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$277+ Cheap flights from Denver (DEN) to Porto (OPO)

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 10/19. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — OPO
Oct 27 — Nov 31
Mon 10/27
Mon 11/3
1 adult, Economy
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Cheapflights Tip: The best prices from Denver Intl to Porto are usually found in January or February, booked 84 days in advance, depart on a Monday or Thursday and return on a Wednesday

Cheap flight deals from Denver to Porto

Discover tips and strategies to find the most affordable flight options for your journey from Denver (DEN) to Porto (OPO). 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 September 27, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$545
(Kiwi.com)

One-way from

$277
(Kiwi.com)

Popular in

June

Cheapest in

January

Average price

$962
Provider with most accurate pricing for Denver Intl-Porto flight deals.
Search Deals
Provider most trusted by Cheapflights users for Denver Intl-Porto flights.
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From Denver Intl to Porto
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One-way flight from Denver Intl to Porto
Search Deals
Highest demand for flights based on searches. 23% potential increase in price ($298 potential increase over avg. RT price).
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Cheapest flight prices on average. 5% potential price decrease ($47 potential savings vs. average RT price).
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Average for round-trip flights in September 2025
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Find flight deals from Denver to Porto

Cheapest flights from Denver to Porto
Explore the most affordable flight options available from Denver to Porto. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 27, 2025.

This Kiwi.com deal was found by Cheapflights users on 9/27. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/276:45 pmDEN - OPO
1 stop14h 10mLufthansa
Wed 11/126:00 amOPO - DEN
1 stop17h 00mLufthansa
Deal found 9/27$545
This Kiwi.com deal was found by Cheapflights users on 9/26. 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 11/44:20 pmDEN - OPO
1 stop13h 30mLufthansa
Tue 11/114:15 pmOPO - DEN
1 stop30h 45mLufthansa
Deal found 9/26$564
This United Airlines deal was found by Cheapflights users on 9/27. 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.
Mon 10/275:00 amDEN - OPO
2 stops22h 30mUnited Airlines
Wed 11/126:00 amOPO - DEN
1 stop17h 00mUnited Airlines
Deal found 9/27$568
This United Airlines deal was found by Cheapflights users on 9/27. 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.
Tue 11/1111:15 amDEN - OPO
2 stops15h 15mUnited Airlines
Tue 11/186:00 amOPO - DEN
1 stop17h 00mUnited Airlines
Deal found 9/27$577
This Cheapflightsfares deal was found by Cheapflights users on 9/26. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/35:45 pmDEN - OPO
1 stop14h 10mLufthansa
Wed 11/126:00 amOPO - DEN
1 stop17h 00mLufthansa
Deal found 9/26$582
This United Airlines deal was found by Cheapflights users on 9/26. 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.
Tue 11/41:45 pmDEN - OPO
1 stop12h 45mUnited Airlines
Tue 11/1112:30 pmOPO - DEN
2 stops28h 25mUnited Airlines
Deal found 9/26$583
This Cheapflightsfares deal was found by Cheapflights users on 9/25. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/286:45 pmDEN - OPO
1 stop14h 00mLufthansa
Fri 11/712:30 pmOPO - DEN
2 stops17h 45mLufthansa
Deal found 9/25$587
This Air France deal was found by Cheapflights users on 9/26. 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 Air France is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/411:26 amDEN - OPO
2 stops16h 04mMultiple Airlines
Tue 11/116:05 amOPO - DEN
2 stops19h 42mMultiple Airlines
Deal found 9/26$591
This Delta deal was found by Cheapflights users on 9/25. 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 10/287:00 amDEN - OPO
2 stops21h 30mDelta
Fri 11/76:30 amOPO - DEN
2 stops23h 34mDelta
Deal found 9/25$592

Cheapflights Fare Finder

 
Customize your flight search to find flights from Denver to Porto 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 September 27, 2025.
Use the filters below to find and compare flights from Denver to Porto that are best for you.

Fly from

Denver

Fly to

Porto

Route

Depart

Return

Price

DenverPorto

DEN - OPO

DENOPO

Denver Intl

Mon 10/27

5:00 am-9:30 am

2 stops22h 30m

Porto

Wed 11/12

6:00 am-4:00 pm

1 stop17h 00m

$568

DenverPorto

DEN - OPO

DENOPO

Denver Intl

Tue 11/11

1:45 pm-9:30 am

1 stop12h 45m

Porto

Tue 11/18

6:00 am-4:00 pm

1 stop17h 00m

$573

DenverPorto

DEN - OPO

DENOPO

Denver Intl

Tue 11/4

1:45 pm-9:30 am

1 stop12h 45m

Porto

Tue 11/11

12:30 pm-9:55 am

2 stops28h 25m

$583

DenverPorto

DEN - OPO

DENOPO

Denver Intl

Tue 10/28

6:45 pm-2:45 pm

1 stop14h 00m

Porto

Fri 11/7

6:15 am-2:35 pm

1 stop15h 20m

$594

DenverPorto

DEN - OPO

DENOPO

Denver Intl

Tue 11/4

9:35 am-9:30 am

2 stops16h 55m

Porto

Tue 11/11

12:30 pm-4:00 pm

1 stop34h 30m

$597

DenverPorto

DEN - OPO

DENOPO

Denver Intl

Mon 11/3

4:47 pm-3:25 pm

2 stops15h 38m

Porto

Wed 11/12

6:00 am-8:38 pm

2 stops21h 38m

$597

DenverPorto

DEN - OPO

DENOPO

Denver Intl

Sun 3/22

6:45 pm-10:25 pm

1 stop21h 40m

Porto

Mon 3/30

4:35 pm-3:35 pm

1 stop30h 00m

$611

DenverPorto

DEN - OPO

DENOPO

Denver Intl

Thu 3/12

8:20 pm-3:10 pm

1 stop36h 50m

Porto

Thu 3/26

4:10 pm-6:35 pm

1 stop32h 25m

$647

DenverPorto

DEN - OPO

DENOPO

Denver Intl

Sat 10/25

8:22 pm-11:00 pm

3 stops44h 38m

$286

DenverPorto

DEN - OPO

DENOPO

Denver Intl

Sun 10/19

4:08 pm-9:00 am

2 stops57h 52m

$301

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/25

Showing 1-10 of 12 results
1
2

Compare providers for flights from Denver to Porto

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Denver to Porto in September.
ProviderPrice AccuracyTrust Score*
FlightHubPrice Accuracy3 starsTrust Score*3 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars
AranGrantPrice Accuracy3 starsTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Denver-Porto flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Denver-Porto flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Denver-Porto flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Denver-Porto 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 Denver-Porto 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 Denver to Porto

Have a flexible travel schedule? Discover the best time to fly to Porto from Denver 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 Denver to Porto

How far ahead should I book a flight from Denver to Porto?

Use this chart to determine the optimal time to book a round-trip flight from Denver to Porto. Price data was last updated on September 19, 2025.

The best time to book flights from Denver to Porto is 84 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.

What is the cheapest month to book a flight from Denver to Porto?

Currently, January is the cheapest month in which you can book a flight from Denver to Porto (average of $523). Flying from Denver to Porto in June is currently the most expensive (average of $1,028). 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 DEN to OPO?

Find hourly flight availability from Denver to Porto. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated September 27, 2025.

It’s optimal to fly from Denver to Porto in the evening. By choosing this option you can save up to 33% on the cost of your flight, compared to a flight at noon.

Reviews of airlines servicing Porto

Get insights into the airlines that provide service to Porto. 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 Porto. Reviews last updated September 27, 2025.
Get a feel of what it's like to fly with United Airlines, Turkish Airlines, and Lufthansa from Denver to Porto by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
United Airlines
7.4
Good
8,926 reviews

Boarding

7.7

Comfort

7.3

Entertainment

7.1

Food

6.6

Overall

7.4

Crew

8.1

Reviews

1 / 20
4.0
Okay

Tim,Sep 2025

IAD - GSP

This was pretty bad. It’s chaos at the Dulles boarding gates for the small regional jets because they use one gate to board 3-4 flights at a time. So, it’s difficult knowing where and when to go. There is little space for any size of carrry-on, so most had to gate check their bags. However, the worst of it was that our single flight attendant fell asleep before we took off and the pilot couldn’t do so until she responded to his messages. My wife had to wake her up! So we were a little late leaving. Not to be thwarted, the flight attendant fell asleep right after take off and there was no sight of her during the flight. When the aircraft touched down, a tray of unsecured canned drinks came crashing onto the aisle up front. I can only assume someone didn’t do what they were supposed to. The pilot was great, but I’m sure he must not be happy with this crew member.
United Airlines
7.4
Good
8,926 reviews
United Airlines
7.4
Good
8,926 reviews

Boarding

7.7

Comfort

7.3

Entertainment

7.1

Food

6.6

Overall

7.4

Crew

8.1

Reviews

1 / 20
4.0
Okay

Tim,Sep 2025

IAD - GSP

This was pretty bad. It’s chaos at the Dulles boarding gates for the small regional jets because they use one gate to board 3-4 flights at a time. So, it’s difficult knowing where and when to go. There is little space for any size of carrry-on, so most had to gate check their bags. However, the worst of it was that our single flight attendant fell asleep before we took off and the pilot couldn’t do so until she responded to his messages. My wife had to wake her up! So we were a little late leaving. Not to be thwarted, the flight attendant fell asleep right after take off and there was no sight of her during the flight. When the aircraft touched down, a tray of unsecured canned drinks came crashing onto the aisle up front. I can only assume someone didn’t do what they were supposed to. The pilot was great, but I’m sure he must not be happy with this crew member.
Turkish Airlines
7.3
Good
3,974 reviews
United Airlines
7.4
Good
8,926 reviews

Boarding

7.7

Comfort

7.3

Entertainment

7.1

Food

6.6

Overall

7.4

Crew

8.1

Reviews

1 / 20
4.0
Okay

Tim,Sep 2025

IAD - GSP

This was pretty bad. It’s chaos at the Dulles boarding gates for the small regional jets because they use one gate to board 3-4 flights at a time. So, it’s difficult knowing where and when to go. There is little space for any size of carrry-on, so most had to gate check their bags. However, the worst of it was that our single flight attendant fell asleep before we took off and the pilot couldn’t do so until she responded to his messages. My wife had to wake her up! So we were a little late leaving. Not to be thwarted, the flight attendant fell asleep right after take off and there was no sight of her during the flight. When the aircraft touched down, a tray of unsecured canned drinks came crashing onto the aisle up front. I can only assume someone didn’t do what they were supposed to. The pilot was great, but I’m sure he must not be happy with this crew member.
Lufthansa
6.8
Okay
7,428 reviews
United Airlines
7.4
Good
8,926 reviews

Boarding

7.7

Comfort

7.3

Entertainment

7.1

Food

6.6

Overall

7.4

Crew

8.1

Reviews

1 / 20
4.0
Okay

Tim,Sep 2025

IAD - GSP

This was pretty bad. It’s chaos at the Dulles boarding gates for the small regional jets because they use one gate to board 3-4 flights at a time. So, it’s difficult knowing where and when to go. There is little space for any size of carrry-on, so most had to gate check their bags. However, the worst of it was that our single flight attendant fell asleep before we took off and the pilot couldn’t do so until she responded to his messages. My wife had to wake her up! So we were a little late leaving. Not to be thwarted, the flight attendant fell asleep right after take off and there was no sight of her during the flight. When the aircraft touched down, a tray of unsecured canned drinks came crashing onto the aisle up front. I can only assume someone didn’t do what they were supposed to. The pilot was great, but I’m sure he must not be happy with this crew member.

Related info for your journey

Find useful and relevant information for your journey from Denver to Porto. 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 Denver to Porto?

    Departing from Denver to Porto will take you 22h 30m. There are 4747 mi between Denver and Porto.

  • What are the cheapest airlines flying from Denver to Porto round-trip?

    Currently priced at $574, Turkish Airlines will fly you from Denver to Porto and back. In addition to Turkish Airlines, many other airlines offer competitively priced options for your trip. Search Cheapflights for deals from Lufthansa and United Airlines - these airlines can fly you to your destination from $663 and $750, respectively. Turkish Airlines is currently priced 40% below the average price you’ll pay for this route.

  • Can I find deals for flights from Denver to Porto that include hotel bookings?

    Yes. In addition to deals on Denver to Porto flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Denver to Porto?

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

  • Can I find deals for business class flights from Denver to Porto?

    Yes. Cheapflights offers flight deals from Denver to Porto 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 Denver to Porto?

    Currently, January is the cheapest month in which you can book a flight from Denver to Porto (average of $523). Flying from Denver to Porto in June is currently the most expensive (average of $1,028). 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 Porto?

Book flights to Porto if you plan to visit one of these locations
Aveiro
Arcos de Valdevez
Coimbra

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Top 3 airlines flying from Denver to Porto

Discover the top 3 airlines that operate flights from Denver to Porto. 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 September 27, 2025.
AirlineCheapestAverageFlexibilityOn-time
Turkish AirlinesCheapest$574Average$679FlexibilityNo cancel feeOn-time77%
LufthansaCheapest$663Average$876FlexibilityNo cancel feeOn-time76%
United AirlinesCheapest$750Average$1,034FlexibilityNo cancel feeOn-time69%

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