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$533+ Cheap flights from Key Largo, FL to Portsmouth, England

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 10/13. Fares are subject to change and may not be available on all flights or dates of travel.
MIA — LHR
Oct 15 — Oct 221
Wed 10/15
Wed 10/22
1 adult, Economy
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Cheap flight deals from Key Largo to Portsmouth

Keep the following information in mind while searching for Key Largo to Portsmouth flight deals. Data was last updated September 15, 2025.

Round-trip from

$764
(Trip.com)

One-way from

$533
(Delta)

Popular in

March

Cheapest in

September

Average price

$787
From Key Largo to Portsmouth
Search Deals
One-way flight from Key Largo to Portsmouth
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Highest demand for flights based on searches. 4% potential increase in price ($52 potential increase over avg. RT price).
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Cheapest flight prices on average. 6% potential price decrease ($70 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 Key Largo to Portsmouth

Cheapest flights from Key Largo to Portsmouth
Explore the most affordable flight options available from Key Largo to Portsmouth. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 15, 2025.

This Trip.com deal was found by Cheapflights users on 9/14. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/305:40 pmMIA - SOU
2 stops22h 00mMultiple Airlines
Thu 11/68:10 pmSOU - MIA
2 stops23h 30mMultiple Airlines
Deal found 9/14$764
This Ovago deal was found by Cheapflights users on 9/14. 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 Ovago is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/306:35 amMIA - SOU
2 stops22h 10mAer Lingus
Thu 11/68:10 pmSOU - MIA
1 stop26h 00mAer Lingus
Deal found 9/14$899
This Mytrip deal was found by Cheapflights users on 9/13. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/139:49 amMIA - SOU
3 stops28h 41mMultiple Airlines
Mon 10/209:40 amSOU - MIA
2 stops34h 05mMultiple Airlines
Deal found 9/13$939
This Delta deal was found by Cheapflights users on 9/13. 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.
Mon 10/1311:16 amMIA - SOU
2 stops16h 29mDelta
Mon 10/209:20 amSOU - MIA
2 stops17h 07mDelta
Deal found 9/13$980
This KAYAK deal was found by Cheapflights users on 9/14. 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 KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/147:05 pmMIA - SOU
1 stop19h 35mAer Lingus
Tue 1/64:05 pmSOU - MIA
1 stop30h 55mAer Lingus
Deal found 9/14$995
This Delta deal was found by Cheapflights users on 9/14. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/144:50 pmMIA - SOU
1 stop19h 35mDelta
Tue 1/65:30 pmSOU - MIA
2 stops28h 14mDelta
Deal found 9/14$1,041

Cheapflights Fare Finder

 
Customize your flight search to find flights from Key Largo to Portsmouth 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 15, 2025.
Use the filters below to find and compare flights from Key Largo to Portsmouth that are best for you.

Fly from

Key Largo

Fly to

Portsmouth

Route

Depart

Return

Price

MiamiSouthampton

MIA - SOU

MIASOU

Miami

Thu 10/30

5:40 pm-7:40 pm

2 stops22h 00m

Southampton Eastleigh

Thu 11/6

8:10 pm-2:40 pm

2 stops23h 30m

$764

MiamiSouthampton

MIA - SOU

MIASOU

Miami

Thu 10/30

6:35 am-8:45 am

2 stops22h 10m

Southampton Eastleigh

Thu 11/6

8:10 pm-5:10 pm

1 stop26h 00m

$899

MiamiSouthampton

MIA - SOU

MIASOU

Miami

Wed 2/25

7:55 pm-8:45 am

1 stop31h 50m

Southampton Eastleigh

Sun 3/1

9:30 am-6:00 pm

1 stop13h 30m

$915

MiamiSouthampton

MIA - SOU

MIASOU

Miami

Thu 2/5

1:46 pm-3:35 pm

2 stops20h 49m

Southampton Eastleigh

Sun 2/15

9:30 am-6:00 pm

1 stop13h 30m

$938

MiamiSouthampton

MIA - SOU

MIASOU

Miami

Thu 3/5

4:50 pm-5:00 pm

1 stop19h 10m

Southampton Eastleigh

Mon 3/9

8:50 am-3:50 pm

1 stop35h 00m

$939

MiamiSouthampton

MIA - SOU

MIASOU

Miami

Mon 10/13

9:49 am-7:30 pm

3 stops28h 41m

Southampton Eastleigh

Mon 10/20

9:40 am-2:45 pm

2 stops34h 05m

$939

MiamiSouthampton

MIA - SOU

MIASOU

Miami

Thu 3/5

8:05 am-8:05 am

2 stops19h 00m

Southampton Eastleigh

Mon 3/9

5:30 pm-3:50 pm

1 stop26h 20m

$943

MiamiSouthampton

MIA - SOU

MIASOU

Miami

Mon 10/13

11:16 am-5:00 pm

2 stops24h 44m

$533

MiamiSouthampton

MIA - SOU

MIASOU

Miami

Tue 10/14

12:05 pm-8:45 am

2 stops15h 40m

$533

MiamiSouthampton

MIA - SOU

MIASOU

Miami

Wed 10/15

7:05 am-5:00 pm

2 stops28h 55m

$533

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/15

Showing 1-10 of 18 results
1
2

Best time to book a flight from Key Largo to Portsmouth

Have a flexible travel schedule? Discover the best time to fly to Portsmouth 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 Portsmouth

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

Currently, November is the cheapest month in which you can book a flight from Key Largo to Portsmouth (average of $661). Flying from Key Largo to Portsmouth in June is currently the most expensive (average of $1,097). 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 P0R?

Find hourly flight availability from Key Largo to Portsmouth. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated September 15, 2025.

When flying from Key Largo to Portsmouth, 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 Portsmouth?

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

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

Weekly flight availability from Key Largo to Portsmouth

Explore weekly flight availability from Key Largo to Portsmouth. 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 September 15, 2025.

The most flights from KE9 to P0R are scheduled on a Monday (26 on average). You will have fewer flight options on Monday, which is when the least amount of flights are scheduled (26 on average).

Reviews of airlines servicing Portsmouth

Get insights into the airlines that provide service to Portsmouth. 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 Portsmouth. Reviews last updated September 15, 2025.
Peruse reviews from past customers who have flown with Delta from Key Largo to Portsmouth to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Delta
8.0
Very good
7,954 reviews

Entertainment

7.9

Crew

8.5

Comfort

7.9

Overall

8.0

Food

7.3

Boarding

8.2

Reviews

1 / 20
6.0
Good

pilar,May 2025

RSW - ATL

The stewardess was not very nice because I requested two glasses of water. She didn’t even offer the snacks to me. She seemed angry and I felt very bad about her reaction. Also, the flight was full and you could not move. The airline should provide seats for obese people in consideration to the rest pf the passengers.
Delta
8.0
Very good
7,954 reviews
Delta
8.0
Very good
7,954 reviews

Entertainment

7.9

Crew

8.5

Comfort

7.9

Overall

8.0

Food

7.3

Boarding

8.2

Reviews

1 / 20
6.0
Good

pilar,May 2025

RSW - ATL

The stewardess was not very nice because I requested two glasses of water. She didn’t even offer the snacks to me. She seemed angry and I felt very bad about her reaction. Also, the flight was full and you could not move. The airline should provide seats for obese people in consideration to the rest pf the passengers.

Related info for your journey

Find useful and relevant information for your journey from Key Largo to Portsmouth. 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 Key Largo to Portsmouth?

    Airlines like Aer Lingus fly from Key Largo to Portsmouth in about 22h 10m. The time it takes to get you to your destination can typically vary by up to . Key Largo and Portsmouth are separated by a distance of 4381 mi.

  • What are the most reliable airlines from Key Largo to Portsmouth?

    No one likes to see their flight delayed. When booking a flight from Key Largo to Portsmouth consider choosing Air France (87%), KLM (86%) or Delta (86%) as they are the most reliable in getting you off to your destination on time.

  • What are the cheapest flights from Key Largo to Portsmouth?

    While on average a flight from Key Largo to Portsmouth is generally $2,616, our data shows the cheapest flight currently is $399. When looking at the most popular route, (Miami - Southampton Eastleigh), you can expect to pay $764 for that flight.

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

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

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

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

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

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

    Currently, November is the cheapest month in which you can book a flight from Key Largo to Portsmouth (average of $661). Flying from Key Largo to Portsmouth in June is currently the most expensive (average of $1,097). 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

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Top 10 airlines flying from Key Largo to Portsmouth

Discover the top 10 airlines that operate flights from Key Largo to Portsmouth. 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 15, 2025.
AirlineCheapestAverageFlexibilityOn-time
JetBlueCheapest$51Average$727FlexibilityNo cancel feeOn-time62%
Scandinavian AirlinesCheapest$203Average$573FlexibilityNo cancel feeOn-time77%
Norse Atlantic UKCheapest$346Average$570FlexibilityNo cancel feeOn-timeN/A
Air CanadaCheapest$369Average$647FlexibilityNo cancel feeOn-time67%
KLMCheapest$431Average$629FlexibilityNo cancel feeOn-time75%
British AirwaysCheapest$460Average$739FlexibilityNo cancel feeOn-time70%
DeltaCheapest$460Average$892FlexibilityNo cancel feeOn-timeN/A
Virgin AtlanticCheapest$467Average$756FlexibilityNo cancel feeOn-time72%
American AirlinesCheapest$514Average$796FlexibilityNo cancel feeOn-time71%
TAP AIR PORTUGALCheapest$547Average$769FlexibilityNo cancel feeOn-timeN/A

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