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Dulles Intl

$382+ Cheap flights from Portugal 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 5/27. Fares are subject to change and may not be available on all flights or dates of travel.
LIS — IAD
May 17 — May 241
Sun 5/17
Sun 5/24
1 adult, Economy
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Cheap flight deals from Portugal to Dulles Intl

Cheapest flights from Portugal to Dulles Intl
Explore the most affordable flight options available from Portugal to Dulles Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on April 17, 2026.

This Lufthansa deal was found by Cheapflights users on 4/13. 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 6/1612:05 pm
OPO
-
IAD
1 stop12h 55m
Multiple Airlines
Tue 6/238:20 pm
IAD
-
OPO
1 stop16h 15m
Multiple Airlines
Deal found 4/13$656
This FlightHub deal was found by Cheapflights users on 4/17. 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.
Thu 10/295:55 pm
LIS
-
IAD
1 stop29h 50m
Royal Air Maroc
Mon 11/28:45 pm
IAD
-
LIS
1 stop15h 10m
Royal Air Maroc
Deal found 4/17$664
This SWISS deal was found by Cheapflights users on 4/14. 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.
Tue 6/168:40 am
OPO
-
IAD
1 stop13h 05m
SWISS
Tue 6/238:20 pm
IAD
-
OPO
1 stop16h 15m
SWISS
Deal found 4/14$664
This Booking.com deal was found by Cheapflights users on 4/13. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/146:00 am
OPO
-
IAD
1 stop14h 05m
Multiple Airlines
Wed 5/278:20 pm
IAD
-
OPO
1 stop17h 10m
Multiple Airlines
Deal found 4/13$665
This SWISS deal was found by Cheapflights users on 4/14. 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.
Thu 5/147:20 pm
OPO
-
IAD
1 stop26h 25m
SWISS
Wed 5/278:20 pm
IAD
-
OPO
1 stop30h 35m
SWISS
Deal found 4/14$666
This Booking.com deal was found by Cheapflights users on 4/12. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/811:40 am
LIS
-
IAD
Nonstop8h 30m
TAP AIR PORTUGAL
Mon 10/55:40 pm
IAD
-
LIS
Nonstop7h 25m
TAP AIR PORTUGAL
Deal found 4/12$669
This Booking.com deal was found by Cheapflights users on 4/15. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/116:00 am
OPO
-
IAD
1 stop14h 05m
Lufthansa
Tue 5/263:25 pm
IAD
-
OPO
1 stop19h 20m
Lufthansa
Deal found 4/15$681
This eDestinos deal was found by Cheapflights users on 4/15. 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 eDestinos is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/308:25 am
LIS
-
IAD
1 stop12h 05m
Multiple Airlines
Mon 8/315:45 pm
IAD
-
LIS
1 stop19h 10m
Multiple Airlines
Deal found 4/15$682
This Royal Air Maroc deal was found by Cheapflights users on 4/12. 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 Royal Air Maroc is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/125:55 pm
LIS
-
IAD
1 stop29h 50m
Royal Air Maroc
Mon 11/168:45 pm
IAD
-
LIS
1 stop9h 50m
Royal Air Maroc
Deal found 4/12$683
This eDestinos deal was found by Cheapflights users on 4/15. 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 eDestinos is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/308:20 am
OPO
-
IAD
1 stop12h 10m
Iberia
Mon 8/315:00 pm
IAD
-
OPO
1 stop18h 00m
Iberia
Deal found 4/15$685
This Kiwi.com deal was found by Cheapflights users on 4/13. 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.
Fri 5/19:15 pm
LIS
-
IAD
1 stop24h 45m
Scandinavian Airlines
Fri 5/298:20 pm
IAD
-
LIS
1 stop20h 45m
Scandinavian Airlines
Deal found 4/13$691
This SWISS deal was found by Cheapflights users on 4/13. 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.
Thu 6/187:20 pm
OPO
-
IAD
2 stops24h 00m
SWISS
Tue 6/238:20 pm
IAD
-
OPO
1 stop16h 15m
SWISS
Deal found 4/13$691

Find flight deals from Portugal to Dulles Intl

Keep the following information in mind while searching for Portugal to Dulles Intl flight deals. Data was last updated April 17, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$656
(Lufthansa)

One-way from

$382
(Kiwi.com)

Popular in

July

Cheapest in

September

Average price

$653

Good round-trip deal

$833 or less

Good one-way deal

$681 or less
Provider with most accurate pricing for Lisbon Humberto Delgado-Washington, D.C. (WAS) flight deals.
Search Deals
Provider most trusted by Cheapflights users for Lisbon Humberto Delgado-Washington, D.C. (WAS) flights.
Search Deals
From Portugal to Washington, D.C. Dulles Intl
Search Deals
One-way flight from Portugal to Washington, D.C. Dulles Intl
Search Deals
Highest demand for flights based on searches. 12% potential increase in price ($96 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($16 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in April 2026
Search Deals
Price to beat on a round-trip flight from Portugal to Washington, D.C. Dulles Intl.
Search Deals
Price to beat on a one-way flight from Portugal to Washington, D.C. Dulles Intl.
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Portugal 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 April 17, 2026.
Use the filters below to find and compare flights from Portugal to Washington, D.C. Dulles Intl Airport that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Thu 6/18

6:00 am-3:55 pm

1 stop14h 55m

Washington, D.C. Dulles Intl

Tue 6/23

8:20 pm-5:35 pm

1 stop16h 15m

$656

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Tue 6/16

8:40 am-4:45 pm

1 stop13h 05m

Washington, D.C. Dulles Intl

Tue 6/23

8:20 pm-5:35 pm

1 stop16h 15m

$664

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Wed 6/17

6:45 pm-2:20 pm

2 stops24h 35m

Washington, D.C. Dulles Intl

Tue 6/23

8:20 pm-5:35 pm

1 stop16h 15m

$692

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Thu 5/14

6:00 am-7:55 pm

1 stop18h 55m

Washington, D.C. Dulles Intl

Wed 5/27

5:42 pm-9:45 am

1 stop11h 03m

$695

PortoWashington, D.C.

OPO - IAD

OPOIAD

Porto

Mon 5/11

6:00 am-4:05 pm

1 stop15h 05m

Washington, D.C. Dulles Intl

Wed 5/27

5:42 pm-9:45 am

1 stop11h 03m

$700

LisbonWashington, D.C.

LIS - IAD

LISIAD

Lisbon Humberto Delgado

Tue 5/5

5:05 am-4:05 pm

1 stop16h 00m

Washington, D.C. Dulles Intl

Sun 5/10

5:25 pm-1:40 pm

1 stop15h 15m

$706

LisbonWashington, D.C.

LIS - IAD

LISIAD

Lisbon Humberto Delgado

Sat 5/16

5:05 am-4:05 pm

1 stop16h 00m

Washington, D.C. Dulles Intl

Wed 6/3

10:20 pm-10:45 pm

1 stop19h 25m

$712

LisbonWashington, D.C.

LIS - IAD

LISIAD

Lisbon Humberto Delgado

Fri 5/1

5:05 am-3:05 pm

1 stop15h 00m

Washington, D.C. Dulles Intl

Sun 5/3

8:20 am-11:05 am

2 stops21h 45m

$713

LisbonWashington, D.C.

LIS - IAD

LISIAD

Lisbon Humberto Delgado

Tue 9/8

6:45 am-7:20 am

2 stops29h 35m

Washington, D.C. Dulles Intl

Mon 10/5

10:10 pm-9:20 am

2 stops30h 10m

$714

LisbonWashington, D.C.

LIS - IAD

LISIAD

Lisbon Humberto Delgado

Wed 5/27

6:45 am-7:19 am

2 stops29h 34m

Washington, D.C. Dulles Intl

Wed 6/3

10:20 pm-10:45 pm

1 stop19h 25m

$714

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/13

Showing 1-10 of 43 resultsSorted by cheapest first
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Best time to book a flight from Portugal to Dulles Intl

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

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

Currently, April is the cheapest month in which you can book a flight from Portugal to Washington, D.C. Dulles Intl Airport (average of $438). Flying from Portugal to Washington, D.C. Dulles Intl Airport in July is currently the most expensive (average of $631). 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 PT to IAD?

Find hourly flight availability from Portugal 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 April 17, 2026.

When flying from Portugal to Washington, D.C. Dulles Intl Airport, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

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

Explore weekly flight availability from Portugal to Dulles Intl. 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 April 17, 2026.

The most flights from PT0 to IAD are scheduled on a Thursday (7 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (3 on average).

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

About 32% of weekly flights between Portugal and Washington, D.C. have experienced delays in the past year, with the average delay time being 132 minutes.

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

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

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

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

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

Over the last year, United Airlines have had the lowest number of delays on this route, with just 28% of flights being delayed.

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 April 17, 2026.
Read through reviews of airlines operating flights from Portugal to Washington, D.C. Dulles Intl Airport, such as United Airlines and TAP AIR PORTUGAL. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
United Airlines
7.4
Good
9,602 reviews

Comfort

7.3

Food

6.6

Entertainment

7.1

Boarding

7.7

Crew

8.1

Overall

7.4

Reviews

1 / 20
8.0
Excellent

Anonymous,Apr 2026

DFW - EWR

The flight was on time. Crew was friendly. Will fly again. The seats was comfortable.
United Airlines
7.4
Good
9,602 reviews
United Airlines
7.4
Good
9,602 reviews

Comfort

7.3

Food

6.6

Entertainment

7.1

Boarding

7.7

Crew

8.1

Overall

7.4

Reviews

1 / 20
8.0
Excellent

Anonymous,Apr 2026

DFW - EWR

The flight was on time. Crew was friendly. Will fly again. The seats was comfortable.
TAP AIR PORTUGAL
7.1
Good
2,207 reviews
United Airlines
7.4
Good
9,602 reviews

Comfort

7.3

Food

6.6

Entertainment

7.1

Boarding

7.7

Crew

8.1

Overall

7.4

Reviews

1 / 20
8.0
Excellent

Anonymous,Apr 2026

DFW - EWR

The flight was on time. Crew was friendly. Will fly again. The seats was comfortable.

Related info for your journey

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

    Airlines like SWISS and United Airlines fly from Portugal to Washington, D.C. Dulles Intl Airport in about 13h 05m. The time it takes to get you to your destination can typically vary by up to 5h 50m. Airlines will cover a distance of 3537 mi. Both multi-stop and nonstop flights can be found to your destination and back.

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

    The cheapest airlines for a one-way flight from Portugal to Washington, D.C. Dulles Intl Airport are Iberia ($353), American Airlines ($358), and TAP AIR PORTUGAL ($365).

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

    Consider Air Canada (67%), United Airlines (67%) or Lufthansa (67%) when booking your flight. These represent the most reliable airlines when flying from Portugal to Washington, D.C. Dulles Intl Airport.

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

    The cheapest flight price from Portugal to Washington, D.C. Dulles Intl Airport is $581. On average you can expect to pay $1,287. The most popular route, (Lisbon Humberto Delgado - Washington, D.C. Dulles Intl), can usually be booked for $699.

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

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

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

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

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

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

    Currently, April is the cheapest month in which you can book a flight from Portugal to Washington, D.C. Dulles Intl Airport (average of $438). Flying from Portugal to Washington, D.C. Dulles Intl Airport in July is currently the most expensive (average of $631). 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
Alexandria
Woodbridge
Tysons
Owings Mills
Springfield
Arlington
Silver Spring
Herndon
Hyattsville
Hanover
Laurel
Rockville
Largo
Upper Marlboro
Waldorf
Bowie
Clinton
Towson
Hunt Valley
Cordova

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Top 2 airlines flying from Portugal to Dulles Intl

Discover the top 2 airlines that operate flights from Portugal 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 April 17, 2026.
AirlineCheapestAverageFlexibilityOn-time
TAP AIR PORTUGALCheapest$492Average$728FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$497Average$789FlexibilityNo cancel feeOn-time69%

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