OPO - IAD

$367 Find Cheap Flights from Porto to Washington Dulles Airport

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Porto to Dulles Intl departing on 3/24. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to Washington, D.C. Dulles Intl Airport

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Porto to Washington, D.C., as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Porto to Washington, D.C., as well as popular online travel agencies
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Everything you should know

Cheapest round-trip
$506
TAP AIR PORTUGAL
Fri 1/30Fri 2/6
OPO - IAD • 1 stop
Cheapest one-way
$358
Iberia
Tue 3/24
OPO - IAD • 1 stop
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KAYAK searches 100s of sites at once to find you the best travel deals.
We hope you love your trip to Dulles Intl!
Flight Deals
Booking Insights
Flight Deals

Cheap Flights from Porto to Dulles Intl (OPO-IAD)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Porto to Dulles Intl that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Porto to Dulles Intl

Fri, Jan 30 - Fri, Feb 6
TAP AIR PORTUGAL Logo
2:20 pm - 9:00 pm
OPO
-
IAD
11h 40m1 stop
TAP AIR PORTUGAL Logo
10:30 pm - 5:00 pm
IAD
-
OPO
13h 30m1 stop
$506TAP AIR PORTUGAL
Thu, Jan 15 - Wed, Jan 28
TAP AIR PORTUGAL Logo
7:00 am - 3:15 pm
OPO
-
IAD
13h 15m1 stop
TAP AIR PORTUGAL Logo
10:30 pm - 5:00 pm
IAD
-
OPO
13h 30m1 stop
$508TAP AIR PORTUGAL
Thu, Jan 15 - Wed, Jan 28
Multiple Airlines Logo
6:00 am - 3:46 pm
OPO
-
IAD
38h 46m2 stops
Multiple Airlines Logo
9:45 am - 11:15 am
IAD
-
OPO
20h 30m2 stops
$596Multiple Airlines
Mon, Jan 12 - Mon, Jan 19
KLM Logo
11:15 am - 4:05 pm
OPO
-
IAD
33h 50m1 stop
KLM Logo
6:50 pm - 10:30 am
IAD
-
OPO
10h 40m1 stop
$599KLM
Thu, Jan 15 - Wed, Jan 28
Delta Logo
6:35 am - 4:05 pm
OPO
-
IAD
14h 30m1 stop
Delta Logo
12:23 pm - 10:30 am
IAD
-
OPO
17h 07m2 stops
$600Delta
Thu, Jan 29 - Thu, Feb 5
Delta Logo
5:00 am - 7:09 pm
OPO
-
IAD
19h 09m2 stops
Delta Logo
12:23 pm - 10:25 am
IAD
-
OPO
17h 02m2 stops
$606Delta
Fri, Jan 23 - Sun, Jan 25
United Airlines Logo
12:30 pm - 3:50 pm
OPO
-
IAD
32h 20m1 stop
United Airlines Logo
5:15 pm - 11:40 am
IAD
-
OPO
13h 25m1 stop
$616United Airlines
Fri, Jan 23 - Sun, Jan 25
United Airlines Logo
12:30 pm - 8:26 pm
OPO
-
IAD
36h 56m2 stops
United Airlines Logo
6:00 am - 11:40 am
IAD
-
OPO
24h 40m3 stops
$623United Airlines
Mon, Jan 12 - Mon, Jan 19
KLM Logo
6:30 am - 7:09 pm
OPO
-
IAD
17h 39m2 stops
KLM Logo
7:30 pm - 3:25 pm
IAD
-
OPO
14h 55m2 stops
$678KLM
Thu, Jan 15 - Wed, Jan 28
Multiple Airlines Logo
4:05 pm - 9:00 pm
OPO
-
IAD
33h 55m2 stops
Multiple Airlines Logo
10:30 pm - 11:10 am
IAD
-
OPO
31h 40m3 stops
$739Multiple Airlines
Booking Insights

KAYAK's insights & trends for Porto to Dulles Intl flights

Get data-powered insights and trends into flights from Porto to Dulles Intl to help you find the cheapest flights, the best time to fly and much more.

What’s the cheapest day of the week to fly from Porto to Washington Dulles Airport?

The average price of all round-trip flights from Porto to Washington, D.C. Dulles Intl Airport clicked on KAYAK for each day over the last 12 months.

When flying from Porto to Washington Dulles Airport, you should consider leaving on a Monday and avoid Wednesdays if you are looking for the best rates. For your return to Porto, you’ll find the best rates on Sundays and the most expensive ones on Fridays.

Good to know

Cheapest flight$358
Flight from Porto to Washington Dulles Airport

When to book flights from Porto to Dulles Intl

Are your dates flexible? Find out the best times to travel from Porto to Dulles Intl based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking Porto to Washington Dulles Airport flights

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

    In the last 3 days, the lowest price for a flight from Porto to Washington, D.C. Dulles Intl Airport was $358 for a one-way ticket and $506 for a round-trip.

  • Do I need a passport to fly between Porto and Washington Dulles Airport?

    Yes

  • Which airports will I be using when flying from Porto to Washington Dulles Airport?

    On your way to Washington Dulles Airport, you’ll fly out from Porto. You’ll be landing at Washington, D.C. Dulles Intl.

  • Which aircraft models fly most regularly from Porto to Washington Dulles Airport?

    We unfortunately don’t have that data for this specific route.

  • Which airline alliances offer flights from Porto to Washington Dulles Airport?

    Star Alliance is the only airline alliance operating flights between Porto and Washington Dulles Airport.

  • How does KAYAK find such low prices on flights from Porto to Washington Dulles Airport?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Porto to Washington Dulles Airport.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Porto to Washington Dulles Airport?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Washington Dulles Airport from Porto is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Porto to Washington Dulles Airport?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Washington Dulles Airport with an airline and back to Porto with another airline. Booking your flights between Porto and IAD can sometimes prove cheaper using this method.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Porto to Washington Dulles Airport?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Washington Dulles Airport from Porto up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Reviews of the top airline flying from Porto to Dulles Intl

 
See real verified KAYAK customer reviews for airlines flying from Porto to Washington, D.C.. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Porto to Dulles Intl? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
7.2
TAP AIR PORTUGALOverall score based on 2091 reviews
7.1Comfort
7.0Boarding
6.2Food
7.8Crew
6.3Entertainment
Airline reviews

Flew Business class and did not like anything, flight attendants were rude and not helpful. Food was of poor quality and I did not eat meals.

2.0 MediocreAnonymous, Dec 2025
LIS - LAX
Read more TAP AIR PORTUGAL reviews

Flew Business class and did not like anything, flight attendants were rude and not helpful. Food was of poor quality and I did not eat meals.

Wonderful just hope the had more direct flights to Boston

Boarding process was fast and efficient. Short flight but on time and well organized. I would certainly fly TAP again.

Very long line at the gate, moved slowly. I had expected that boarding a flagship A330neo would be with a jetway directly at the gate, and not a long bus ride to the airplane.

The layover was only one hour and a huge line for passport control. If I didn’t cut the line and argue was every single official, I would’ve spent the night in this one. Obviously.TAP AIR people. do not take into account.this problem with their flight scheduling, which is extremely frustrating. Poor food choices, on the pasta was offered, they ran out of chicken right away. All the sodas and water poured in a tiny 70 mL cups, which is not enough to keep hydrated on the long flight. I had to ask for 34 cups at a time. Flight attendant seemed to be tired and overworked.

Very borderline, low budget airline without low budget prices There are no counts of soda, everything is dispensed enlarged bottles and poured into tiny cups about 70 mL so in order to keep hydrated you have to take 3-4 cups at a time. Also, there was only one food item offered, pasta, they ran out of chicken right away. Snack was very poor. It was called tuna sandwich, which is truly borderline. The flight attend attendance seemed to be overworked and tired.

I am not very tall, and had a difficult time getting my carry-on placed in the overhead bin while passengers were behind me waiting to get to their seats. After struggling with the luggage, I turned it around, and left it, knowing it was not properly placed, but believing there was adequate room for it in the bin. When the flight attendant came through the cabin, she asked whose bag it was, and scolded me for not positioning it correctly. She turned it around and moved on. I thought that her approach was totally unprofessional, calling out a passenger in that manner.

TAP‘s flight attendants seem to be among the least ambitious of all the international flight crews we’ve flown with. . When we left US and went to Portugal, and when we returned from Portugal, flight attendants were not very visible. Then did not offer frequent water breaks and when we had to go back to request water, I was almost an imposition. Meal quality was just average. The dinners were fine. Breakfast wraps were presented soggy.

There was no warning that they have added passport control after check in, the line was enormous and after 46 mins wait we missed our flight. Were forced to leave the airport and purchase new tickets at full price to board a later flight. TAP were unsympathetic and unhelpful.

Boarding we were jammed into a hot crowded bus waiting too long while another bus went in front of us. Appreciated blanket and pillow, movie available helped time pass, the food was not appealing so I had my own snacks, the flight is long, but nothing they can do about that. Staff adequate, flight good.

Everything you need to know for your flight from Porto to Dulles Intl

Information on your arrival and departure airports