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Cheap flights from St. Louis to Key West from $140

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from St. Louis to Key West departing on 10/15. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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0 bags

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Find the cheapest flights from St. Louis to Key West

Cheap round-trip flights

Delta Logo
1:26 pm - 8:07 pmSTL-EYW
5h 41m1 stop
Delta Logo
7:40 am - 12:35 pmEYW-STL
5h 55m1 stop
$223Delta
Find Deal
Wed, Oct 1 - Tue, Oct 7
American Airlines Logo
8:49 am - 7:22 pmSTL-EYW
9h 33m2 stops
American Airlines Logo
1:38 pm - 9:26 pmEYW-STL
8h 48m1 stop
$228American Airlines
Find Deal
Wed, Oct 22 - Tue, Oct 28
American Airlines Logo
8:49 am - 7:22 pmSTL-EYW
9h 33m2 stops
American Airlines Logo
11:22 am - 9:26 pmEYW-STL
11h 04m2 stops
$233American Airlines
Find Deal
Wed, Oct 22 - Tue, Oct 28
Delta Logo
1:26 pm - 8:12 pmSTL-EYW
5h 46m1 stop
Delta Logo
6:20 pm - 10:02 pmEYW-STL
4h 42m1 stop
$241Delta
Find Deal
Wed, Aug 27 - Wed, Sep 3
American Airlines Logo
7:01 am - 7:07 pmSTL-EYW
11h 06m2 stops
American Airlines Logo
7:31 pm - 11:59 pmEYW-STL
5h 28m1 stop
$246American Airlines
Find Deal
Wed, Aug 27 - Wed, Sep 3
American Airlines Logo
7:01 am - 7:07 pmSTL-EYW
11h 06m2 stops
American Airlines Logo
11:25 am - 8:15 pmEYW-STL
9h 50m2 stops
$251American Airlines
Find Deal
Wed, Aug 27 - Wed, Sep 3
American Airlines Logo
8:54 am - 7:29 pmSTL-EYW
9h 35m2 stops
American Airlines Logo
6:33 pm - 11:07 pmEYW-STL
5h 34m1 stop
$256American Airlines
Find Deal
Sat, Nov 8 - Tue, Nov 11
Delta Logo
6:00 am - 1:02 pmSTL-EYW
6h 02m1 stop
Delta Logo
7:40 am - 12:35 pmEYW-STL
5h 55m1 stop
$259Delta
Find Deal
Wed, Oct 29 - Tue, Nov 4
American Airlines Logo
8:49 am - 4:18 pmSTL-EYW
6h 29m1 stop
American Airlines Logo
1:38 pm - 9:26 pmEYW-STL
8h 48m1 stop
$266American Airlines
Find Deal
Wed, Oct 22 - Tue, Oct 28
American Airlines Logo
7:01 am - 6:59 pmSTL-EYW
10h 58m2 stops
American Airlines Logo
7:31 pm - 11:59 pmEYW-STL
5h 28m1 stop
$271American Airlines
Find Deal
Sat, Sep 20 - Sat, Sep 27

Delta flights from St. Louis to Key West

Our best Delta deals on St. Louis to Key West flight tickets
Delta
Oct 1
STL1:26 pmLambert-St Louis
5h 41m
1 stop
EYW8:07 pmKey West
Oct 7
EYW7:40 amKey West
5h 55m
1 stop
STL12:35 pmLambert-St Louis
$223
Find similar
Delta
Aug 27
STL1:26 pmLambert-St Louis
5h 46m
1 stop
EYW8:12 pmKey West
Sep 3
EYW6:20 pmKey West
4h 42m
1 stop
STL10:02 pmLambert-St Louis
$241
Find similar
Delta
Oct 29
STL6:00 amLambert-St Louis
6h 02m
1 stop
EYW1:02 pmKey West
Nov 4
EYW7:40 amKey West
5h 55m
1 stop
STL12:35 pmLambert-St Louis
$259
Find similar

American Airlines flights from St. Louis to Key West

Our best American Airlines deals on St. Louis to Key West flight tickets
American Airlines
Oct 22
STL8:49 amLambert-St Louis
9h 33m
2 stops
EYW7:22 pmKey West
Oct 28
EYW1:38 pmKey West
8h 48m
1 stop
STL9:26 pmLambert-St Louis
$228
Find similar
American Airlines
Oct 22
STL8:49 amLambert-St Louis
9h 33m
2 stops
EYW7:22 pmKey West
Oct 28
EYW11:22 amKey West
11h 04m
2 stops
STL9:26 pmLambert-St Louis
$233
Find similar
American Airlines
Aug 27
STL7:01 amLambert-St Louis
11h 06m
2 stops
EYW7:07 pmKey West
Sep 3
EYW7:31 pmKey West
5h 28m
1 stop
STL11:59 pmLambert-St Louis
$246
Find similar

momondo Fare Finder

 
Customize your flight search to find flights from St. Louis to Key West 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, momondo users made 832,500 searches. Data last updated August 2, 2025.
Use the filters below to find and compare flights from St. Louis to Key West that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

St. LouisKey West

STL - EYW

STLEYW

Lambert-St Louis

Wed 10/1

1:26 pm-8:07 pm

1 stop5h 41m

Key West

Tue 10/7

7:40 am-12:35 pm

1 stop5h 55m

$223

St. LouisKey West

STL - EYW

STLEYW

Lambert-St Louis

Wed 10/22

8:49 am-7:22 pm

2 stops9h 33m

Key West

Tue 10/28

1:38 pm-9:26 pm

1 stop8h 48m

$228

St. LouisKey West

STL - EYW

STLEYW

Lambert-St Louis

Wed 10/22

8:49 am-7:22 pm

2 stops9h 33m

Key West

Tue 10/28

11:22 am-9:26 pm

2 stops11h 04m

$233

St. LouisKey West

STL - EYW

STLEYW

Lambert-St Louis

Wed 8/27

1:26 pm-8:12 pm

1 stop5h 46m

Key West

Wed 9/3

6:20 pm-10:02 pm

1 stop4h 42m

$241

St. LouisKey West

STL - EYW

STLEYW

Lambert-St Louis

Wed 8/27

7:01 am-7:07 pm

2 stops11h 06m

Key West

Wed 9/3

7:31 pm-11:59 pm

1 stop5h 28m

$246

St. LouisKey West

STL - EYW

STLEYW

Lambert-St Louis

Wed 8/27

7:01 am-7:07 pm

2 stops11h 06m

Key West

Wed 9/3

11:25 am-8:15 pm

2 stops9h 50m

$251

St. LouisKey West

STL - EYW

STLEYW

Lambert-St Louis

Sat 11/8

8:54 am-7:29 pm

2 stops9h 35m

Key West

Tue 11/11

6:33 pm-11:07 pm

1 stop5h 34m

$256

St. LouisKey West

STL - EYW

STLEYW

Lambert-St Louis

Wed 10/29

6:00 am-1:02 pm

1 stop6h 02m

Key West

Tue 11/4

7:40 am-12:35 pm

1 stop5h 55m

$259

St. LouisKey West

STL - EYW

STLEYW

Lambert-St Louis

Wed 10/22

8:49 am-4:18 pm

1 stop6h 29m

Key West

Tue 10/28

1:38 pm-9:26 pm

1 stop8h 48m

$266

St. LouisKey West

STL - EYW

STLEYW

Lambert-St Louis

Sat 9/20

7:01 am-6:59 pm

2 stops10h 58m

Key West

Sat 9/27

7:31 pm-11:59 pm

1 stop5h 28m

$271

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first
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See travel insights to Key West from

How to get the cheapest flight ticket from St. Louis to Key West

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

What is the cheapest month to fly to Key West?

In general, December is the cheapest month to fly from St. Louis to Key West. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $378. If you are unable to visit Key West during the month of December, then departing from St. Louis during the month August is also very affordable. Most momondo users find prices during this month for around $381.

What is the cheapest day to depart on your flight to Key West?

On average, the least expensive day to fly to Key West from St. Louis is on a Friday. momondo users have found tickets for Friday departures for as low as $376. However, this price may fluctuate depending on the airline, the season, and holidays. When flying out on a Sunday, the most expensive travel day of the week, you can expect to see flight prices from St. Louis to Key West for around $557.

What is the cheapest time of day to depart on your flight to Key West?

According to our data, the cheapest time of day to fly to Key West is at noon. momondo users have found flights departing from St. Louis to Key West at noon for as low as $394. Keep in mind that these prices may fluctuate based on what airline you choose and the time of year you plan to travel. Flights to Key West are more costly in the afternoon, with an average ticket price of $470. Departure times in the afternoon fall within the peak daily travel times, which is why tickets can be more expensive.

How far in advance should I book a flight to Key West?

You are more likely to see cheaper flights to Key West from St. Louis when booking weeks ahead of your departure date. In general, you can expect to find flights to Key West for around $435 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Key West from St. Louis for as low as $335 on momondo.

When to book flights from St. Louis to Key West

Are you open to changing your travel dates? Check out the ideal times to fly from St. Louis to Key West according to our flight data. Find out which month and days have the cheapest flights.
Estimated round-trip price

Cheap St. Louis to Key West (STL to EYW) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from St. Louis to Key West

Best Price Found

$140

Fastest flight time

4h 27m

Direct flights

None

Airports in Key West

1 airport
The best one-way flight to Key West from St. Louis in the past 72 hours is $140. The best round-trip flight deal from St. Louis to Key West found on momondo in the last 72 hours is $223.
The fastest flight from St. Louis to Key West takes 4h 27m
There are no direct flights from St. Louis to Key West. Popular non-direct route for this connection is Lambert-St Louis Airport - Key West Airport.
There is 1 airport near Key West: Key West (EYW)
Search flight deals

  • How far is Lambert-St Louis to Key West by plane?

    A flight from Lambert-St Louis to Key West will travel around 1088.7 mi. 4h 27m is a normal flight duration for this route.

  • When did momondo last update prices for flights from Lambert-St Louis Airport to Key West Airport?

    Prices for flights from Lambert-St Louis Airport to Key West Airport are refreshed on a daily basis.

  • How many operators does momondo search for flights from Lambert-St Louis Airport to Key West Airport?

  • How old do you have to be to fly from Lambert-St Louis Airport to Key West Airport?

    Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Lambert-St Louis Airport to Key West Airport.

  • What documentation or ID do you need to fly to Key West Airport?

    The necessary travel and health documents for your Key West Airport trip may vary depending on your travel plans and individual circumstances. Generally, you should have various documents, such as a national ID card or driver's license and a passport that is valid for six months beyond your scheduled arrival date. We recommend seeking advice from your airline or a trusted third party, such as IATA.

  • What is the most popular airline from St. Louis to Key West?

Best airlines flying from St. Louis to Key West

Compare and see reviews for airlines that fly from St. Louis to Key West with momondo
Airline
Rating
Free Cancellation
Price
DeltaPriceFrom $218Free CancellationRating
8.0
7,983 reviews
Search Delta flights
United AirlinesPriceFrom $245Free CancellationRating
7.4
8,904 reviews
Search United Airlines flights
American AirlinesPriceFrom $253Free CancellationRating
7.2
10,000 reviews
Search American Airlines flights

Traveling to a place near Key West?

Book flights to Key West if you plan to visit one of these locations
Big Pine Key
Little Torch Key

Why use momondo?

Why should I use momondo to find a flight deal from St. Louis to Key West?

We help find the flight that best suits your needs, momondo compares prices from hundreds of airlines and travel agents and helps you filter them to find the best flight from St. Louis to Key West for you.

Can I find flights from St. Louis to Key West with flexible booking policies on momondo?

Flights from St. Louis to Key West with flexible booking policies can be found by using the search form above and then selecting our dedicated flexible booking filter, which will highlight only the flights where this policy is applied.

How can momondo help me find flights from St. Louis to Key West?

Once you have performed a search for St. Louis to Key West flights, momondo helps you find the right one by offering useful filters to narrow down your flight selection. Flights can be filtered by multiple factors such as airline, airport and price; but also by other criteria like aircraft type and payment method.

I’m not ready to book a flight from St. Louis to Key West right now. Can momondo alert me if prices change?

Yes. momondo can track prices for St. Louis to Key West flights and alert you when they change. Perform a search to set up the price alert. All that is required is a valid email address.

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