Dulles Intl

$351+ Cheap flights from Porto (OPO) to Dulles Intl (IAD)

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 9/9. Fares are subject to change and may not be available on all flights or dates of travel.
OPO — IAD
Jul 8 — Jul 151
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Cheap flight deals from Porto to Dulles Intl

Discover tips and strategies to find the most affordable flight options for your journey from Porto (OPO) to Dulles Intl (IAD). 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 July 3, 2025.

Round-trip from

$500
(oojo)

One-way from

$351
(Kiwi.com)

Popular in

June

Cheapest in

January

Average price

$740
From Porto to Washington, D.C. Dulles Intl
One-way flight from Porto to Washington, D.C. Dulles Intl
Highest demand for flights based on searches. 10% potential increase in price ($80 potential increase over avg. RT price).
Cheapest flight prices on average. 1% potential price decrease ($14 potential savings vs. average RT price).
Average for round-trip flights in July 2025

Find flight deals from Porto to Dulles Intl

Cheapest flights from Porto to Dulles Intl
Explore the most affordable flight options available from Porto to Dulles Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 3, 2025.

This oojo deal was found by Cheapflights users on 7/1. 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 10/19:00 amOPO - IAD
1 stop16h 50mTAP AIR PORTUGAL
Sat 10/1110:35 pmIAD - OPO
1 stop15h 25mTAP AIR PORTUGAL
Deal found 7/1$500
This United Airlines deal was found by Cheapflights users on 7/1. 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.
Fri 10/36:00 amOPO - IAD
1 stop14h 50mUnited Airlines
Sat 10/115:12 pmIAD - OPO
1 stop11h 33mUnited Airlines
Deal found 7/1$567
This Lufthansa deal was found by Cheapflights users on 7/1. 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.
Fri 10/36:00 amOPO - IAD
1 stop14h 50mLufthansa
Mon 10/1310:20 pmIAD - OPO
1 stop20h 00mLufthansa
Deal found 7/1$571
This American Airlines deal was found by Cheapflights users on 7/3. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/88:15 amOPO - IAD
1 stop11h 45mAmerican Airlines
Tue 10/2110:25 amIAD - OPO
2 stops16h 10mAmerican Airlines
Deal found 7/3$572
This SWISS deal was found by Cheapflights users on 7/1. 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 9/297:20 pmOPO - IAD
1 stop25h 55mSWISS
Sun 10/128:45 pmIAD - OPO
1 stop30h 10mSWISS
Deal found 7/1$589
This Air Canada deal was found by Cheapflights users on 7/2. 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.
Wed 10/16:00 amOPO - IAD
2 stops20h 05mAir Canada
Sat 10/111:00 pmIAD - OPO
2 stops17h 30mAir Canada
Deal found 7/2$592
This Iberia deal was found by Cheapflights users on 7/1. 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.
Sun 9/284:35 pmOPO - IAD
1 stop27h 25mIberia
Mon 10/1310:45 pmIAD - OPO
2 stops27h 50mIberia
Deal found 7/1$599
This Gotogate deal was found by Cheapflights users on 7/3. 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 8/257:20 pmOPO - IAD
1 stop25h 55mMultiple Airlines
Sun 9/76:10 pmIAD - OPO
1 stop23h 40mMultiple Airlines
Deal found 7/3$603
This Delta deal was found by Cheapflights users on 7/1. 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 9/306:15 amOPO - IAD
2 stops18h 22mDelta
Fri 10/109:20 pmIAD - OPO
1 stop13h 10mDelta
Deal found 7/1$606
This Austrian Airlines deal was found by Cheapflights users on 7/1. 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 Austrian Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/286:35 pmOPO - IAD
1 stop25h 00mAustrian Airlines
Fri 10/105:25 pmIAD - OPO
1 stop19h 30mAustrian Airlines
Deal found 7/1$614

Cheapflights Fare Finder

Customize your flight search to find flights from Porto to Dulles Intl 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 July 3, 2025.
Use the filters below to find and compare flights from Porto to Washington, D.C. Dulles Intl Airport that are best for you.

Fly from

Porto

Fly to

Dulles Intl

Route

Depart

Return

Price

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Wed 10/1

9:00 am-8:50 pm

1 stop16h 50m

Washington, D.C. Dulles Intl

Sat 10/11

10:35 pm-7:00 pm

1 stop15h 25m

$500

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Fri 10/3

6:00 am-3:50 pm

1 stop14h 50m

Washington, D.C. Dulles Intl

Sat 10/11

5:12 pm-9:45 am

1 stop11h 33m

$567

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Fri 10/3

6:00 am-3:50 pm

1 stop14h 50m

Washington, D.C. Dulles Intl

Mon 10/13

10:20 pm-11:20 pm

1 stop20h 00m

$571

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Wed 10/8

8:15 am-3:00 pm

1 stop11h 45m

Washington, D.C. Dulles Intl

Tue 10/21

10:25 am-7:35 am

2 stops16h 10m

$572

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Mon 9/29

7:20 pm-4:15 pm

1 stop25h 55m

Washington, D.C. Dulles Intl

Mon 10/13

8:45 pm-11:30 am

1 stop33h 45m

$589

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Wed 10/1

6:00 am-9:05 pm

2 stops20h 05m

Washington, D.C. Dulles Intl

Sat 10/11

1:00 pm-11:30 am

2 stops17h 30m

$592

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Sun 9/28

4:35 pm-3:00 pm

1 stop27h 25m

Washington, D.C. Dulles Intl

Mon 10/13

10:45 pm-7:35 am

2 stops27h 50m

$599

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Mon 8/25

7:20 pm-4:15 pm

1 stop25h 55m

Washington, D.C. Dulles Intl

Sun 9/7

6:10 pm-10:50 pm

1 stop23h 40m

$603

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Tue 9/30

6:15 am-7:37 pm

2 stops18h 22m

Washington, D.C. Dulles Intl

Fri 10/10

9:20 pm-3:30 pm

1 stop13h 10m

$606

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Sun 9/28

6:35 pm-2:35 pm

1 stop25h 00m

Washington, D.C. Dulles Intl

Fri 10/10

5:25 pm-5:55 pm

1 stop19h 30m

$614

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/2

Showing 1-10 of 15 results
1
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Best time to book a flight from Porto to Dulles Intl

Have a flexible travel schedule? Discover the best time to fly to Dulles Intl from Porto 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 Porto to Washington, D.C. Dulles Intl Airport

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

Find hourly flight availability from Porto to Dulles Intl. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated July 3, 2025.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Porto to Washington, D.C. Dulles Intl Airport as you normally would.

Reviews of airlines servicing Dulles Intl

Get insights into the airlines that provide service to Dulles Intl. 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 Dulles Intl. Reviews last updated July 3, 2025.
Get a feel of what it's like to fly with Delta, Austrian Airlines, and SWISS from Porto to Washington, D.C. Dulles Intl Airport by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
8.0
Very good

Boarding

8.2

Food

7.3

Crew

8.5

Comfort

7.9

Entertainment

7.9

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
8.0
Very good
8.0
Very good

Boarding

8.2

Food

7.3

Crew

8.5

Comfort

7.9

Entertainment

7.9

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
8.0
Very good

Boarding

8.2

Food

7.3

Crew

8.5

Comfort

7.9

Entertainment

7.9

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
8.0
Very good

Boarding

8.2

Food

7.3

Crew

8.5

Comfort

7.9

Entertainment

7.9

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
8.0
Very good

Boarding

8.2

Food

7.3

Crew

8.5

Comfort

7.9

Entertainment

7.9

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
8.0
Very good

Boarding

8.2

Food

7.3

Crew

8.5

Comfort

7.9

Entertainment

7.9

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

Related info for your journey

Find useful and relevant information for your journey from Porto to Dulles Intl. 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 from for flights from Porto to Washington, D.C. Dulles Intl?

    Porto (OPO), located 6.8 mi from the city center, is the airport you fly out of when you book flights from Porto to Washington, D.C. Dulles Intl. 1 airline have flights from Porto to Washington, D.C. Dulles Intl on a regular basis. Booking flights from Porto to Washington, D.C. Dulles Intl should not be difficult; the airport handles an average of 0 outbound flights to Washington, D.C. Dulles Intl per day.

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

    TAP AIR PORTUGAL, at $500, was found to be the cheapest airline from Porto to Washington, D.C. Dulles Intl Airport.Alternate airlines to your destination round-trip include United Airlines and Lufthansa. TAP AIR PORTUGAL is priced at 25% lower than the current average price of a flight leaving 3 months from now.

  • What are the cheapest airlines to fly from Porto to Washington, D.C. Dulles Intl Airport one-way?

    To fly one-way, consider booking your trip with Royal Air Maroc, which is currently one of the cheapest options available, starting at $511. American Airlines flights start at $550 while deals on Iberia start at $551 one-way.

  • Can I find deals for flights from Porto to Dulles Intl that include hotel bookings?

    Yes. In addition to deals on Porto to Dulles Intl flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Porto to Dulles Intl?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Porto to Dulles Intl.

  • Can I find deals for business class flights from Porto to Dulles Intl?

    Yes. Cheapflights offers flight deals from Porto to Dulles Intl 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 Porto to Washington, D.C. Dulles Intl Airport?

    Currently, August is the cheapest month in which you can book a flight from Porto to Washington, D.C. Dulles Intl Airport (average of $309). Flying from Porto to Washington, D.C. Dulles Intl Airport in July is currently the most expensive (average of $345). 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?

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Alternative routes for Porto to Dulles Intl

See prices for flight routes from nearby airports that may be better suited for you.

Top airline flying from Porto to Dulles Intl

Discover the top airline that operate flights from Porto to Dulles Intl. 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 July 3, 2025.
AirlineCheapestAverageFlexibilityOn-time
TAP AIR PORTUGALCheapest$480Average$751FlexibilityNo cancel feeOn-timeN/A

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