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$62+ Cheap flights from Key Largo, FL to St. Louis (STL)

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 3/13. Fares are subject to change and may not be available on all flights or dates of travel.
MIA — STL
Jan 26 — Feb 21
Sun 1/26
Sun 2/2
1 adult, Economy
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The best prices from Key Largo to Lambert-St Louis are usually found in September or July, booked 59 days in advance, depart on a Saturday or Thursday and return on a Friday

Cheap flight deals from Key Largo to St. Louis

Discover tips and strategies to find the most affordable flight options for your journey from Key Largo (KE9) to St. Louis (STL). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated January 21, 2025.

Round-trip from

$170
(CheapOair)

One-way from

$62
(Trip.com)

Popular in

January

Cheapest in

September

Average price

$576
From Key Largo to Lambert-St Louis
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One-way flight from Key Largo to Lambert-St Louis
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Highest demand for flights based on searches. 16% potential increase in price ($70 potential increase over avg. RT price).
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Cheapest flight prices on average. 5% potential price decrease ($19 potential savings vs. average RT price).
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Average for round-trip flights in January 2025
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Find flight deals from Key Largo to St. Louis

Cheapest flights from Key Largo to St. Louis
Explore the most affordable flight options available from Key Largo to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on January 21, 2025.

This CheapOair deal was found by Cheapflights users on 1/20. 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.
Fri 2/216:25 amMIA - STL
1 stop27h 51mFrontier
Mon 2/247:04 pmSTL - MIA
1 stop9h 12mFrontier
Deal found 1/20$170
This Delta deal was found by Cheapflights users on 1/21. 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 2/1110:28 amMIA - STL
1 stop6h 06mDelta
Tue 2/184:40 pmSTL - MIA
1 stop7h 11mDelta
Deal found 1/21$257
This Mytrip deal was found by Cheapflights users on 1/21. 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.
Sat 2/158:05 amMIA - STL
2 stops29h 05mMultiple Airlines
Tue 2/184:00 pmSTL - MIA
2 stops25h 25mMultiple Airlines
Deal found 1/21$261
This Southwest deal was found by Cheapflights users on 1/21. 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.
Sat 2/156:40 amMIA - STL
Nonstop3h 00mSouthwest
Tue 2/188:15 amSTL - MIA
Nonstop2h 45mSouthwest
Deal found 1/21$262
This American Airlines deal was found by Cheapflights users on 1/21. 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.
Tue 2/189:45 pmMIA - STL
Nonstop2h 55mAmerican Airlines
Tue 2/254:33 pmSTL - MIA
Nonstop2h 51mAmerican Airlines
Deal found 1/21$281
This United Airlines deal was found by Cheapflights users on 1/21. 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 2/116:15 amMIA - STL
2 stops10h 23mUnited Airlines
Mon 2/173:32 pmSTL - MIA
1 stop5h 42mUnited Airlines
Deal found 1/21$342
This Mytrip deal was found by Cheapflights users on 1/21. 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 3/249:53 pmMIA - STL
2 stops19h 29mSpirit Airlines
Thu 3/275:17 pmSTL - MIA
2 stops15h 52mSpirit Airlines
Deal found 1/21$532
This Alaska Airlines deal was found by Cheapflights users on 1/19. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 3/77:52 pmMIA - STL
2 stops19h 33mAlaska Airlines
Sun 3/97:00 amSTL - MIA
1 stop32h 50mAlaska Airlines
Deal found 1/19$553

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

Customize your flight search to find flights from Key Largo to St. Louis 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 21, 2025.

Fly from

Any airport

Fly to

Any airport

Route

Depart

Return

Price

MiamiSt. Louis

MIA - STL

MIASTL

Miami

Fri 2/21

6:25 am-9:16 am

1 stop27h 51m

Lambert-St Louis

Mon 2/24

7:04 pm-5:16 am

1 stop9h 12m

$170

MiamiSt. Louis

MIA - STL

MIASTL

Miami

Tue 2/11

6:00 am-11:46 am

1 stop6h 46m

Lambert-St Louis

Wed 2/12

4:40 pm-12:51 am

1 stop7h 11m

$257

MiamiSt. Louis

MIA - STL

MIASTL

Miami

Sat 2/15

8:05 am-12:10 pm

2 stops29h 05m

Lambert-St Louis

Tue 2/18

4:00 pm-6:25 pm

2 stops25h 25m

$261

MiamiSt. Louis

MIA - STL

MIASTL

Miami

Sat 2/15

6:40 am-8:40 am

Nonstop3h 00m

Lambert-St Louis

Tue 2/18

8:15 am-12:00 pm

Nonstop2h 45m

$262

MiamiSt. Louis

MIA - STL

MIASTL

Miami

Tue 2/18

9:45 pm-11:40 pm

Nonstop2h 55m

Lambert-St Louis

Tue 2/25

4:33 pm-8:24 pm

Nonstop2h 51m

$281

MiamiSt. Louis

MIA - STL

MIASTL

Miami

Tue 2/11

6:15 am-3:38 pm

2 stops10h 23m

Lambert-St Louis

Mon 2/17

3:32 pm-10:14 pm

1 stop5h 42m

$342

MiamiSt. Louis

MIA - STL

MIASTL

Miami

Mon 3/24

9:53 pm-4:22 pm

2 stops19h 29m

Lambert-St Louis

Thu 3/27

5:17 pm-10:09 am

2 stops15h 52m

$532

MiamiSt. Louis

MIA - STL

MIASTL

Miami

Fri 3/7

7:52 pm-2:25 pm

2 stops19h 33m

Lambert-St Louis

Sun 3/9

7:00 am-4:50 pm

1 stop32h 50m

$553

MiamiSt. Louis

MIA - STL

MIASTL

Miami

Thu 3/13

6:25 am-9:16 am

1 stop27h 51m

$62

MiamiSt. Louis

MIA - STL

MIASTL

Miami

Thu 2/27

6:00 pm-8:05 pm

Nonstop3h 05m

$119

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/20

Showing 1-10 of 15 results
1
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Best time to book a flight from Key Largo to St. Louis

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

Travel insights for flights from Key Largo to St. Louis

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

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

Use this chart to determine the optimal time to book a round-trip flight from Key Largo to St. Louis. Price data was last updated on January 17, 2025.

The price you pay for your flight from Key Largo to St. Louis may vary depending on when you book. For the best chance of a lower fare, look to book 58 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 St. Louis?

Currently, August is the cheapest month in which you can book a flight from Key Largo to St. Louis (average of $311). Flying from Key Largo to St. Louis in March is currently the most expensive (average of $356). 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 STL?

Find hourly flight availability from Key Largo to St. Louis. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated January 21, 2025.

When flying from Key Largo to St. Louis, 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 St. Louis?

Use this chart to determine the cheapest time to fly round-trip from Key Largo to St. Louis. Price data was last updated on June 23, 2024.

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

Weekly flight availability from Key Largo to St. Louis

Explore weekly flight availability from Key Largo to St. Louis. 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 21, 2025.

The most flights from KE9 to STL are scheduled on a Monday (7 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (3 on average).

Rainfall in St. Louis by month

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

In terms of precipitation, rainfall in St. Louis ranges from 2.2 - 4.7 inches per month. May is typically the wettest month, when rainfall can reach 4.7 in. February is typically the driest time to visit St. Louis when rainfall is around 2.2 in.

Temperature in St. Louis by month

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

If weather is an important factor for your trip to St. Louis, 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 80.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 32.0 F).

Reviews of airlines servicing St. Louis

Get insights into the airlines that provide service to St. Louis. 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 St. Louis. Reviews last updated January 21, 2025.
See what other customers who have flown with American Airlines, Frontier and Delta from Key Largo to St. Louis have to say. In addition to providing an overall rating, users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.1
Very good
4,662 reviews

Food

7.2

Boarding

8.2

Overall

8.1

Crew

8.7

Entertainment

7.7

Comfort

8.1

Reviews

1 / 10

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

Southwest
8.1
Very good
4,662 reviews
Southwest
8.1
Very good
4,662 reviews

Food

7.2

Boarding

8.2

Overall

8.1

Crew

8.7

Entertainment

7.7

Comfort

8.1

Reviews

1 / 10

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

Alaska Airlines
8.0
Very good
9,706 reviews
Southwest
8.1
Very good
4,662 reviews

Food

7.2

Boarding

8.2

Overall

8.1

Crew

8.7

Entertainment

7.7

Comfort

8.1

Reviews

1 / 10

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

Delta
8.0
Very good
8,521 reviews
Southwest
8.1
Very good
4,662 reviews

Food

7.2

Boarding

8.2

Overall

8.1

Crew

8.7

Entertainment

7.7

Comfort

8.1

Reviews

1 / 10

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

United Airlines
7.4
Good
8,985 reviews
Southwest
8.1
Very good
4,662 reviews

Food

7.2

Boarding

8.2

Overall

8.1

Crew

8.7

Entertainment

7.7

Comfort

8.1

Reviews

1 / 10

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

American Airlines
7.2
Good
10,000 reviews
Southwest
8.1
Very good
4,662 reviews

Food

7.2

Boarding

8.2

Overall

8.1

Crew

8.7

Entertainment

7.7

Comfort

8.1

Reviews

1 / 10

We BARELY made the connection and when we got onboard we were treated like disobedient children who should have arrived earlier because we had to ask other passengers to move so we could sit with our kids. The flight attendants on the first flight were nice but the second one, they were snippy and fairly rude.

Related info for your journey

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

    If you book a flight to St. Louis from Key Largo, you will be flying to Lambert-St Louis, which is the city’s only airport. Lambert-St Louis (STL) is located 12.7 mi from the center of St. Louis. There are 5 flights from Key Largo to Lambert-St Louis per day from 5 different airlines.

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

    Flights from Key Largo to Lambert-St Louis have been viewed 3 times in the past calendar month.

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

    To fly one-way, consider booking your trip with Frontier, which is currently one of the cheapest options available, starting at $62. Southwest flights start at $119 while deals on Spirit Airlines start at $123 one-way.

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

    Before booking your flight to St. Louis from Key Largo, check out the most reliable airlines to get you to your destination on time: Finnair (84%), American Airlines (82%), Envoy Air( 81%).

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

    Looking at all options, your cheapest flight can be booked for $159. While the most popular route (Miami - Lambert-St Louis) can be booked for $206 on average our data indicates $367 when flying from Key Largo to St. Louis.

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

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

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

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

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

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

    Currently, August is the cheapest month in which you can book a flight from Key Largo to St. Louis (average of $311). Flying from Key Largo to St. Louis in March is currently the most expensive (average of $356). 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
Fenton
Fairview Heights
Maryland Heights
Collinsville
Wentzville
Eureka
St. Peters
Festus
Alton
Farmington
Chesterfield

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Top 5 airlines flying from Key Largo to St. Louis

Discover the top 5 airlines that operate flights from Key Largo to St. Louis. 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 21, 2025.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$87Average$150FlexibilityNo cancel feeOn-time65%
FrontierCheapest$128Average$248FlexibilityNo cancel feeOn-time62%
DeltaCheapest$199Average$382FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$209Average$352FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$209Average$385FlexibilityNo cancel feeOn-time63%
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