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Key Largo

$107+ Cheap flights from St. Louis (STL) to Key Largo, FL

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 5/6. Fares are subject to change and may not be available on all flights or dates of travel.
STL — MIA
mar. 8 — mar. 151
sáb. 3/8
sáb. 3/15
1 adult, Economy
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The best prices from Lambert-St Louis to Key Largo are usually found in September or August, booked 63 days in advance, depart on a Friday or Sunday and return on a Saturday

Cheap flight deals from St. Louis to Key Largo

Keep the following information in mind while searching for St. Louis to Key Largo flight deals. Data was last updated marzo 3, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$270
(CheapOair)

One-way from

$107
(Mytrip)

Popular in

March

Cheapest in

September

Average price

$499
Provider with most accurate pricing for Lambert-St Louis-Miami flight deals.
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Provider most trusted by Cheapflights users for Lambert-St Louis-Miami flights.
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From Lambert-St Louis to Key Largo
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One-way flight from Lambert-St Louis to Key Largo
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Highest demand for flights based on searches. 9% potential increase in price ($40 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($10 potential savings vs. average RT price).
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Average for round-trip flights in March 2025
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Find flight deals from St. Louis to Key Largo

Cheapest flights from St. Louis to Key Largo
Explore the most affordable flight options available from St. Louis to Key Largo. Find the lowest fares from popular airlines and budget airlines, with prices last updated on marzo 3, 2025.

This CheapOair deal was found by Cheapflights users on 3/3. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 3/106:58 pmSTL - MIA
1 stop9h 18mFrontier
jue. 3/136:25 amMIA - STL
1 stop27h 51mFrontier
Deal found 3/3$267
This Mytrip deal was found by Cheapflights users on 3/2. 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.
mar. 3/115:38 pmSTL - MIA
2 stops26h 02mSpirit Airlines
lun. 3/1710:25 pmMIA - STL
2 stops19h 17mSpirit Airlines
Deal found 3/2$273
This American Airlines deal was found by Cheapflights users on 3/2. 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.
mié. 3/197:13 amSTL - MIA
1 stop5h 08mAmerican Airlines
mié. 3/269:50 pmMIA - STL
Nonstop3h 06mAmerican Airlines
Deal found 3/2$274
This Delta deal was found by Cheapflights users on 3/2. 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.
jue. 4/241:46 pmSTL - MIA
1 stop6h 32mDelta
mar. 5/612:00 pmMIA - STL
1 stop5h 26mDelta
Deal found 3/2$276
This Mytrip deal was found by Cheapflights users on 3/1. 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.
mié. 4/912:15 pmSTL - MIA
2 stops33h 57mMultiple Airlines
lun. 4/145:45 amMIA - STL
3 stops36h 30mMultiple Airlines
Deal found 3/1$278
This Southwest deal was found by Cheapflights users on 3/1. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 3/266:15 amSTL - MIA
2 stops7h 40mSouthwest
mié. 4/27:05 amMIA - STL
1 stop7h 30mSouthwest
Deal found 3/1$284
This United Airlines deal was found by Cheapflights users on 3/3. 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.
lun. 3/173:30 pmSTL - MIA
1 stop6h 15mUnited Airlines
jue. 3/204:48 pmMIA - STL
1 stop6h 19mUnited Airlines
Deal found 3/3$387

Find flights from St. Louis to Key Largo within your budget

Customize your flight search to find flights from St. Louis to Key Largo 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 marzo 3, 2025.

Fly from

St. Louis

Fly to

Key Largo

Route

Depart

Return

Price

St. LouisMiami

STL - MIA

STLMIA

Lambert-St Louis

lun. 3/17

6:58 pm-5:16 am

1 stop9h 18m

Miami

jue. 3/20

6:25 am-9:16 am

1 stop27h 51m

$270

St. LouisMiami

STL - MIA

STLMIA

Lambert-St Louis

vie. 4/4

5:15 pm-12:59 am

3 stops30h 44m

Miami

mié. 4/9

8:58 am-5:15 pm

2 stops33h 17m

$273

St. LouisMiami

STL - MIA

STLMIA

Lambert-St Louis

mié. 3/19

7:13 am-1:21 pm

1 stop5h 08m

Miami

mié. 3/26

9:50 pm-11:56 pm

Nonstop3h 06m

$274

St. LouisMiami

STL - MIA

STLMIA

Lambert-St Louis

jue. 4/24

1:46 pm-9:18 pm

1 stop6h 32m

Miami

mar. 5/6

12:00 pm-4:26 pm

1 stop5h 26m

$276

St. LouisMiami

STL - MIA

STLMIA

Lambert-St Louis

mié. 3/26

6:15 am-2:55 pm

2 stops7h 40m

Miami

mié. 4/2

7:05 am-1:35 pm

1 stop7h 30m

$284

St. LouisMiami

STL - MIA

STLMIA

Lambert-St Louis

lun. 3/17

3:30 pm-10:45 pm

1 stop6h 15m

Miami

jue. 3/20

4:48 pm-10:07 pm

1 stop6h 19m

$387

St. LouisMiami

STL - MIA

STLMIA

Lambert-St Louis

mar. 5/6

6:10 pm-7:45 pm

2 stops24h 35m

$107

St. LouisMiami

STL - MIA

STLMIA

Lambert-St Louis

mié. 4/30

5:55 pm-9:35 pm

Nonstop2h 40m

$120

St. LouisMiami

STL - MIA

STLMIA

Lambert-St Louis

lun. 6/30

6:55 pm-5:24 am

1 stop9h 29m

$122

St. LouisMiami

STL - MIA

STLMIA

Lambert-St Louis

lun. 4/21

5:15 pm-11:12 pm

2 stops28h 57m

$124

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/2

Showing 1-10 of 14 results
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Best time to book a flight from St. Louis to Key Largo

Have a flexible travel schedule? Discover the best time to fly to Key Largo from St. Louis 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.

Travel insights for flights from St. Louis to Key Largo

Get recent, data-driven insights about flights from St. Louis to Key Largo including ideal travel times, pricing trends, and more.

How far ahead should I book a flight from St. Louis to Key Largo?

Use this chart to determine the optimal time to book a round-trip flight from St. Louis to Key Largo. Price data was last updated on February 28, 2025.

To ensure you get the cheapest price possible for a flight from St. Louis to Key Largo, you should look to book at least 63 days in advance of your intended travel date. The price of your flight may increase if you delay and leave booking until a week or so before departure.

What is the cheapest month to book a flight from St. Louis to Key Largo?

Currently, September is the cheapest month in which you can book a flight from St. Louis to Key Largo (average of $231). Flying from St. Louis to Key Largo in March is currently the most expensive (average of $289). 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 STL to KE9?

Find hourly flight availability from St. Louis to Key Largo. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated marzo 3, 2025.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from St. Louis to Key Largo as you normally would.

What is the cheapest day to fly from St. Louis to Key Largo?

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

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

Rainfall in Key Largo by month

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

In terms of precipitation, rainfall in Key Largo ranges from 1.6 - 9.9 inches per month. September is typically the wettest month, when rainfall can reach 9.9 in. January is typically the driest time to visit Key Largo when rainfall is around 1.6 in.

Temperature in Key Largo by month

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

If weather is an important factor for your trip to Key Largo, 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 84.2 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 68.0 F).

Reviews of airlines servicing Key Largo

Get insights into the airlines that provide service to Key Largo. 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 Key Largo. Reviews last updated marzo 3, 2025.
Peruse reviews from past customers who have flown with Southwest, Alaska Airlines and Delta from St. Louis to Key Largo to help guide your decision. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.1
Very good
4,333 reviews

Entertainment

7.6

Crew

8.7

Boarding

8.2

Comfort

8.1

Food

7.1

Overall

8.1

Reviews

1 / 20

8.0
Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.

Southwest
8.1
Very good
4,333 reviews
Southwest
8.1
Very good
4,333 reviews

Entertainment

7.6

Crew

8.7

Boarding

8.2

Comfort

8.1

Food

7.1

Overall

8.1

Reviews

1 / 20

8.0
Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.

Alaska Airlines
8.0
Very good
9,713 reviews
Southwest
8.1
Very good
4,333 reviews

Entertainment

7.6

Crew

8.7

Boarding

8.2

Comfort

8.1

Food

7.1

Overall

8.1

Reviews

1 / 20

8.0
Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.

Delta
8.0
Very good
8,070 reviews
Southwest
8.1
Very good
4,333 reviews

Entertainment

7.6

Crew

8.7

Boarding

8.2

Comfort

8.1

Food

7.1

Overall

8.1

Reviews

1 / 20

8.0
Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.

United Airlines
7.4
Good
8,679 reviews
Southwest
8.1
Very good
4,333 reviews

Entertainment

7.6

Crew

8.7

Boarding

8.2

Comfort

8.1

Food

7.1

Overall

8.1

Reviews

1 / 20

8.0
Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.

American Airlines
7.2
Good
10,000 reviews
Southwest
8.1
Very good
4,333 reviews

Entertainment

7.6

Crew

8.7

Boarding

8.2

Comfort

8.1

Food

7.1

Overall

8.1

Reviews

1 / 20

8.0
Excellent

Ila,Mar 2025

HOU - DAL

Our original flight was delayed. We were able to change our flight and got home at close to the same time. Looking forward to when you have assigned seating.

Related info for your journey

Find useful and relevant information for your journey from St. Louis to Key Largo. 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 from for flights from St. Louis to Key Largo?

    For a flight from St. Louis to Key Largo, you will be flying from Lambert-St Louis. Lambert-St Louis (STL) is just 12.7 mi from the center of the city. Lambert-St Louis is the only St. Louis airport and it handles 4 outbound flights to Key Largo per day. 6 airlines have flights to Key Largo from Lambert-St Louis on a regular basis.

  • How popular is this St. Louis to Key Largo flight route?

    The Lambert-St Louis to Key Largo flight path was viewed by 22 users in the past month. Keep an eye out for changes in search interest prior to high and low season.

  • What are the cheapest airlines to fly from St. Louis to Key Largo one-way?

    For one-way options, check prices for Spirit Airlines. According to our data, you can fly for as low as $107. Users have also found prices from $120 and $122 on Southwest and Frontier, respectively.

  • What are the most reliable airlines from St. Louis to Key Largo?

    The top 3 most reliable airlines when flying from St. Louis to Key Largo are Qatar Airways (84%), GOL (82%) and Southwest (79%).

  • What are the cheapest flights from St. Louis to Key Largo?

    On average you can expect to pay $478 for a flight from St. Louis to Key Largo. The cheapest flight overall is $119 while the most popular route, (Lambert-St Louis - Miami) is currently priced at $180.

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

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

  • How can I find direct flights from St. Louis to Key Largo?

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

  • Can I find deals for business class flights from St. Louis to Key Largo?

    Yes. Cheapflights offers flight deals from St. Louis to Key Largo 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 St. Louis to Key Largo?

    Currently, September is the cheapest month in which you can book a flight from St. Louis to Key Largo (average of $231). Flying from St. Louis to Key Largo in March is currently the most expensive (average of $289). 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.

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Top 6 airlines flying from St. Louis to Key Largo

Discover the top 6 airlines that operate flights from St. Louis to Key Largo. 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 marzo 3, 2025.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$68Average$145FlexibilityNo cancel feeOn-time65%
FrontierCheapest$139Average$236FlexibilityNo cancel feeOn-time62%
DeltaCheapest$208Average$426FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$236Average$415FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$268Average$499FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$291Average$471FlexibilityNo cancel feeOn-time63%
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