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$254+ Cheap flights from Key Largo, FL 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 7/13. Fares are subject to change and may not be available on all flights or dates of travel.
MIA — OPO
May 4 — May 111
Sun 5/4
Sun 5/11
1 adult, Economy
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Cheapflights Tip: The best prices from Key Largo to Porto are usually found in February or January, booked 73 days in advance, depart on a Tuesday or Wednesday and return on a Thursday

Cheap flight deals from Key Largo to Porto

Keep the following information in mind while searching for Key Largo to Porto flight deals. Data was last updated April 29, 2025.

Most accurate provider

AranGrant
3 stars

Most trusted provider

AranGrant
3 stars

Round-trip from

$616
(Air Canada)

One-way from

$254
(oojo)

Popular in

June

Cheapest in

February

Average price

$698
Provider with most accurate pricing for Miami-Porto flight deals.
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Provider most trusted by Cheapflights users for Miami-Porto flights.
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From Key Largo to Porto
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One-way flight from Key Largo to Porto
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Highest demand for flights based on searches. 19% potential increase in price ($172 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($20 potential savings vs. average RT price).
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Average for round-trip flights in April 2025
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Find flight deals from Key Largo to Porto

Cheapest flights from Key Largo to Porto
Explore the most affordable flight options available from Key Largo to Porto. Find the lowest fares from popular airlines and budget airlines, with prices last updated on April 29, 2025.

This Air Canada deal was found by Cheapflights users on 4/29. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/242:20 pmMIA - OPO
1 stop14h 00mMultiple Airlines
Fri 10/37:20 pmOPO - MIA
2 stops30h 28mMultiple Airlines
Deal found 4/29$616
This Orbitz deal was found by Cheapflights users on 4/29. 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 Orbitz is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/1011:55 amMIA - OPO
2 stops14h 40mIberia
Fri 9/198:15 amOPO - MIA
1 stop16h 40mIberia
Deal found 4/29$627
This American Airlines deal was found by Cheapflights users on 4/29. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/84:55 pmMIA - OPO
1 stop13h 45mAmerican Airlines
Wed 10/158:15 amOPO - MIA
2 stops18h 35mAmerican Airlines
Deal found 4/29$630
This Air Canada deal was found by Cheapflights users on 4/29. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/82:20 pmMIA - OPO
1 stop14h 15mAir Canada
Tue 9/1612:50 pmOPO - MIA
2 stops38h 58mAir Canada
Deal found 4/29$644
This Delta deal was found by Cheapflights users on 4/29. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/1510:50 pmMIA - OPO
1 stop28h 35mDelta
Wed 7/236:15 amOPO - MIA
2 stops20h 10mDelta
Deal found 4/29$646
This United Airlines deal was found by Cheapflights users on 4/29. 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.
Tue 9/91:25 pmMIA - OPO
1 stop13h 20mUnited Airlines
Mon 9/229:00 amOPO - MIA
1 stop13h 10mUnited Airlines
Deal found 4/29$672
This SWISS deal was found by Cheapflights users on 4/29. 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 SWISS is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/77:40 pmMIA - OPO
1 stop17h 35mSWISS
Fri 9/197:20 pmOPO - MIA
1 stop27h 10mSWISS
Deal found 4/29$681
This oojo deal was found by Cheapflights users on 4/29. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/512:25 amMIA - OPO
1 stop17h 10mTAP AIR PORTUGAL
Wed 9/1711:00 amOPO - MIA
1 stop15h 50mTAP AIR PORTUGAL
Deal found 4/29$682
This Gurufare deal was found by Cheapflights users on 4/29. 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 Gurufare is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/19:30 pmMIA - OPO
1 stop16h 50mAir Europa
Sat 9/611:35 amOPO - MIA
1 stop12h 10mAir Europa
Deal found 4/29$713
This Lufthansa deal was found by Cheapflights users on 4/29. 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 Lufthansa is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/84:40 pmMIA - OPO
2 stops25h 40mLufthansa
Fri 9/196:15 amOPO - MIA
2 stops42h 11mLufthansa
Deal found 4/29$728
This British Airways deal was found by Cheapflights users on 4/29. 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 British Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/15:00 pmMIA - OPO
1 stop21h 30mBritish Airways
Mon 7/149:10 pmOPO - MIA
1 stop22h 15mBritish Airways
Deal found 4/29$751

Cheapflights Fare Finder

Customize your flight search to find flights from Key Largo 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 April 29, 2025.
Use the filters below to find and compare flights from Key Largo to Porto that are best for you.

Fly from

Key Largo

Fly to

Porto

Route

Depart

Return

Price

MiamiPorto

MIA - OPO

MIAOPO

Miami

Wed 9/24

2:20 pm-9:20 am

1 stop14h 00m

Porto

Fri 10/3

7:20 pm-8:48 pm

2 stops30h 28m

$616

MiamiPorto

MIA - OPO

MIAOPO

Miami

Wed 9/10

11:55 am-7:35 am

2 stops14h 40m

Porto

Fri 9/19

8:15 am-7:55 pm

1 stop16h 40m

$627

MiamiPorto

MIA - OPO

MIAOPO

Miami

Wed 10/8

4:55 pm-11:40 am

1 stop13h 45m

Porto

Wed 10/15

8:15 am-9:50 pm

2 stops18h 35m

$630

MiamiPorto

MIA - OPO

MIAOPO

Miami

Mon 9/8

2:20 pm-9:35 am

1 stop14h 15m

Porto

Tue 9/16

12:50 pm-10:48 pm

2 stops38h 58m

$644

MiamiPorto

MIA - OPO

MIAOPO

Miami

Tue 7/15

10:50 pm-8:25 am

1 stop28h 35m

Porto

Wed 7/23

6:15 am-9:25 pm

2 stops20h 10m

$646

MiamiPorto

MIA - OPO

MIAOPO

Miami

Tue 9/9

1:25 pm-7:45 am

1 stop13h 20m

Porto

Mon 9/22

9:00 am-5:10 pm

1 stop13h 10m

$672

MiamiPorto

MIA - OPO

MIAOPO

Miami

Sun 9/7

7:40 pm-6:15 pm

1 stop17h 35m

Porto

Fri 9/19

7:20 pm-5:30 pm

1 stop27h 10m

$681

MiamiPorto

MIA - OPO

MIAOPO

Miami

Fri 9/5

12:25 am-10:35 pm

1 stop17h 10m

Porto

Wed 9/17

11:00 am-9:50 pm

1 stop15h 50m

$682

MiamiPorto

MIA - OPO

MIAOPO

Miami

Mon 9/1

9:30 pm-7:20 pm

1 stop16h 50m

Porto

Thu 9/4

7:35 am-6:45 pm

1 stop16h 10m

$713

MiamiPorto

MIA - OPO

MIAOPO

Miami

Mon 9/8

4:40 pm-11:20 pm

2 stops25h 40m

Porto

Fri 9/19

6:15 am-7:26 pm

2 stops42h 11m

$728

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/29

Showing 1-10 of 20 results
1
2

Best time to book a flight from Key Largo to Porto

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

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

Use this chart to determine the optimal time to book a round-trip flight from Key Largo to Porto. Price data was last updated on April 25, 2025.

The price you pay for your flight from Key Largo to Porto may vary depending on when you book. For the best chance of a lower fare, look to book 73 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.

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

Currently, January is the cheapest month in which you can book a flight from Key Largo to Porto (average of $523). Flying from Key Largo to Porto in June is currently the most expensive (average of $1,071). 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 KE9 to OPO?

Find hourly flight availability from Key Largo 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 April 29, 2025.

When flying from Key Largo to Porto, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

What is the cheapest day to fly from Key Largo to Porto?

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

Travelers seeking maximum savings on their Key Largo to Porto flight should consider departing on Tuesday afternoons when fares are most often at their lowest. Sunday afternoons flights should be avoided if possible as fares are typically the most expensive at this time.

Rainfall in Porto by month

Plan your trip to Porto by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Porto ranges from 0.7 - 7.7 inches per month. December is typically the wettest month, when rainfall can reach 7.7 in. July is typically the driest time to visit Porto when rainfall is around 0.7 in.

Temperature in Porto by month

Plan your trip to Porto by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Porto, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 68.0 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 48.2 F).

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 April 29, 2025.
Read through reviews of airlines operating flights from Key Largo to Porto, such as Delta, SWISS and United Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Delta
8.0
Very good
7,936 reviews

Entertainment

7.9

Boarding

8.2

Food

7.3

Crew

8.5

Overall

8.0

Comfort

7.9

Reviews

1 / 20
2.0
Mediocre

Santiago,Apr 2024

MCO - ATL

When I was going to board, one of the staff members told me that I could not board with my passport bag because it was tree items and I would need to check a bag. This was so stupid ! The bag was small. So I had to put my things in my pockets, put the funny bag inside the other bag. Then go throw it. Then in the plane put everything back again in my funny bag.
Delta
8.0
Very good
7,936 reviews
Delta
8.0
Very good
7,936 reviews

Entertainment

7.9

Boarding

8.2

Food

7.3

Crew

8.5

Overall

8.0

Comfort

7.9

Reviews

1 / 20
2.0
Mediocre

Santiago,Apr 2024

MCO - ATL

When I was going to board, one of the staff members told me that I could not board with my passport bag because it was tree items and I would need to check a bag. This was so stupid ! The bag was small. So I had to put my things in my pockets, put the funny bag inside the other bag. Then go throw it. Then in the plane put everything back again in my funny bag.
SWISS
7.5
Good
1,588 reviews
Delta
8.0
Very good
7,936 reviews

Entertainment

7.9

Boarding

8.2

Food

7.3

Crew

8.5

Overall

8.0

Comfort

7.9

Reviews

1 / 20
2.0
Mediocre

Santiago,Apr 2024

MCO - ATL

When I was going to board, one of the staff members told me that I could not board with my passport bag because it was tree items and I would need to check a bag. This was so stupid ! The bag was small. So I had to put my things in my pockets, put the funny bag inside the other bag. Then go throw it. Then in the plane put everything back again in my funny bag.
United Airlines
7.4
Good
8,696 reviews
Delta
8.0
Very good
7,936 reviews

Entertainment

7.9

Boarding

8.2

Food

7.3

Crew

8.5

Overall

8.0

Comfort

7.9

Reviews

1 / 20
2.0
Mediocre

Santiago,Apr 2024

MCO - ATL

When I was going to board, one of the staff members told me that I could not board with my passport bag because it was tree items and I would need to check a bag. This was so stupid ! The bag was small. So I had to put my things in my pockets, put the funny bag inside the other bag. Then go throw it. Then in the plane put everything back again in my funny bag.
Turkish Airlines
7.3
Good
3,788 reviews
Delta
8.0
Very good
7,936 reviews

Entertainment

7.9

Boarding

8.2

Food

7.3

Crew

8.5

Overall

8.0

Comfort

7.9

Reviews

1 / 20
2.0
Mediocre

Santiago,Apr 2024

MCO - ATL

When I was going to board, one of the staff members told me that I could not board with my passport bag because it was tree items and I would need to check a bag. This was so stupid ! The bag was small. So I had to put my things in my pockets, put the funny bag inside the other bag. Then go throw it. Then in the plane put everything back again in my funny bag.
American Airlines
7.2
Good
10,000 reviews
Delta
8.0
Very good
7,936 reviews

Entertainment

7.9

Boarding

8.2

Food

7.3

Crew

8.5

Overall

8.0

Comfort

7.9

Reviews

1 / 20
2.0
Mediocre

Santiago,Apr 2024

MCO - ATL

When I was going to board, one of the staff members told me that I could not board with my passport bag because it was tree items and I would need to check a bag. This was so stupid ! The bag was small. So I had to put my things in my pockets, put the funny bag inside the other bag. Then go throw it. Then in the plane put everything back again in my funny bag.

Related info for your journey

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

  • What airport do you fly into for flights to Porto from Key Largo?

    If you book a flight to Porto from Key Largo, you will be flying to Porto, which is the city’s only airport. Porto (OPO) is located 6.8 mi from the center of Porto. There are 0 flights from Key Largo to Porto per day from 11 different airlines.

  • What are the cheapest airlines to fly from Key Largo to Porto one-way?

    The cheapest airline one-way is TAP AIR PORTUGAL, with whom users have recently found tickets for as low as $254. However, be on the lookout for offers from Air Europa and Delta, as they are both options that can get you from Key Largo to Porto for a low price.

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

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

  • How can I find direct flights from Key Largo to Porto?

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

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

    Yes. Cheapflights offers flight deals from Key Largo 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 Key Largo to Porto?

    Currently, January is the cheapest month in which you can book a flight from Key Largo to Porto (average of $523). Flying from Key Largo to Porto in June is currently the most expensive (average of $1,071). 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 Key Largo?

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

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Top 10 airlines flying from Key Largo to Porto

Discover the top 10 airlines that operate flights from Key Largo 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 April 29, 2025.
AirlineCheapestAverageFlexibilityOn-time
SWISSCheapest$377Average$544FlexibilityNo cancel feeOn-time79%
TAP AIR PORTUGALCheapest$454Average$733FlexibilityNo cancel feeOn-timeN/A
Air EuropaCheapest$469Average$747FlexibilityNo cancel feeOn-time83%
Air CanadaCheapest$477Average$973FlexibilityNo cancel feeOn-time67%
American AirlinesCheapest$479Average$700FlexibilityNo cancel feeOn-time71%
LufthansaCheapest$494Average$652FlexibilityNo cancel feeOn-time76%
IberiaCheapest$503Average$686FlexibilityNo cancel feeOn-time77%
British AirwaysCheapest$527Average$693FlexibilityNo cancel feeOn-time70%
United AirlinesCheapest$559Average$843FlexibilityNo cancel feeOn-time69%
KLMCheapest$571Average$657FlexibilityNo cancel feeOn-time75%

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