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$286+ Cheap flights from Dulles Intl (IAD) to Portugal

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 12/1. Fares are subject to change and may not be available on all flights or dates of travel.
IAD — LIS
Nov 29 — Dec 61
Sat 11/29
Sat 12/6
1 adult, Economy
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Find flight deals from Dulles Intl to Portugal

Cheapest flights from Dulles Intl to Portugal
Explore the most affordable flight options available from Dulles Intl to Portugal. Find the lowest fares from popular airlines and budget airlines, with prices last updated on October 30, 2025.

This United Airlines deal was found by Cheapflights users on 10/28. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/195:25 pmIAD - OPO
1 stop12h 50mMultiple Airlines
Tue 12/1612:30 pmOPO - IAD
2 stops15h 51mMultiple Airlines
Deal found 10/28$488
This Delta deal was found by Cheapflights users on 10/27. 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 11/1112:36 pmIAD - OPO
2 stops16h 54mDelta
Tue 11/1811:15 amOPO - IAD
2 stops18h 01mDelta
Deal found 10/27$492
This FlightHub deal was found by Cheapflights users on 10/30. 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.
Wed 12/39:45 amIAD - OPO
2 stops22h 30mAir Canada
Mon 12/86:00 amOPO - IAD
2 stops43h 59mAir Canada
Deal found 10/30$495
This United deal was found by Cheapflights users on 10/28. 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 United is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 11/238:30 amIAD - OPO
2 stops25h 45mMultiple Airlines
Tue 12/96:00 amOPO - IAD
2 stops19h 26mMultiple Airlines
Deal found 10/28$496
This Delta deal was found by Cheapflights users on 10/28. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/1912:11 pmIAD - OPO
2 stops17h 19mDelta
Tue 12/1611:15 amOPO - IAD
2 stops17h 57mDelta
Deal found 10/28$498
This United Airlines deal was found by Cheapflights users on 10/27. 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.
Wed 12/312:50 pmIAD - OPO
2 stops17h 50mUnited Airlines
Wed 12/106:00 amOPO - IAD
2 stops43h 26mUnited Airlines
Deal found 10/27$499
This Priceline deal was found by Cheapflights users on 10/29. 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/39:45 amIAD - OPO
2 stops22h 30mMultiple Airlines
Sun 12/76:15 amOPO - IAD
1 stop18h 50mMultiple Airlines
Deal found 10/29$502
This United Airlines deal was found by Cheapflights users on 10/27. 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.
Wed 12/312:50 pmIAD - OPO
2 stops17h 50mUnited Airlines
Wed 12/176:00 amOPO - IAD
2 stops20h 14mUnited Airlines
Deal found 10/27$503
This United Airlines deal was found by Cheapflights users on 10/29. 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.
Mon 12/2910:33 pmIAD - OPO
2 stops32h 07mUnited Airlines
Fri 1/912:30 pmOPO - IAD
2 stops28h 23mUnited Airlines
Deal found 10/29$504
This Mytrip deal was found by Cheapflights users on 10/29. 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.
Tue 12/29:45 amIAD - OPO
2 stops20h 55mMultiple Airlines
Sun 12/1412:05 pmOPO - IAD
1 stop34h 00mMultiple Airlines
Deal found 10/29$506
This United Airlines deal was found by Cheapflights users on 10/29. 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 11/285:33 pmIAD - OPO
1 stop10h 57mUnited Airlines
Fri 12/512:30 pmOPO - IAD
2 stops23h 57mUnited Airlines
Deal found 10/29$509
This United Airlines deal was found by Cheapflights users on 10/29. 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.
Sun 11/305:33 pmIAD - OPO
1 stop10h 57mUnited Airlines
Sat 12/136:00 amOPO - IAD
2 stops30h 29mUnited Airlines
Deal found 10/29$514

Cheap flight deals from Dulles Intl to Portugal

Keep the following information in mind while searching for Dulles Intl to Portugal flight deals. Data was last updated October 30, 2025.

Most accurate provider

Mytrip
3 stars

Most trusted provider

Mytrip
3 stars

Round-trip from

$492
(CheapOair)

One-way from

$286
(Kiwi.com)

Popular in

December

Cheapest in

February

Average price

$785

Good round-trip deal

$471 or less

Good one-way deal

$289 or less
Provider with most accurate pricing for Washington, D.C. (WAS)-Lisbon Humberto Delgado flight deals.
Search Deals
Provider most trusted by Cheapflights users for Washington, D.C. (WAS)-Lisbon Humberto Delgado flights.
Search Deals
From Washington, D.C. Dulles Intl to Portugal
Search Deals
One-way flight from Washington, D.C. Dulles Intl to Portugal
Search Deals
Highest demand for flights based on searches. 4% potential increase in price ($45 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 October 2025
Search Deals
Price to beat on a round-trip flight from Washington, D.C. Dulles Intl to Portugal.
Search Deals
Price to beat on a one-way flight from Washington, D.C. Dulles Intl to Portugal.
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Dulles Intl to Portugal 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 October 30, 2025.
Use the filters below to find and compare flights from Washington, D.C. Dulles Intl Airport to Portugal that are best for you.

Fly from

Dulles Intl

Fly to

Portugal

Route

Depart

Return

Price

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Tue 11/11

12:36 pm-10:30 am

2 stops16h 54m

Porto

Tue 11/18

11:15 am-12:16 am

2 stops18h 01m

$492

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Wed 12/3

9:45 am-1:15 pm

2 stops22h 30m

Porto

Wed 12/10

12:55 pm-8:59 pm

2 stops37h 04m

$492

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Fri 1/16

10:30 pm-6:00 pm

1 stop14h 30m

Porto

Wed 1/21

10:00 am-9:00 pm

1 stop16h 00m

$499

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Wed 12/3

12:50 pm-11:40 am

2 stops17h 50m

Porto

Wed 12/10

6:00 am-8:26 pm

2 stops43h 26m

$499

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Thu 11/27

5:33 pm-9:30 am

1 stop10h 57m

Porto

Thu 12/4

6:00 am-2:35 pm

1 stop13h 35m

$499

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Wed 12/3

12:50 pm-11:40 am

2 stops17h 50m

Porto

Wed 12/17

6:00 am-9:14 pm

2 stops20h 14m

$503

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Mon 12/29

10:33 pm-11:40 am

2 stops32h 07m

Porto

Fri 1/9

12:30 pm-11:53 am

2 stops28h 23m

$504

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Sun 11/30

5:33 pm-9:30 am

1 stop10h 57m

Porto

Sat 12/13

6:00 am-7:29 am

2 stops30h 29m

$514

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Thu 11/27

1:00 pm-10:30 am

2 stops16h 30m

Porto

Thu 12/4

11:15 am-12:12 am

2 stops17h 57m

$523

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Fri 11/28

1:00 pm-9:30 am

1 stop15h 30m

Porto

Fri 12/5

12:50 pm-4:40 pm

1 stop32h 50m

$526

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/29

Showing 1-10 of 60 results
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Best time to book a flight from Dulles Intl to Portugal

Have a flexible travel schedule? Discover the best time to fly to Portugal 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 Portugal

What is the cheapest month to book a flight from Washington, D.C. Dulles Intl Airport to Portugal?

Currently, July is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to Portugal (average of $346). Flying from Washington, D.C. Dulles Intl Airport to Portugal in December is currently the most expensive (average of $551). 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 PT?

Find hourly flight availability from Dulles Intl to Portugal. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated October 30, 2025.

One of the essential ways to save on airfare from Washington, D.C. Dulles Intl Airport to Portugal is to remain as flexible as possible. Flights that are in the evening tend to be the most expensive. A flight at noon could potentially save you up to 40% on airfare.

What is the cheapest day to fly from Washington, D.C. Dulles Intl Airport to Portugal?

Use this chart to determine the cheapest time to fly round-trip from Dulles Intl to Portugal. Price data was last updated on December 16, 2024.

Travelers seeking maximum savings on their Washington, D.C. Dulles Intl Airport to Portugal flight should consider departing on Tuesday at noon when fares are most often at their lowest. Friday at noon flights should be avoided if possible as fares are typically the most expensive at this time.

Reviews of airlines servicing Portugal

Get insights into the airlines that provide service to Portugal. 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 Portugal. Reviews last updated October 30, 2025.
See what other customers who have flown with United Airlines, Aer Lingus, and TAP AIR PORTUGAL from Washington, D.C. Dulles Intl Airport to Portugal have to say. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
United Airlines
7.4
Good
8,998 reviews

Comfort

7.3

Entertainment

7.1

Crew

8.1

Overall

7.4

Boarding

7.7

Food

6.6

Reviews

1 / 20
2.0
Mediocre

Sebrena,Oct 2025

IAH - RSW

The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000
United Airlines
7.4
Good
8,998 reviews
United Airlines
7.4
Good
8,998 reviews

Comfort

7.3

Entertainment

7.1

Crew

8.1

Overall

7.4

Boarding

7.7

Food

6.6

Reviews

1 / 20
2.0
Mediocre

Sebrena,Oct 2025

IAH - RSW

The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000
Aer Lingus
7.2
Good
1,365 reviews
United Airlines
7.4
Good
8,998 reviews

Comfort

7.3

Entertainment

7.1

Crew

8.1

Overall

7.4

Boarding

7.7

Food

6.6

Reviews

1 / 20
2.0
Mediocre

Sebrena,Oct 2025

IAH - RSW

The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000
TAP AIR PORTUGAL
7.1
Good
2,040 reviews
United Airlines
7.4
Good
8,998 reviews

Comfort

7.3

Entertainment

7.1

Crew

8.1

Overall

7.4

Boarding

7.7

Food

6.6

Reviews

1 / 20
2.0
Mediocre

Sebrena,Oct 2025

IAH - RSW

The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000
Lufthansa
6.8
Okay
7,541 reviews
United Airlines
7.4
Good
8,998 reviews

Comfort

7.3

Entertainment

7.1

Crew

8.1

Overall

7.4

Boarding

7.7

Food

6.6

Reviews

1 / 20
2.0
Mediocre

Sebrena,Oct 2025

IAH - RSW

The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000
Royal Air Maroc
6.2
Okay
525 reviews
United Airlines
7.4
Good
8,998 reviews

Comfort

7.3

Entertainment

7.1

Crew

8.1

Overall

7.4

Boarding

7.7

Food

6.6

Reviews

1 / 20
2.0
Mediocre

Sebrena,Oct 2025

IAH - RSW

The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000

Related info for your journey

Find useful and relevant information for your journey from Dulles Intl to Portugal. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

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

    Delta, TAP AIR PORTUGAL, and United Airlines can get you from Washington, D.C. Dulles Intl Airport to Portugal in just under 14h 30m. Your travel time can differ by up to 3h 20m. The distance between Washington, D.C. Dulles Intl Airport and Portugal is about 3537 mi. This flight may include one or multiple stops.

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

    The cheapest airlines for a one-way flight from Washington, D.C. Dulles Intl Airport to Portugal are Royal Air Maroc ($364), Air Canada ($377), and Scandinavian Airlines ($402).

  • What are the most popular routes from Washington, D.C. Dulles Intl Airport to Portugal?

    While some choose either Washington, D.C. Dulles Intl - Porto or Washington, D.C. Dulles Intl - Funchal Madeira, Washington, D.C. Dulles Intl - Lisbon Humberto Delgado is the most popular route from Washington, D.C. Dulles Intl Airport to Portugal.

  • What are the most reliable airlines from Washington, D.C. Dulles Intl Airport to Portugal?

    The top 3 most reliable airlines when flying from Washington, D.C. Dulles Intl Airport to Portugal are JetBlue (81%), TAP AIR PORTUGAL (81%) and Air Canada (73%).

  • What are the cheapest flights from Washington, D.C. Dulles Intl Airport to Portugal?

    Looking for the cheapest flight from Washington, D.C. Dulles Intl Airport to Portugal? While on average our users pay $1,308, our data indicates the cheapest price to be $202. The most popular route (Washington, D.C. Dulles Intl - Lisbon Humberto Delgado), is priced around $440.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Dulles Intl to Portugal 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 Portugal?

    Currently, July is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to Portugal (average of $346). Flying from Washington, D.C. Dulles Intl Airport to Portugal in December is currently the most expensive (average of $551). 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

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Alternative routes for Dulles Intl to Portugal

See prices for flight routes from nearby airports that may be better suited for you.
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Dulles Intl to Munich flights
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Reagan-National to Leonardo da Vinci/Fiumicino flights
Baltimore to Leonardo da Vinci/Fiumicino flights
Dulles Intl to Keflavik Intl flights
Dulles Intl to Zurich flights
Baltimore to Lisbon flights
Baltimore to Luton flights
Reagan-National to Barcelona-El Prat flights
Reagan-National to Lisbon flights
Baltimore to Keflavik Intl flights
Reagan-National to Frankfurt flights
Dulles Intl to Edinburgh flights
Baltimore to Frankfurt flights
Baltimore to Barcelona-El Prat flights
Reagan-National to Dublin flights
Dulles Intl to Geneva flights
Reagan-National to Keflavik Intl flights
Dulles Intl to Beauvais-Tille flights
Baltimore to Dublin flights
Dulles Intl to Malpensa flights
Baltimore to London City flights
Dulles Intl to Bruxelles-National flights

Top 10 airlines flying from Dulles Intl to Portugal

Discover the top 10 airlines that operate flights from Dulles Intl to Portugal. 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 October 30, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$493Average$975FlexibilityNo cancel feeOn-time69%
Scandinavian AirlinesCheapest$504Average$599FlexibilityNo cancel feeOn-time77%
TAP AIR PORTUGALCheapest$506Average$905FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$508Average$646FlexibilityNo cancel feeOn-time71%
British AirwaysCheapest$510Average$692FlexibilityNo cancel feeOn-time70%
IberiaCheapest$515Average$721FlexibilityNo cancel feeOn-time77%
DeltaCheapest$533Average$846FlexibilityNo cancel feeOn-timeN/A
Royal Air MarocCheapest$552Average$673FlexibilityNo cancel feeOn-time75%
KLMCheapest$555Average$741FlexibilityNo cancel feeOn-time75%
Turkish AirlinesCheapest$586Average$670FlexibilityNo cancel feeOn-time77%

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