 am-3:35 pm

1 stop15h 35m

$914

Flights are sorted by cheapest round-trip flights first.

Deals found on 8/10

Showing 1-10 of 17 resultsSorted by cheapest first
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 August.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
OvagoPrice Accuracy3 starsTrust Score*3 stars
AranGrantPrice Accuracy3 starsTrust Score*3 stars
eDreamsPrice 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 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?

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 23 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, January is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to Porto (average of $613). Flying from Washington, D.C. Dulles Intl Airport to Porto in May is currently the most expensive (average of $1,227). 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?

Airfare is below average for this route at the moment.

Washington, D.C. Dulles Intl Airport to Porto flights typically cost between $690 and $925 in October.
The cheapest round-trip price found within the last 5 days was $674 on TAP AIR PORTUGAL (Oct 7-Oct 13).

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 August 15, 2026.
Get a feel of what it's like to fly with KLM,Delta, andUnited Airlines 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.
KLM
7.8
Good
1,559 reviews

Boarding

7.8

Food

7.3

Crew

8.4

Overall

7.8

Comfort

7.7

Entertainment

7.2

Reviews

1 / 20
4.0
Okay

Abhisek,Aug 2026

JFK - AMS

They didn’t offer any options for breakfast and had only one option which was cold meat and cheese. I would expect at least one more option in premium economy
KLM
7.8
Good
1,559 reviews
KLM
7.8
Good
1,559 reviews

Boarding

7.8

Food

7.3

Crew

8.4

Overall

7.8

Comfort

7.7

Entertainment

7.2

Reviews

1 / 20
4.0
Okay

Abhisek,Aug 2026

JFK - AMS

They didn’t offer any options for breakfast and had only one option which was cold meat and cheese. I would expect at least one more option in premium economy
Delta
7.8
Good
8,508 reviews
KLM
7.8
Good
1,559 reviews

Boarding

7.8

Food

7.3

Crew

8.4

Overall

7.8

Comfort

7.7

Entertainment

7.2

Reviews

1 / 20
4.0
Okay

Abhisek,Aug 2026

JFK - AMS

They didn’t offer any options for breakfast and had only one option which was cold meat and cheese. I would expect at least one more option in premium economy
United Airlines
7.4
Good
10,110 reviews
KLM
7.8
Good
1,559 reviews

Boarding

7.8

Food

7.3

Crew

8.4

Overall

7.8

Comfort

7.7

Entertainment

7.2

Reviews

1 / 20
4.0
Okay

Abhisek,Aug 2026

JFK - AMS

They didn’t offer any options for breakfast and had only one option which was cold meat and cheese. I would expect at least one more option in premium economy
TAP AIR PORTUGAL
7.2
Good
2,368 reviews
KLM
7.8
Good
1,559 reviews

Boarding

7.8

Food

7.3

Crew

8.4

Overall

7.8

Comfort

7.7

Entertainment

7.2

Reviews

1 / 20
4.0
Okay

Abhisek,Aug 2026

JFK - AMS

They didn’t offer any options for breakfast and had only one option which was cold meat and cheese. I would expect at least one more option in premium economy
Lufthansa
6.8
Okay
8,195 reviews
KLM
7.8
Good
1,559 reviews

Boarding

7.8

Food

7.3

Crew

8.4

Overall

7.8

Comfort

7.7

Entertainment

7.2

Reviews

1 / 20
4.0
Okay

Abhisek,Aug 2026

JFK - AMS

They didn’t offer any options for breakfast and had only one option which was cold meat and cheese. I would expect at least one more option in premium economy

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 5 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 17h. 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 $477, KLM will fly you from Washington, D.C. Dulles Intl Airport to Porto and back. In addition to KLM, many other airlines offer competitively priced options for your trip. Search Cheapflights for deals from United Airlines and TAP AIR PORTUGAL - these airlines can fly you to your destination from $480 and $497, respectively. These flights start at 42% 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, January is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to Porto (average of $613). Flying from Washington, D.C. Dulles Intl Airport to Porto in May is currently the most expensive (average of $1,227). 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
Arcos de Valdevez
Coimbra
Aveiro

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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 5 airlines flying from Dulles Intl to Porto

Discover the top 5 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 August 15, 2026.
AirlineCheapestAverageFlexibilityOn-time
KLMCheapest$477Average$1,021FlexibilityNo cancel feeOn-time75%
United AirlinesCheapest$480Average$1,022FlexibilityNo cancel feeOn-time69%
TAP AIR PORTUGALCheapest$497Average$803FlexibilityNo cancel feeOn-timeN/A
LufthansaCheapest$514Average$724FlexibilityNo cancel feeOn-time76%
DeltaCheapest$533Average$1,187FlexibilityNo cancel feeOn-timeN/A

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