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$270+ 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 2/3. Fares are subject to change and may not be available on all flights or dates of travel.
MIA — LHR
Feb 28 — Mar 71
Sat 2/28
Sat 3/7
1 adult, Economy
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Cheap 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 January 29, 2026.

This KLM deal was found by Cheapflights users on 1/27. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/1911:35 am
MIA
-
SOU
2 stops16h 10m
KLM
Sun 9/279:15 am
SOU
-
MIA
2 stops18h 58m
KLM
Deal found 1/27$915
This Expedia deal was found by Cheapflights users on 1/27. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/194:55 pm
MIA
-
SOU
1 stop10h 50m
Multiple Airlines
Sun 9/278:45 pm
SOU
-
MIA
2 stops22h 45m
Multiple Airlines
Deal found 1/27$978
This Trip.com deal was found by Cheapflights users on 1/27. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/115:00 pm
MIA
-
SOU
2 stops19h 40m
Multiple Airlines
Sun 10/182:50 pm
SOU
-
MIA
2 stops34h 25m
Multiple Airlines
Deal found 1/27$1,001
This Delta deal was found by Cheapflights users on 1/27. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/2611:20 am
MIA
-
SOU
2 stops24h 30m
Delta
Wed 6/105:20 pm
SOU
-
MIA
1 stop26h 25m
Delta
Deal found 1/27$1,044
This Delta deal was found by Cheapflights users on 1/27. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 6/111:20 am
MIA
-
SOU
2 stops16h 15m
Delta
Thu 6/45:20 pm
SOU
-
MIA
2 stops30h 25m
Delta
Deal found 1/27$1,053
This Delta deal was found by Cheapflights users on 1/27. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/2611:20 am
MIA
-
SOU
2 stops24h 30m
Delta
Fri 6/59:05 am
SOU
-
MIA
2 stops19h 08m
Delta
Deal found 1/27$1,054
This Delta deal was found by Cheapflights users on 1/28. 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 5/197:55 pm
MIA
-
SOU
2 stops39h 55m
Delta
Mon 6/15:20 pm
SOU
-
MIA
1 stop26h 25m
Delta
Deal found 1/28$1,078
This Priceline deal was found by Cheapflights users on 1/26. 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/15:00 pm
MIA
-
SOU
2 stops34h 40m
Aer Lingus
Sat 8/159:10 am
SOU
-
MIA
2 stops20h 36m
Aer Lingus
Deal found 1/26$1,093
This Delta deal was found by Cheapflights users on 1/27. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 6/111:20 am
MIA
-
SOU
2 stops16h 15m
Delta
Fri 6/55:20 pm
SOU
-
MIA
1 stop26h 25m
Delta
Deal found 1/27$1,104

Find 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 January 29, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$1,044
(Delta)

One-way from

$270
(Kiwi.com)

Popular in

December

Cheapest in

February

Average price

$641
Provider with most accurate pricing for Miami-London (LON) flight deals.
Search Deals
Provider most trusted by Cheapflights users for Miami-London (LON) flights.
Search Deals
From Key Largo to Portsmouth
Search Deals
One-way flight from Key Largo to Portsmouth
Search Deals
Highest demand for flights based on searches. 14% potential increase in price ($116 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 4% potential price decrease ($29 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in January 2026
Search Deals

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 January 29, 2026.
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

Mon 6/1

11:20 am-8:35 am

2 stops16h 15m

Southampton Eastleigh

Wed 6/10

5:20 pm-2:45 pm

1 stop26h 25m

$1,044

MiamiSouthampton

MIA - SOU

MIASOU

Miami

Wed 5/27

11:20 am-4:50 pm

2 stops24h 30m

Southampton Eastleigh

Wed 6/10

5:20 pm-2:45 pm

1 stop26h 25m

$1,044

MiamiSouthampton

MIA - SOU

MIASOU

Miami

Wed 5/27

7:00 am-8:35 am

2 stops20h 35m

Southampton Eastleigh

Thu 6/4

5:20 pm-5:09 pm

2 stops28h 49m

$1,053

MiamiSouthampton

MIA - SOU

MIASOU

Miami

Wed 5/27

7:00 am-8:35 am

2 stops20h 35m

Southampton Eastleigh

Tue 6/9

5:20 pm-5:21 pm

2 stops29h 01m

$1,053

MiamiSouthampton

MIA - SOU

MIASOU

Miami

Tue 5/26

11:20 am-8:35 am

2 stops16h 15m

Southampton Eastleigh

Thu 6/4

5:20 pm-5:21 pm

2 stops29h 01m

$1,053

MiamiSouthampton

MIA - SOU

MIASOU

Miami

Mon 6/1

11:20 am-8:35 am

2 stops16h 15m

Southampton Eastleigh

Thu 6/4

5:20 pm-6:45 pm

2 stops30h 25m

$1,053

MiamiSouthampton

MIA - SOU

MIASOU

Miami

Mon 6/1

11:20 am-8:35 am

2 stops16h 15m

Southampton Eastleigh

Mon 6/8

5:20 pm-5:09 pm

2 stops28h 49m

$1,053

MiamiSouthampton

MIA - SOU

MIASOU

Miami

Mon 6/1

11:20 am-8:35 am

2 stops16h 15m

Southampton Eastleigh

Fri 6/5

9:05 am-11:13 pm

2 stops19h 08m

$1,054

MiamiSouthampton

MIA - SOU

MIASOU

Miami

Tue 5/26

11:20 am-4:50 pm

2 stops24h 30m

Southampton Eastleigh

Fri 6/5

9:05 am-11:13 pm

2 stops19h 08m

$1,054

MiamiSouthampton

MIA - SOU

MIASOU

Miami

Mon 6/8

11:15 am-8:35 am

2 stops16h 20m

Southampton Eastleigh

Tue 6/16

9:05 am-5:09 pm

2 stops37h 04m

$1,054

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/27

Showing 1-10 of 19 results
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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, January is the cheapest month in which you can book a flight from Key Largo to Portsmouth (average of $284). Flying from Key Largo to Portsmouth in December is currently the most expensive (average of $592). 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 January 29, 2026.

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.

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 January 29, 2026.

The most flights from KE9 to P0R are scheduled on a Monday (18 on average). You will have fewer flight options on Thursday, which is when the least amount of flights are scheduled (14 on average).

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 Delta fly from Key Largo to Portsmouth in about 16h 15m. 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 KLM (82%), Air France (82%) or Delta (82%) 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 $2,738, our data shows the cheapest flight currently is $211. When looking at the most popular route, (Miami - Southampton Eastleigh), you can expect to pay $1,149 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, January is the cheapest month in which you can book a flight from Key Largo to Portsmouth (average of $284). Flying from Key Largo to Portsmouth in December is currently the most expensive (average of $592). 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 January 29, 2026.
AirlineCheapestAverageFlexibilityOn-time
JetBlueCheapest$51Average$781FlexibilityNo cancel feeOn-time62%
Norse Atlantic UKCheapest$340Average$589FlexibilityNo cancel feeOn-timeN/A
British AirwaysCheapest$358Average$708FlexibilityNo cancel feeOn-time70%
DeltaCheapest$461Average$745FlexibilityNo cancel feeOn-timeN/A
TAP AIR PORTUGALCheapest$464Average$696FlexibilityNo cancel feeOn-timeN/A
Scandinavian AirlinesCheapest$483Average$580FlexibilityNo cancel feeOn-time77%
Virgin AtlanticCheapest$490Average$765FlexibilityNo cancel feeOn-time72%
FinnairCheapest$515Average$878FlexibilityNo cancel feeOn-time76%
American AirlinesCheapest$520Average$800FlexibilityNo cancel feeOn-time71%
IberiaCheapest$530Average$773FlexibilityNo cancel feeOn-time77%

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