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$313+ 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 11/18. Fares are subject to change and may not be available on all flights or dates of travel.
IAD — OPO
Jul 10 — Jul 171
Fri 7/10
Fri 7/17
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 June 10, 2026.

This Kiwi.com deal was found by Cheapflights users on 6/9. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 7/198:30 pm
IAD
-
OPO
2 stops20h 55m
Multiple Airlines
Fri 7/241:30 pm
OPO
-
IAD
1 stop25h 55m
Multiple Airlines
Deal found 6/9$906
This United Airlines deal was found by Cheapflights users on 6/8. 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 7/1412:35 pm
IAD
-
OPO
1 stop12h 40m
United Airlines
Tue 7/2112:15 pm
OPO
-
IAD
2 stops28h 37m
United Airlines
Deal found 6/8$907
This United Airlines deal was found by Cheapflights users on 6/8. 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.
Wed 8/263:45 pm
IAD
-
OPO
1 stop10h 15m
United Airlines
Fri 9/256:00 am
OPO
-
IAD
1 stop19h 00m
United Airlines
Deal found 6/8$908
This oojo deal was found by Cheapflights users on 6/9. 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.
Tue 7/710:20 pm
IAD
-
OPO
1 stop20h 05m
Lufthansa
Tue 8/411:05 am
OPO
-
IAD
1 stop13h 20m
Lufthansa
Deal found 6/9$909
This United Airlines deal was found by Cheapflights users on 6/9. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/710:10 pm
IAD
-
OPO
2 stops27h 50m
United Airlines
Wed 7/2911:20 am
OPO
-
IAD
2 stops34h 12m
United Airlines
Deal found 6/9$910
This Mytrip deal was found by Cheapflights users on 6/9. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/48:20 pm
IAD
-
OPO
3 stops22h 10m
Multiple Airlines
Tue 9/810:00 pm
OPO
-
IAD
3 stops24h 00m
Multiple Airlines
Deal found 6/9$911
This Turkish Airlines deal was found by Cheapflights users on 6/8. 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 Turkish Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/281:20 pm
IAD
-
OPO
1 stop21h 20m
Turkish Airlines
Thu 9/244:40 pm
OPO
-
IAD
1 stop23h 55m
Turkish Airlines
Deal found 6/8$912
This KAYAK deal was found by Cheapflights users on 6/9. 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 KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/2510:55 pm
IAD
-
OPO
2 stops18h 30m
Lufthansa
Wed 12/306:00 am
OPO
-
IAD
1 stop14h 55m
Lufthansa
Deal found 6/9$913
This United Airlines deal was found by Cheapflights users on 6/9. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/156:33 am
IAD
-
OPO
2 stops19h 27m
United Airlines
Wed 7/226:00 am
OPO
-
IAD
1 stop15h 05m
United Airlines
Deal found 6/9$914
This Delta deal was found by Cheapflights users on 6/8. 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 7/76:59 pm
IAD
-
OPO
2 stops15h 26m
Delta
Wed 7/155:00 am
OPO
-
IAD
1 stop15h 35m
Delta
Deal found 6/8$915
This Air Canada deal was found by Cheapflights users on 6/8. 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 Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 8/2310:10 pm
IAD
-
OPO
2 stops27h 50m
Air Canada
Thu 9/2412:10 pm
OPO
-
IAD
2 stops28h 11m
Air Canada
Deal found 6/8$916
This FlightHub deal was found by Cheapflights users on 6/9. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/710:14 pm
IAD
-
OPO
2 stops27h 46m
Multiple Airlines
Tue 8/46:20 am
OPO
-
IAD
1 stop18h 05m
Multiple Airlines
Deal found 6/9$917

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 June 10, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$906
(Kiwi.com)

One-way from

$313
(Kiwi.com)

Popular in

May

Cheapest in

October

Average price

$1,066
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. 18% potential increase in price ($184 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 4% potential price decrease ($38 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in June 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 June 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 7/15

8:25 am-7:00 am

2 stops17h 35m

Porto

Thu 7/23

6:00 am-4:05 pm

1 stop15h 05m

$914

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Wed 7/15

6:33 am-7:00 am

2 stops19h 27m

Porto

Wed 7/22

6:00 am-4:05 pm

1 stop15h 05m

$914

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Sun 8/2

9:45 pm-3:30 pm

1 stop12h 45m

Porto

Tue 8/18

5:00 am-8:05 pm

2 stops20h 05m

$919

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Tue 7/7

6:59 pm-3:25 pm

2 stops15h 26m

Porto

Tue 8/4

5:00 am-6:33 pm

2 stops18h 33m

$924

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Wed 7/15

6:59 pm-10:00 pm

2 stops22h 01m

Porto

Fri 7/24

5:00 am-6:19 pm

2 stops18h 19m

$924

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Thu 9/17

12:25 pm-8:30 am

2 stops15h 05m

Porto

Mon 9/21

5:00 am-5:33 pm

2 stops17h 33m

$927

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Tue 8/11

7:19 pm-3:25 pm

2 stops15h 06m

Porto

Tue 8/18

6:15 am-6:33 pm

2 stops17h 18m

$931
Quickest round-trip

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Sun 7/19

10:35 pm-7:00 pm

1 stop15h 25m

Porto

Thu 7/23

5:05 am-3:10 pm

1 stop15h 05m

$959

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Thu 8/6

6:33 am-6:55 am

1 stop19h 22m

Porto

Fri 8/14

6:00 am-4:05 pm

1 stop15h 05m

$971

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Thu 7/16

5:46 pm-3:25 pm

2 stops16h 39m

Porto

Thu 7/23

5:00 am-3:35 pm

1 stop15h 35m

$974

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/5

Showing 1-10 of 20 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 June.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
AranGrantPrice Accuracy3 starsTrust Score*3 stars
OvagoPrice 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 77 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, October is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to Porto (average of $530). Flying from Washington, D.C. Dulles Intl Airport to Porto in May is currently the most expensive (average of $1,214). 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 June 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
8,393 reviews

Boarding

8.1

Crew

8.5

Entertainment

7.8

Overall

7.9

Food

7.2

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Anonymous,May 2026

SEA - KOA

The snacks were not very good, not everyone was very friendly and professional
Delta
7.9
Good
8,393 reviews
Delta
7.9
Good
8,393 reviews

Boarding

8.1

Crew

8.5

Entertainment

7.8

Overall

7.9

Food

7.2

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Anonymous,May 2026

SEA - KOA

The snacks were not very good, not everyone was very friendly and professional
United Airlines
7.4
Good
9,802 reviews
Delta
7.9
Good
8,393 reviews

Boarding

8.1

Crew

8.5

Entertainment

7.8

Overall

7.9

Food

7.2

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Anonymous,May 2026

SEA - KOA

The snacks were not very good, not everyone was very friendly and professional
TAP AIR PORTUGAL
7.2
Good
2,274 reviews
Delta
7.9
Good
8,393 reviews

Boarding

8.1

Crew

8.5

Entertainment

7.8

Overall

7.9

Food

7.2

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Anonymous,May 2026

SEA - KOA

The snacks were not very good, not everyone was very friendly and professional
Iberia
7.0
Good
3,232 reviews
Delta
7.9
Good
8,393 reviews

Boarding

8.1

Crew

8.5

Entertainment

7.8

Overall

7.9

Food

7.2

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Anonymous,May 2026

SEA - KOA

The snacks were not very good, not everyone was very friendly and professional
Lufthansa
6.8
Okay
8,052 reviews
Delta
7.9
Good
8,393 reviews

Boarding

8.1

Crew

8.5

Entertainment

7.8

Overall

7.9

Food

7.2

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Anonymous,May 2026

SEA - KOA

The snacks were not very good, not everyone was very friendly and professional

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 12h 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 $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 $493 and $496, respectively. These flights start at 40% 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?

    $250 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 Lufthansa and KLM, with prices starting from $273 and $356, 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, October is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to Porto (average of $530). Flying from Washington, D.C. Dulles Intl Airport to Porto in May is currently the most expensive (average of $1,214). 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.
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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 June 10, 2026.
AirlineCheapestAverageFlexibilityOn-time
KLMCheapest$477Average$883FlexibilityNo cancel feeOn-time75%
United AirlinesCheapest$493Average$848FlexibilityNo cancel feeOn-time69%
TAP AIR PORTUGALCheapest$496Average$785FlexibilityNo cancel feeOn-timeN/A
LufthansaCheapest$514Average$709FlexibilityNo cancel feeOn-time76%
IberiaCheapest$515Average$664FlexibilityNo cancel feeOn-time77%
DeltaCheapest$533Average$1,048FlexibilityNo cancel feeOn-timeN/A

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