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$331+ 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 5/26. Fares are subject to change and may not be available on all flights or dates of travel.
IAD — OPO
Apr 2 — Apr 91
Wed 4/2
Wed 4/9
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 41 days in advance, depart on a Sunday or Saturday and return on a Monday

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 March 28, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$623
(Kiwi.com)

One-way from

$331
(Mytrip)

Popular in

June

Cheapest in

February

Average price

$671
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
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One-way flight from Washington, D.C. Dulles Intl to Porto
Search Deals
Highest demand for flights based on searches. 21% potential increase in price ($195 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($25 potential savings vs. average RT price).
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Average for round-trip flights in March 2025
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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 March 28, 2025.

This Lufthansa deal was found by Cheapflights users on 3/26. 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 Lufthansa is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 11/165:50 pmIAD - OPO
2 stops14h 00mLufthansa
Sun 11/236:15 amOPO - IAD
1 stop18h 50mLufthansa
Deal found 3/26$618
This FlightHub deal was found by Cheapflights users on 3/27. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/255:50 pmIAD - OPO
1 stop11h 10mTAP AIR PORTUGAL
Sun 10/510:30 pmOPO - IAD
1 stop27h 20mTAP AIR PORTUGAL
Deal found 3/27$619
This SWISS deal was found by Cheapflights users on 3/27. 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 SWISS is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/138:45 pmIAD - OPO
1 stop33h 25mSWISS
Sun 11/166:35 pmOPO - IAD
2 stops50h 55mSWISS
Deal found 3/27$625
This Iberia deal was found by Cheapflights users on 3/27. 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 Iberia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/310:40 pmIAD - OPO
1 stop15h 50mMultiple Airlines
Tue 6/108:15 amOPO - IAD
1 stop11h 45mMultiple Airlines
Deal found 3/27$626
This Cheapflightsfares deal was found by Cheapflights users on 3/27. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/274:35 pmIAD - OPO
1 stop10h 00mIberia
Mon 6/98:35 pmOPO - IAD
1 stop23h 25mIberia
Deal found 3/27$642
This United Airlines deal was found by Cheapflights users on 3/26. 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.
Tue 12/235:15 pmIAD - OPO
2 stops41h 00mUnited Airlines
Tue 12/306:00 amOPO - IAD
1 stop13h 40mUnited Airlines
Deal found 3/26$644
This Gurufare deal was found by Cheapflights users on 3/27. 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 Gurufare is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/810:05 pmIAD - OPO
1 stop31h 55mScandinavian Airlines
Mon 10/612:00 pmOPO - IAD
1 stop12h 59mScandinavian Airlines
Deal found 3/27$660
This oojo deal was found by Cheapflights users on 3/27. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/231:30 pmIAD - OPO
1 stop21h 20mTurkish Airlines
Wed 4/304:50 pmOPO - IAD
1 stop31h 55mTurkish Airlines
Deal found 3/27$671
This Booking.com deal was found by Cheapflights users on 3/27. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/249:55 amIAD - OPO
1 stop18h 30mAir Canada
Tue 10/76:00 amOPO - IAD
2 stops20h 01mAir Canada
Deal found 3/27$681
This Delta deal was found by Cheapflights users on 3/27. 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.
Mon 9/812:30 pmIAD - OPO
2 stops22h 00mDelta
Wed 10/19:15 pmOPO - IAD
1 stop23h 20mDelta
Deal found 3/27$712
This Mytrip deal was found by Cheapflights users on 3/26. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 6/154:20 pmIAD - OPO
2 stops33h 25mAir Transat
Fri 6/278:25 amOPO - IAD
2 stops35h 41mAir Transat
Deal found 3/26$742
This Expedia deal was found by Cheapflights users on 3/27. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 6/110:40 pmIAD - OPO
2 stops27h 55mBritish Airways
Sat 6/148:15 amOPO - IAD
1 stop11h 45mBritish Airways
Deal found 3/27$750

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 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 6/3

10:40 pm-7:30 pm

1 stop15h 50m

Porto

Tue 6/10

8:15 am-3:00 pm

1 stop11h 45m

$626

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Tue 5/27

4:35 pm-7:35 am

1 stop10h 00m

Porto

Mon 6/9

8:35 pm-3:00 pm

1 stop23h 25m

$642

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Wed 4/23

1:30 pm-3:50 pm

1 stop21h 20m

Porto

Wed 4/30

4:50 pm-7:45 pm

1 stop31h 55m

$671

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Mon 5/12

6:10 pm-11:15 am

1 stop12h 05m

Porto

Mon 5/19

6:15 am-7:25 pm

1 stop18h 10m

$689

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Mon 6/16

9:45 am-9:35 am

1 stop18h 50m

Porto

Tue 6/24

12:50 pm-11:53 am

2 stops28h 03m

$694

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Sun 4/6

10:20 pm-5:00 pm

1 stop13h 40m

Porto

Thu 4/17

7:00 am-3:20 pm

1 stop13h 20m

$704

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Sun 6/15

10:40 pm-8:25 pm

1 stop16h 45m

Porto

Thu 6/26

8:15 am-3:00 pm

1 stop11h 45m

$712

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Mon 6/16

10:20 am-9:35 am

2 stops18h 15m

Porto

Thu 6/26

12:10 pm-4:20 pm

2 stops33h 10m

$713

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Tue 4/15

5:25 pm-3:35 pm

1 stop17h 10m

Porto

Tue 6/3

11:25 am-11:35 pm

2 stops17h 10m

$729

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Mon 5/12

8:45 pm-1:45 pm

2 stops36h 00m

Porto

Mon 5/19

12:50 pm-4:15 pm

1 stop32h 25m

$738

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/26

Showing 1-10 of 22 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 March.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
AranGrantPrice Accuracy3 starsTrust Score*1 star
FlightnetworkPrice Accuracy2 starsTrust Score*3 stars
FlightsMojoPrice Accuracy-Trust Score*3 stars
Trip.comPrice Accuracy1 starTrust 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 21, 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 41 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 $523). Flying from Washington, D.C. Dulles Intl Airport to Porto in June is currently the most expensive (average of $1,084). 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 March 28, 2025.

It’s typically best to fly out from Washington, D.C. Dulles Intl Airport to Porto in the morning. Doing so could potentially save you 23% on the flight price compared to flying in the afternoon, which is usually more expensive.

Rainfall in Porto by month

Plan your trip to Porto by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Porto ranges from 0.7 - 7.7 inches per month. December is typically the wettest month, when rainfall can reach 7.7 in. July is typically the driest time to visit Porto when rainfall is around 0.7 in.

Temperature in Porto by month

Plan your trip to Porto by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Porto, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 68.0 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 48.2 F).

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 28, 2025.
To help decide which airline to fly from Washington, D.C. to Porto, see what other customers have to say about Delta, KLM and Air Transat. In addition to providing an overall rating, users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Delta
8.0
Very good
7,896 reviews

Entertainment

7.9

Overall

8.0

Food

7.3

Comfort

8.0

Boarding

8.2

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
Delta
8.0
Very good
7,896 reviews
Delta
8.0
Very good
7,896 reviews

Entertainment

7.9

Overall

8.0

Food

7.3

Comfort

8.0

Boarding

8.2

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
KLM
7.8
Good
1,321 reviews
Delta
8.0
Very good
7,896 reviews

Entertainment

7.9

Overall

8.0

Food

7.3

Comfort

8.0

Boarding

8.2

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
Air Transat
7.8
Good
381 reviews
Delta
8.0
Very good
7,896 reviews

Entertainment

7.9

Overall

8.0

Food

7.3

Comfort

8.0

Boarding

8.2

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
SWISS
7.5
Good
1,570 reviews
Delta
8.0
Very good
7,896 reviews

Entertainment

7.9

Overall

8.0

Food

7.3

Comfort

8.0

Boarding

8.2

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
United Airlines
7.4
Good
8,603 reviews
Delta
8.0
Very good
7,896 reviews

Entertainment

7.9

Overall

8.0

Food

7.3

Comfort

8.0

Boarding

8.2

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

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.

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

    Currently priced at $623, TAP AIR PORTUGAL will fly you from Washington, D.C. Dulles Intl Airport to Porto and back. In addition to TAP AIR PORTUGAL, many other airlines offer competitively priced options for your trip. Search Cheapflights for deals from Iberia and Scandinavian Airlines - these airlines can fly you to your destination from $642 and $660, respectively. These flights start at 14% 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?

    $433 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 Scandinavian Airlines and Air Canada, with prices starting from $489 and $549, respectively.

  • Where are the most common layover locations when flying from Washington, D.C. Dulles Intl Airport to Porto?

    Flights departing from Washington, D.C. Dulles Intl Airport and landing in Porto layover in Lisbon most frequently.

  • What are some popular things to do or see while on a layover in Lisbon?

    Most Lisbon visitors opt to spend their time experiencing Chiado, Praça do Marquês de Pombal, and Centro Cultural de Belém. Travelers on a layover in Lisbon can visit Chiado, Praça do Marquês de Pombal, and Centro Cultural de Belém, by traveling 4.5 mi, 3.6 mi, and 6.9 mi, respectively after landing at Lisbon Humberto Delgado. Travelers can book a car rental at Lisbon Humberto Delgado for about $21 per day to make their sightseeing more efficient.

  • Where are the least popular layover locations for Washington, D.C. Dulles Intl Airport to Porto flights?

    Washington, D.C. Dulles Intl Airport to Porto flights have a layover in Madrid least often.

  • 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 $523). Flying from Washington, D.C. Dulles Intl Airport to Porto in June is currently the most expensive (average of $1,084). 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 Washington, D.C. Dulles Intl Airport?

Book flights to Washington, D.C. Dulles Intl Airport if you plan to visit one of these locations
Aveiro
Coimbra
Matosinhos
Arcos de Valdevez

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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 28, 2025.
AirlineCheapestAverageFlexibilityOn-time
Air FranceCheapest$422Average$818FlexibilityNo cancel feeOn-time77%
DeltaCheapest$423Average$803FlexibilityNo cancel feeOn-timeN/A
KLMCheapest$435Average$663FlexibilityNo cancel feeOn-time75%
TAP AIR PORTUGALCheapest$458Average$763FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$538Average$970FlexibilityNo cancel feeOn-time69%
LufthansaCheapest$538Average$693FlexibilityNo cancel feeOn-time76%
American AirlinesCheapest$567Average$828FlexibilityNo cancel feeOn-time71%
IberiaCheapest$579Average$798FlexibilityNo cancel feeOn-time77%
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