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$276+ 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 2/1. Fares are subject to change and may not be available on all flights or dates of travel.
IAD — LIS
Jan 17 — Jan 241
Sat 1/17
Sat 1/24
1 adult, Economy
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Cheap 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 December 18, 2025.

This oojo deal was found by Cheapflights users on 12/17. 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 12/3110:30 pmIAD - LIS
Nonstop7h 05mTAP AIR PORTUGAL
Sat 1/109:00 pmLIS - IAD
2 stops39h 20mTAP AIR PORTUGAL
Deal found 12/17$843
This Kiwi.com deal was found by Cheapflights users on 12/16. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/318:45 pmIAD - LIS
1 stop9h 50mMultiple Airlines
Thu 1/85:55 amLIS - IAD
2 stops31h 00mMultiple Airlines
Deal found 12/16$992
This Kiwi.com deal was found by Cheapflights users on 12/16. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/3110:30 pmIAD - LIS
Nonstop7h 05mTAP AIR PORTUGAL
Thu 1/89:00 pmLIS - IAD
2 stops39h 20mTAP AIR PORTUGAL
Deal found 12/16$1,015
This FlightHub deal was found by Cheapflights users on 12/17. 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 12/245:15 pmIAD - LIS
2 stops18h 50mTAP AIR PORTUGAL
Mon 12/2911:25 amLIS - IAD
Nonstop8h 50mTAP AIR PORTUGAL
Deal found 12/17$1,105
This Mytrip deal was found by Cheapflights users on 12/16. 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 12/168:30 pmIAD - OPO
3 stops30h 30mMultiple Airlines
Sun 12/216:30 amOPO - IAD
2 stops17h 15mMultiple Airlines
Deal found 12/16$1,117
This Icelandair deal was found by Cheapflights users on 12/17. 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 Icelandair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/307:40 pmIAD - LIS
2 stops15h 45mIcelandair
Thu 1/84:05 pmLIS - IAD
2 stops31h 25mIcelandair
Deal found 12/17$1,127
This Kiwi.com deal was found by Cheapflights users on 12/17. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/2810:55 pmIAD - LIS
2 stops17h 20mMultiple Airlines
Tue 12/3010:45 amLIS - IAD
Nonstop8h 50mMultiple Airlines
Deal found 12/17$1,138
This Gurufare deal was found by Cheapflights users on 12/17. 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.
Tue 12/307:40 pmIAD - LIS
2 stops21h 10mMultiple Airlines
Thu 1/89:20 pmLIS - IAD
1 stop26h 10mMultiple Airlines
Deal found 12/17$1,147
This Kiwi.com deal was found by Cheapflights users on 12/16. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/305:30 pmIAD - LIS
Nonstop7h 05mTAP AIR PORTUGAL
Tue 1/69:00 pmLIS - IAD
2 stops39h 20mTAP AIR PORTUGAL
Deal found 12/16$1,150
This KAYAK deal was found by Cheapflights users on 12/16. 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 KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/317:40 pmIAD - LIS
2 stops21h 30mIcelandair
Wed 1/77:05 amLIS - IAD
2 stops40h 25mIcelandair
Deal found 12/16$1,170
This Kiwi.com deal was found by Cheapflights users on 12/17. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/285:05 pmIAD - FNC
1 stop25h 15mMultiple Airlines
Sat 1/1011:55 pmFNC - IAD
2 stops26h 05mMultiple Airlines
Deal found 12/17$1,264
This Travelocity deal was found by Cheapflights users on 12/17. 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 Travelocity is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/2410:05 pmIAD - OPO
1 stop18h 55mMultiple Airlines
Sun 12/2812:00 pmOPO - IAD
1 stop14h 00mMultiple Airlines
Deal found 12/17$1,265

Find 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 December 18, 2025.

Most accurate provider

Mytrip
3 stars

Most trusted provider

Mytrip
3 stars

Round-trip from

$436
(Kiwi.com)

One-way from

$276
(Kiwi.com)

Popular in

December

Cheapest in

February

Average price

$1,391

Good round-trip deal

$547 or less

Good one-way deal

$323 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. 5% potential increase in price ($48 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 4% potential price decrease ($43 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in December 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 December 18, 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

Wed 2/11

6:50 pm-10:30 am

1 stop10h 40m

Porto

Tue 2/17

5:00 am-4:05 pm

1 stop16h 05m

$478

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Sun 1/11

6:50 pm-10:30 am

1 stop10h 40m

Porto

Thu 1/22

5:00 am-4:05 pm

1 stop16h 05m

$478

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Wed 3/18

7:50 pm-10:30 am

1 stop10h 40m

Porto

Wed 3/25

5:00 am-5:05 pm

1 stop16h 05m

$478

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Sun 2/15

6:50 pm-10:30 am

1 stop10h 40m

Porto

Wed 2/25

11:15 am-4:05 pm

1 stop33h 50m

$478

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Mon 1/12

5:25 pm-11:15 am

1 stop12h 50m

Porto

Tue 1/20

12:05 pm-3:10 pm

1 stop32h 05m

$482

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Sun 1/11

12:23 pm-10:30 am

2 stops17h 07m

Porto

Tue 1/20

5:00 am-4:05 pm

1 stop16h 05m

$483

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Sun 2/15

12:38 pm-10:30 am

2 stops16h 52m

Porto

Wed 2/25

5:00 am-4:05 pm

1 stop16h 05m

$483

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Tue 1/13

12:29 pm-10:30 am

2 stops17h 01m

Porto

Tue 1/20

5:00 am-4:05 pm

1 stop16h 05m

$483

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Tue 3/24

1:19 pm-10:30 am

2 stops17h 11m

Porto

Tue 3/31

5:00 am-3:35 pm

1 stop15h 35m

$483

Washington, D.C.Porto

IAD - OPO

IADOPO

Washington, D.C. Dulles Intl

Mon 1/12

7:49 pm-10:30 am

2 stops33h 41m

Porto

Wed 1/21

11:15 am-4:05 pm

1 stop33h 50m

$488

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/16

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 $345). Flying from Washington, D.C. Dulles Intl Airport to Portugal in September is currently the most expensive (average of $529). 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 December 18, 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.

Weekly flight availability from Washington, D.C. Dulles Intl Airport to Portugal

Explore weekly flight availability from Dulles Intl to Portugal. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated December 18, 2025.

The most flights from IAD to PT0 are scheduled on a Monday (5 on average). You will have fewer flight options on Monday, which is when the least amount of flights are scheduled (5 on average).

How often are flights from Washington, D.C. to Portugal delayed?

About 28% of weekly flights between Washington, D.C. and Portugal have experienced delays in the past year, with the average delay time being 140 minutes.

What is the most punctual flight time for Washington, D.C. to Portugal flights?

Historically, flights departing in the evening are less likely to be delayed, whereas flights leaving in the morning tend to experience delays more often.

What day of the week experiences the fewest flight delays on this route?

Tuesday tends to have the lowest number of delays on this route, whereas Friday has historically faced a higher average of delays compared to other days of the week.

Which airline has the best punctuality record on Washington, D.C. to Portugal flights?

Over the last year, TAP AIR PORTUGAL have had the lowest number of delays on this route, with just 26% of flights being delayed.

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 December 18, 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
9,095 reviews

Food

6.6

Entertainment

7.1

Comfort

7.3

Crew

8.1

Overall

7.4

Boarding

7.7

Reviews

1 / 20
4.0
Okay

Kevin,Dec 2025

BOS - EWR

Seems like every United flight has a delay and it’s always someone else’s fault. Step up and take some accountability
United Airlines
7.4
Good
9,095 reviews
United Airlines
7.4
Good
9,095 reviews

Food

6.6

Entertainment

7.1

Comfort

7.3

Crew

8.1

Overall

7.4

Boarding

7.7

Reviews

1 / 20
4.0
Okay

Kevin,Dec 2025

BOS - EWR

Seems like every United flight has a delay and it’s always someone else’s fault. Step up and take some accountability
Aer Lingus
7.2
Good
1,399 reviews
United Airlines
7.4
Good
9,095 reviews

Food

6.6

Entertainment

7.1

Comfort

7.3

Crew

8.1

Overall

7.4

Boarding

7.7

Reviews

1 / 20
4.0
Okay

Kevin,Dec 2025

BOS - EWR

Seems like every United flight has a delay and it’s always someone else’s fault. Step up and take some accountability
TAP AIR PORTUGAL
7.2
Good
2,092 reviews
United Airlines
7.4
Good
9,095 reviews

Food

6.6

Entertainment

7.1

Comfort

7.3

Crew

8.1

Overall

7.4

Boarding

7.7

Reviews

1 / 20
4.0
Okay

Kevin,Dec 2025

BOS - EWR

Seems like every United flight has a delay and it’s always someone else’s fault. Step up and take some accountability
Lufthansa
6.8
Okay
7,637 reviews
United Airlines
7.4
Good
9,095 reviews

Food

6.6

Entertainment

7.1

Comfort

7.3

Crew

8.1

Overall

7.4

Boarding

7.7

Reviews

1 / 20
4.0
Okay

Kevin,Dec 2025

BOS - EWR

Seems like every United flight has a delay and it’s always someone else’s fault. Step up and take some accountability
Royal Air Maroc
6.2
Okay
539 reviews
United Airlines
7.4
Good
9,095 reviews

Food

6.6

Entertainment

7.1

Comfort

7.3

Crew

8.1

Overall

7.4

Boarding

7.7

Reviews

1 / 20
4.0
Okay

Kevin,Dec 2025

BOS - EWR

Seems like every United flight has a delay and it’s always someone else’s fault. Step up and take some accountability

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?

    KLM, Delta, and SWISS can get you from Washington, D.C. Dulles Intl Airport to Portugal in just under 10h 40m. Your travel time can differ by up to 2h 10m. 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 TAP AIR PORTUGAL ($253), Royal Air Maroc ($353), and Scandinavian Airlines ($358).

  • 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 Air Canada (78%), United Airlines (78%) and Lufthansa (78%).

  • 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 $1,571, our data indicates the cheapest price to be $267. The most popular route (Washington, D.C. Dulles Intl - Lisbon Humberto Delgado), is priced around $490.

  • 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 $345). Flying from Washington, D.C. Dulles Intl Airport to Portugal in September is currently the most expensive (average of $529). 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.
Dulles Intl to Heathrow flights
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Reagan-National to Charles de Gaulle flights
Dulles Intl to Frankfurt flights
Baltimore to Leonardo da Vinci/Fiumicino flights
Reagan-National to Orly flights
Reagan-National to Leonardo da Vinci/Fiumicino flights
Reagan-National to Istanbul flights
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Reagan-National to Madrid flights
Baltimore to Madrid flights
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Baltimore to Barcelona-El Prat flights
Baltimore to Istanbul flights
Dulles Intl to Bruxelles-National flights
Reagan-National to Lisbon flights
Reagan-National to Barcelona-El Prat flights
Baltimore to Lisbon flights
Dulles Intl to Sabiha Gokcen flights
Dulles Intl to Vienna flights
Baltimore to Keflavik Intl flights
Baltimore to Athens flights
Dulles Intl to Malpensa flights
Baltimore to Dublin flights
Reagan-National to Dublin flights
Reagan-National to Athens flights
Dulles Intl to Geneva flights
Baltimore to Amsterdam flights
Reagan-National to Keflavik Intl flights
Dulles Intl to Copenhagen flights
Dulles Intl to Vicenza 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 December 18, 2025.
AirlineCheapestAverageFlexibilityOn-time
DeltaCheapest$439Average$821FlexibilityNo cancel feeOn-timeN/A
SWISSCheapest$444Average$681FlexibilityNo cancel feeOn-time79%
United AirlinesCheapest$493Average$967FlexibilityNo cancel feeOn-time69%
Scandinavian AirlinesCheapest$504Average$599FlexibilityNo cancel feeOn-time77%
TAP AIR PORTUGALCheapest$504Average$893FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$508Average$646FlexibilityNo cancel feeOn-time71%
British AirwaysCheapest$510Average$674FlexibilityNo cancel feeOn-time70%
IberiaCheapest$515Average$721FlexibilityNo cancel feeOn-time77%
Royal Air MarocCheapest$551Average$669FlexibilityNo cancel feeOn-time75%
KLMCheapest$555Average$741FlexibilityNo cancel feeOn-time75%

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