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$254+ 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 8/18. Fares are subject to change and may not be available on all flights or dates of travel.
IAD — OPO
May 4 — May 111
Sun 5/4
Sun 5/11
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 58 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 April 29, 2025.

Most accurate provider

AranGrant
3 stars

Most trusted provider

AranGrant
3 stars

Round-trip from

$675
(Mytrip)

One-way from

$355
(Kiwi.com)

Popular in

December

Cheapest in

February

Average price

$672
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
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High demand for flights, 2% potential price rise
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Cheapest flight prices on average. 2% potential price decrease ($16 potential savings vs. average RT price).
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Average for round-trip flights in April 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 April 29, 2025.

This oojo deal was found by Cheapflights users on 4/27. 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.
Thu 8/145:50 pmIAD - OPO
1 stop11h 10mTAP AIR PORTUGAL
Mon 8/256:05 pmOPO - IAD
1 stop26h 15mTAP AIR PORTUGAL
Deal found 4/27$664
This Mytrip deal was found by Cheapflights users on 4/27. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/129:45 amIAD - OPO
2 stops31h 40mMultiple Airlines
Wed 5/213:25 pmOPO - IAD
2 stops34h 43mMultiple Airlines
Deal found 4/27$669
This United Airlines deal was found by Cheapflights users on 4/27. 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.
Thu 10/308:35 amIAD - OPO
2 stops26h 40mUnited Airlines
Fri 11/712:30 pmOPO - IAD
2 stops37h 35mUnited Airlines
Deal found 4/27$670
This Gotogate deal was found by Cheapflights users on 4/27. 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 6/168:18 amIAD - OPO
2 stops20h 17mAir Canada
Tue 7/112:50 pmOPO - IAD
1 stop13h 11mAir Canada
Deal found 4/27$671
This SWISS deal was found by Cheapflights users on 4/27. 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.
Mon 5/128:45 pmIAD - OPO
1 stop30h 10mSWISS
Wed 5/2112:20 pmOPO - IAD
1 stop32h 55mSWISS
Deal found 4/27$711
This Delta deal was found by Cheapflights users on 4/27. 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 8/198:30 pmIAD - OPO
2 stops14h 00mDelta
Wed 8/276:15 amOPO - IAD
1 stop14h 20mDelta
Deal found 4/27$719
This KLM deal was found by Cheapflights users on 4/28. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/46:30 pmIAD - OPO
1 stop16h 00mKLM
Mon 8/116:25 pmOPO - IAD
1 stop26h 10mKLM
Deal found 4/28$725
This Lufthansa deal was found by Cheapflights users on 4/27. 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 Lufthansa is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/176:10 pmIAD - OPO
1 stop16h 35mLufthansa
Fri 6/2711:05 amOPO - IAD
1 stop13h 20mLufthansa
Deal found 4/27$741
This British Airways deal was found by Cheapflights users on 4/27. 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 British Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/178:14 pmIAD - OPO
2 stops18h 16mBritish Airways
Mon 6/239:10 pmOPO - IAD
1 stop28h 00mBritish Airways
Deal found 4/27$807
This Orbitz deal was found by Cheapflights users on 4/28. 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 Orbitz is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/1010:45 pmIAD - OPO
2 stops27h 50mIberia
Sat 10/188:15 amOPO - IAD
1 stop11h 45mIberia
Deal found 4/28$826

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 April 29, 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

Thu 8/14

5:50 pm-10:00 am

1 stop11h 10m

Porto

Mon 8/25

6:05 pm-3:20 pm

1 stop26h 15m

$664

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Mon 5/12

9:45 am-10:25 pm

2 stops31h 40m

Porto

Wed 5/21

3:25 pm-9:08 pm

2 stops34h 43m

$669

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Mon 6/16

8:18 am-9:35 am

2 stops20h 17m

Porto

Tue 7/1

12:50 pm-9:01 pm

1 stop13h 11m

$671

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Mon 7/14

5:31 pm-9:35 am

1 stop11h 04m

Porto

Tue 7/22

12:50 pm-11:53 am

2 stops28h 03m

$686

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Mon 5/12

8:45 pm-7:55 am

1 stop30h 10m

Porto

Wed 5/21

12:20 pm-4:15 pm

1 stop32h 55m

$711

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Tue 8/19

8:30 pm-3:30 pm

2 stops14h 00m

Porto

Wed 8/27

6:15 am-3:35 pm

1 stop14h 20m

$719

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Mon 8/4

6:30 pm-3:30 pm

1 stop16h 00m

Porto

Mon 8/11

6:25 pm-3:35 pm

1 stop26h 10m

$725

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Tue 6/17

6:10 pm-3:45 pm

1 stop16h 35m

Porto

Fri 6/27

11:05 am-7:25 pm

1 stop13h 20m

$741

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Tue 6/17

8:14 pm-7:30 pm

2 stops18h 16m

Porto

Mon 6/23

9:10 pm-8:10 pm

1 stop28h 00m

$807

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Fri 10/10

10:45 pm-7:35 am

2 stops27h 50m

Porto

Sat 10/18

8:15 am-3:00 pm

1 stop11h 45m

$826

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/27

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 April.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*2 stars
AranGrantPrice Accuracy3 starsTrust Score*3 stars
FlightnetworkPrice Accuracy3 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 AranGrant to be most consistent on Cheapflights vs. AranGrant Users can find the same prices on Washington, D.C. Dulles Intl Airport-Porto flight deals on Cheapflights vs. AranGrant >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 AranGrant the most. AranGrant 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 April 25, 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 58 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 $1,071). 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 April 29, 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 April 29, 2025.
To help decide which airline to fly from Washington, D.C. to Porto, see what other customers have to say about Porter Airlines, Delta and KLM. In addition to providing an overall rating, users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Porter Airlines
8.0
Very good
285 reviews

Crew

8.8

Entertainment

7.0

Comfort

8.1

Boarding

8.2

Food

7.6

Overall

8.0

Reviews

1 / 18
10.0
Excellent

Anonymous,Apr 2025

MCO - YHZ

A good flight and the crew was very nice. Thank you
Porter Airlines
8.0
Very good
285 reviews
Porter Airlines
8.0
Very good
285 reviews

Crew

8.8

Entertainment

7.0

Comfort

8.1

Boarding

8.2

Food

7.6

Overall

8.0

Reviews

1 / 18
10.0
Excellent

Anonymous,Apr 2025

MCO - YHZ

A good flight and the crew was very nice. Thank you
Delta
8.0
Very good
7,929 reviews
Porter Airlines
8.0
Very good
285 reviews

Crew

8.8

Entertainment

7.0

Comfort

8.1

Boarding

8.2

Food

7.6

Overall

8.0

Reviews

1 / 18
10.0
Excellent

Anonymous,Apr 2025

MCO - YHZ

A good flight and the crew was very nice. Thank you
KLM
7.8
Good
1,333 reviews
Porter Airlines
8.0
Very good
285 reviews

Crew

8.8

Entertainment

7.0

Comfort

8.1

Boarding

8.2

Food

7.6

Overall

8.0

Reviews

1 / 18
10.0
Excellent

Anonymous,Apr 2025

MCO - YHZ

A good flight and the crew was very nice. Thank you
SWISS
7.5
Good
1,587 reviews
Porter Airlines
8.0
Very good
285 reviews

Crew

8.8

Entertainment

7.0

Comfort

8.1

Boarding

8.2

Food

7.6

Overall

8.0

Reviews

1 / 18
10.0
Excellent

Anonymous,Apr 2025

MCO - YHZ

A good flight and the crew was very nice. Thank you
Air France
7.4
Good
1,444 reviews
Porter Airlines
8.0
Very good
285 reviews

Crew

8.8

Entertainment

7.0

Comfort

8.1

Boarding

8.2

Food

7.6

Overall

8.0

Reviews

1 / 18
10.0
Excellent

Anonymous,Apr 2025

MCO - YHZ

A good flight and the crew was very nice. Thank you

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 $678, 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 United Airlines and Air Canada - these airlines can fly you to your destination from $686 and $705, respectively. These flights start at 5% 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?

    $438 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 Air Canada and United Airlines, with prices starting from $549 and $554, 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 6.8 mi, respectively after landing at Lisbon Humberto Delgado. Travelers can book a car rental at Lisbon Humberto Delgado for about $22 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 $1,071). 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 April 29, 2025.
AirlineCheapestAverageFlexibilityOn-time
Air FranceCheapest$422Average$818FlexibilityNo cancel feeOn-time77%
DeltaCheapest$423Average$803FlexibilityNo cancel feeOn-timeN/A
KLMCheapest$435Average$661FlexibilityNo cancel feeOn-time75%
TAP AIR PORTUGALCheapest$457Average$738FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$538Average$843FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$567Average$828FlexibilityNo cancel feeOn-time71%
IberiaCheapest$579Average$798FlexibilityNo cancel feeOn-time77%
LufthansaCheapest$603Average$754FlexibilityNo cancel feeOn-time76%

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