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$270+ 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 2/5. Fares are subject to change and may not be available on all flights or dates of travel.
MIA — OPO
ene. 14 — ene. 211
mié. 1/14
mié. 1/21
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 86 days in advance, depart on a Tuesday or Wednesday and return on a Thursday

Cheap 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 diciembre 15, 2025.

This Delta deal was found by Cheapflights users on 12/15. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 12/2910:40 pmMIA - OPO
1 stop30h 50mDelta
mar. 1/135:00 amOPO - MIA
1 stop14h 50mDelta
Deal found 12/15$480
This Delta deal was found by Cheapflights users on 12/13. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 12/3111:45 amMIA - OPO
2 stops17h 45mDelta
mar. 1/135:00 amOPO - MIA
1 stop14h 50mDelta
Deal found 12/13$482
This Delta deal was found by Cheapflights users on 12/15. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 12/317:25 amMIA - OPO
2 stops22h 05mDelta
mié. 1/2111:15 amOPO - MIA
1 stop32h 35mDelta
Deal found 12/15$483
This KLM deal was found by Cheapflights users on 12/14. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 12/304:50 pmMIA - OPO
1 stop12h 40mKLM
mar. 1/135:00 amOPO - MIA
1 stop14h 50mKLM
Deal found 12/14$484
This Delta deal was found by Cheapflights users on 12/15. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 12/2910:40 pmMIA - OPO
1 stop30h 50mDelta
mié. 1/1411:25 amOPO - MIA
1 stop13h 55mDelta
Deal found 12/15$486
This Delta deal was found by Cheapflights users on 12/15. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 12/2910:40 pmMIA - OPO
1 stop30h 50mDelta
sáb. 1/1711:15 amOPO - MIA
1 stop32h 35mDelta
Deal found 12/15$488
This Delta deal was found by Cheapflights users on 12/15. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 12/318:20 amMIA - OPO
2 stops21h 10mDelta
mié. 1/1411:25 amOPO - MIA
1 stop13h 55mDelta
Deal found 12/15$489
This Delta deal was found by Cheapflights users on 12/15. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 12/2910:40 pmMIA - OPO
1 stop30h 50mDelta
lun. 1/1211:15 amOPO - MIA
2 stops37h 31mDelta
Deal found 12/15$490
This KLM deal was found by Cheapflights users on 12/14. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 12/304:50 pmMIA - OPO
1 stop24h 35mKLM
mar. 1/205:00 amOPO - MIA
2 stops18h 20mKLM
Deal found 12/14$494
This British Airways deal was found by Cheapflights users on 12/13. 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 British Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 12/305:20 pmMIA - OPO
1 stop17h 40mIberia
mar. 1/2012:25 pmOPO - MIA
1 stop13h 20mIberia
Deal found 12/13$495
This KLM deal was found by Cheapflights users on 12/15. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 12/317:27 pmMIA - OPO
2 stops14h 58mKLM
sáb. 1/1711:15 amOPO - MIA
1 stop32h 35mKLM
Deal found 12/15$497

Find 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 diciembre 15, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$420
(eDestinos)

One-way from

$270
(French Bee)

Popular in

December

Cheapest in

February

Average price

$916
Provider with most accurate pricing for Miami-Porto flight deals.
Search Deals
Provider most trusted by Cheapflights users for Miami-Porto flights.
Search Deals
From Key Largo to Porto
Search Deals
One-way flight from Key Largo to Porto
Search Deals
Highest demand for flights based on searches. 0% potential increase in price ($6 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($21 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in December 2025
Search Deals

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 diciembre 15, 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

vie. 2/13

4:35 pm-12:10 pm

1 stop14h 35m

Porto

sáb. 2/21

10:00 am-2:50 pm

1 stop33h 50m

$452

MiamiPorto

MIA - OPO

MIAOPO

Miami

mar. 1/27

12:25 pm-11:40 am

2 stops18h 15m

Porto

mar. 2/3

6:00 am-12:16 am

2 stops23h 16m

$474

MiamiPorto

MIA - OPO

MIAOPO

Miami

mar. 3/10

11:40 pm-10:30 am

1 stop30h 50m

Porto

lun. 3/16

4:10 pm-3:50 pm

1 stop27h 40m

$480

MiamiPorto

MIA - OPO

MIAOPO

Miami

mié. 12/31

12:45 pm-10:30 am

2 stops16h 45m

Porto

mar. 1/13

5:00 am-2:50 pm

1 stop14h 50m

$483

MiamiPorto

MIA - OPO

MIAOPO

Miami

mar. 12/30

4:50 pm-10:30 am

1 stop12h 40m

Porto

mar. 1/13

5:00 am-2:50 pm

1 stop14h 50m

$484

MiamiPorto

MIA - OPO

MIAOPO

Miami

mar. 12/30

4:50 pm-10:30 am

1 stop12h 40m

Porto

mar. 1/20

5:00 am-2:50 pm

1 stop14h 50m

$484

MiamiPorto

MIA - OPO

MIAOPO

Miami

mié. 12/31

8:45 am-10:30 am

2 stops20h 45m

Porto

mar. 1/13

11:15 am-9:41 pm

2 stops39h 26m

$493

MiamiPorto

MIA - OPO

MIAOPO

Miami

mar. 3/10

11:23 am-10:30 am

2 stops19h 07m

Porto

lun. 3/16

11:25 am-9:20 pm

1 stop13h 55m

$497

MiamiPorto

MIA - OPO

MIAOPO

Miami

mié. 12/31

7:27 pm-3:25 pm

2 stops14h 58m

Porto

sáb. 1/17

11:15 am-2:50 pm

1 stop32h 35m

$497

MiamiPorto

MIA - OPO

MIAOPO

Miami

jue. 2/5

9:10 pm-4:20 pm

1 stop14h 10m

$270

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/15

Showing 1-10 of 18 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 December 12, 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 86 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, February is the cheapest month in which you can book a flight from Key Largo to Porto (average of $438). Flying from Key Largo to Porto in June is currently the most expensive (average of $599). 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 diciembre 15, 2025.

A simple way to save on the total cost of your ticket is to fly from Key Largo to Porto in the morning. If you’re flexible enough to do this you can expect to save up to 34% on your trip compared to booking a flight in the afternoon.

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 evenings when fares are most often at their lowest. Sunday at noon flights should be avoided if possible as fares are typically the most expensive at this time.

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 diciembre 15, 2025.
See what other customers who have flown with United Airlines, TAP AIR PORTUGAL, and Air Canada from Key Largo to Porto 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
9,093 reviews

Overall

7.4

Crew

8.1

Food

6.6

Boarding

7.7

Comfort

7.3

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

Sunderesh,Dec 2025

AUS - EWR

Smooth flight from Austin to Newark. The crew was friendly.
United Airlines
7.4
Good
9,093 reviews
United Airlines
7.4
Good
9,093 reviews

Overall

7.4

Crew

8.1

Food

6.6

Boarding

7.7

Comfort

7.3

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

Sunderesh,Dec 2025

AUS - EWR

Smooth flight from Austin to Newark. The crew was friendly.
TAP AIR PORTUGAL
7.2
Good
2,089 reviews
United Airlines
7.4
Good
9,093 reviews

Overall

7.4

Crew

8.1

Food

6.6

Boarding

7.7

Comfort

7.3

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

Sunderesh,Dec 2025

AUS - EWR

Smooth flight from Austin to Newark. The crew was friendly.
Air Canada
7.1
Good
10,527 reviews
United Airlines
7.4
Good
9,093 reviews

Overall

7.4

Crew

8.1

Food

6.6

Boarding

7.7

Comfort

7.3

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

Sunderesh,Dec 2025

AUS - EWR

Smooth flight from Austin to Newark. The crew was friendly.
Air Europa
7.0
Good
571 reviews
United Airlines
7.4
Good
9,093 reviews

Overall

7.4

Crew

8.1

Food

6.6

Boarding

7.7

Comfort

7.3

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

Sunderesh,Dec 2025

AUS - EWR

Smooth flight from Austin to Newark. The crew was friendly.
Iberia
7.0
Good
3,052 reviews
United Airlines
7.4
Good
9,093 reviews

Overall

7.4

Crew

8.1

Food

6.6

Boarding

7.7

Comfort

7.3

Entertainment

7.1

Reviews

1 / 20
10.0
Excellent

Sunderesh,Dec 2025

AUS - EWR

Smooth flight from Austin to Newark. The crew was friendly.

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.

  • How long is the flight from Key Largo to Porto?

    For as low as $452, TAP AIR PORTUGAL can have you in Porto from Key Largo in 14h 35m. There are 4140 mi between Key Largo and Porto. Both multi-stop and nonstop flights can be found to your destination and back.

  • 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 $253. However, be on the lookout for offers from Air Europa and United Airlines, 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, February is the cheapest month in which you can book a flight from Key Largo to Porto (average of $438). Flying from Key Largo to Porto in June is currently the most expensive (average of $599). 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
Vila Nova de Gaia

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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 diciembre 15, 2025.
AirlineCheapestAverageFlexibilityOn-time
Air EuropaCheapest$476Average$725FlexibilityNo cancel feeOn-time83%
TAP AIR PORTUGALCheapest$483Average$764FlexibilityNo cancel feeOn-timeN/A
DeltaCheapest$492Average$703FlexibilityNo cancel feeOn-timeN/A
KLMCheapest$494Average$614FlexibilityNo cancel feeOn-time75%
SWISSCheapest$507Average$643FlexibilityNo cancel feeOn-time79%
American AirlinesCheapest$518Average$779FlexibilityNo cancel feeOn-time71%
British AirwaysCheapest$521Average$693FlexibilityNo cancel feeOn-time70%
United AirlinesCheapest$532Average$732FlexibilityNo cancel feeOn-time69%
LufthansaCheapest$550Average$688FlexibilityNo cancel feeOn-time76%
Air CanadaCheapest$553Average$876FlexibilityNo cancel feeOn-time67%

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