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Dulles Intl

$358+ 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 6/1. Fares are subject to change and may not be available on all flights or dates of travel.
OPO — IAD
Mar 24 — Mar 311
Tue 3/24
Tue 3/31
1 adult, Economy
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Cheap 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 February 22, 2026.

This lol.travel deal was found by Cheapflights users on 2/19. 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 lol.travel is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 3/28:00 pm
OPO
-
IAD
1 stop23h 35m
TAP AIR PORTUGAL
Mon 3/166:30 pm
IAD
-
OPO
1 stop11h 30m
TAP AIR PORTUGAL
Deal found 2/19$497
This oojo deal was found by Cheapflights users on 2/21. 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.
Mon 3/98:00 pm
OPO
-
IAD
1 stop23h 35m
TAP AIR PORTUGAL
Mon 3/166:30 pm
IAD
-
OPO
1 stop15h 25m
TAP AIR PORTUGAL
Deal found 2/21$502
This Lufthansa deal was found by Cheapflights users on 2/18. 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.
Mon 5/46:00 am
OPO
-
IAD
1 stop15h 05m
Multiple Airlines
Tue 5/128:20 pm
IAD
-
OPO
1 stop16h 15m
Multiple Airlines
Deal found 2/18$562
This Mytrip deal was found by Cheapflights users on 2/21. 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 3/21:15 pm
OPO
-
IAD
2 stops30h 20m
Multiple Airlines
Mon 3/166:30 pm
IAD
-
OPO
2 stops18h 30m
Multiple Airlines
Deal found 2/21$565
This KLM deal was found by Cheapflights users on 2/21. 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.
Tue 4/76:50 pm
OPO
-
IAD
1 stop25h 45m
KLM
Tue 4/146:15 pm
IAD
-
OPO
1 stop16h 10m
KLM
Deal found 2/21$567
This SWISS deal was found by Cheapflights users on 2/18. 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.
Fri 3/67:20 pm
OPO
-
IAD
1 stop25h 00m
SWISS
Sun 5/248:20 pm
IAD
-
OPO
1 stop30h 35m
SWISS
Deal found 2/18$568
This KLM deal was found by Cheapflights users on 2/20. 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.
Tue 4/2111:30 am
OPO
-
IAD
1 stop33h 05m
KLM
Wed 4/296:15 pm
IAD
-
OPO
1 stop33h 15m
KLM
Deal found 2/20$570

Find 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 February 22, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$502
(oojo)

One-way from

$358
(Kiwi.com)

Popular in

January

Cheapest in

March

Average price

$646
Provider with most accurate pricing for Porto-Washington, D.C. Dulles Intl flight deals.
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Provider most trusted by Cheapflights users for Porto-Washington, D.C. Dulles Intl flights.
Search Deals
From Porto to Washington, D.C. Dulles Intl
Search Deals
One-way flight from Porto to Washington, D.C. Dulles Intl
Search Deals
Highest demand for flights based on searches. 17% potential increase in price ($156 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 6% potential price decrease ($44 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in February 2026
Search Deals

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 February 22, 2026.
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

Mon 5/4

6:00 am-4:05 pm

1 stop15h 05m

Washington, D.C. Dulles Intl

Tue 5/12

8:20 pm-5:35 pm

1 stop16h 15m

$562

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Tue 4/7

6:50 pm-3:35 pm

1 stop25h 45m

Washington, D.C. Dulles Intl

Tue 4/14

6:15 pm-3:25 pm

1 stop16h 10m

$567

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Tue 4/21

6:50 pm-3:35 pm

1 stop25h 45m

Washington, D.C. Dulles Intl

Wed 4/29

6:15 pm-8:30 am

1 stop33h 15m

$570

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Tue 5/5

12:15 pm-4:45 pm

1 stop33h 30m

Washington, D.C. Dulles Intl

Wed 5/13

8:20 pm-7:55 am

1 stop30h 35m

$571

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Mon 3/9

5:00 am-5:05 pm

1 stop16h 05m

Washington, D.C. Dulles Intl

Mon 3/16

1:19 pm-10:30 am

2 stops17h 11m

$576

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Mon 3/9

4:10 pm-5:05 pm

1 stop28h 55m

Washington, D.C. Dulles Intl

Mon 3/16

7:59 pm-3:25 pm

2 stops15h 26m

$582

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Thu 4/16

6:00 am-3:05 pm

1 stop14h 05m

Washington, D.C. Dulles Intl

Sun 4/19

5:41 pm-9:45 am

1 stop11h 04m

$593

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Mon 5/4

6:00 am-4:05 pm

1 stop15h 05m

Washington, D.C. Dulles Intl

Mon 5/11

5:25 pm-12:40 pm

1 stop14h 15m

$594

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Tue 4/21

6:15 am-11:03 pm

2 stops21h 48m

Washington, D.C. Dulles Intl

Wed 4/29

6:15 pm-3:25 pm

1 stop16h 10m

$599

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Sat 6/6

12:15 pm-7:00 pm

1 stop11h 45m

$359

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/19

Showing 1-10 of 21 results
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2
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  • Most accurate provider: When it comes to deals on Porto-Washington, D.C. Dulles Intl Airport flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Porto-Washington, D.C. Dulles Intl Airport flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Porto-Washington, D.C. Dulles Intl Airport flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Porto-Washington, D.C. Dulles Intl Airport 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 Porto-Washington, D.C. Dulles Intl Airport 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 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

How much does it cost to fly round-trip from Porto to Washington, D.C. Dulles Intl Airport?

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 February 22, 2026.
Get a feel of what it's like to fly with TAP AIR PORTUGAL 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.
TAP AIR PORTUGAL
7.1
Good
2,146 reviews

Food

6.2

Crew

7.8

Entertainment

6.3

Overall

7.1

Comfort

7.1

Boarding

7.0

Reviews

1 / 20
8.0
Excellent

Anonymous,Dec 2025

LIS - EWR

Both flights returning to newirk airport was delayed by over a hour with minimum early notification
TAP AIR PORTUGAL
7.1
Good
2,146 reviews
TAP AIR PORTUGAL
7.1
Good
2,146 reviews

Food

6.2

Crew

7.8

Entertainment

6.3

Overall

7.1

Comfort

7.1

Boarding

7.0

Reviews

1 / 20
8.0
Excellent

Anonymous,Dec 2025

LIS - EWR

Both flights returning to newirk airport was delayed by over a hour with minimum early notification

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.

  • How long is the flight from Porto to Washington, D.C. Dulles Intl Airport?

    KLM and SWISS can get you from Porto to Washington, D.C. Dulles Intl Airport in just under 25h 45m. Your travel time can differ by up to 7h 45m. Porto and Washington, D.C. Dulles Intl Airport are separated by a distance of 3537 mi. Both multi-stop and nonstop flights can be found to your destination and back.

  • What is the cheapest airline to fly from Porto to Washington, D.C. Dulles Intl Airport round-trip?

    TAP AIR PORTUGAL, at $492, was found to be the cheapest airline from Porto to Washington, D.C. Dulles Intl Airport.. TAP AIR PORTUGAL is priced at 31% lower than the current average price of a flight leaving 3 months from now.

  • 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.

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
Alexandria
Woodbridge
Tysons
Arlington
Owings Mills
Springfield
Silver Spring
Herndon
Hyattsville
Fredericksburg
Hanover
Laurel
Rockville
Upper Marlboro
Linthicum Heights
Manassas
Bowie
Largo
Clinton
Towson

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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.
Lisbon to Dulles Intl flights
Lisbon to Baltimore flights
Lisbon to Reagan-National flights
Porto to Reagan-National flights
Porto to Baltimore flights

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 February 22, 2026.
AirlineCheapestAverageFlexibilityOn-time
TAP AIR PORTUGALCheapest$492Average$751FlexibilityNo cancel feeOn-timeN/A

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