$57+ 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 3/3. Fares are subject to change and may not be available on all flights or dates of travel.
MIA — STL
Mar 9 — Mar 161
1 adult, Economy
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Find cheap flights from Key Largo to St. Louis with Cheapflights
1. Tell us where you want to go
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”2. Select your favorite providers
We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.3. Compare prices and book
Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.Cheapflights Tip: The best prices from Key Largo to Lambert-St Louis are usually found in October or August, booked 62 days in advance, depart on a Thursday or Friday and return on a Sunday
Cheap flight deals from Key Largo to St. Louis
Cheapest
Best
Last-minute
One-way
Cheapest flights from Key Largo to St. LouisExplore 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 February 7, 2026.
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 February 7, 2026.
This Kiwi.com deal was found by Cheapflights users on 2/6. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 2/247:05 am
MIA
- STL
1 stop24h 46m
Multiple Airlines
Sat 2/288:17 pm
STL
- MIA
1 stop13h 11m
Multiple Airlines
Deal found 2/6![Multiple Airlines logo]()
$126
This Kiwi.com deal was found by Cheapflights users on 2/4. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 2/205:05 am
MIA
- STL
1 stop26h 46m
Multiple Airlines
Mon 2/238:22 pm
STL
- MIA
1 stop14h 54m
Multiple Airlines
Deal found 2/4![Multiple Airlines logo]()
$130
This Kiwi.com deal was found by Cheapflights users on 2/5. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 2/205:05 am
MIA
- STL
1 stop26h 46m
Frontier
Sat 2/218:17 pm
STL
- MIA
1 stop13h 11m
Frontier
Deal found 2/5![Frontier logo]()
$132
This Kiwi.com deal was found by Cheapflights users on 2/4. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 2/207:05 am
MIA
- STL
1 stop24h 46m
Multiple Airlines
Sat 2/218:17 pm
STL
- MIA
1 stop13h 11m
Multiple Airlines
Deal found 2/4![Multiple Airlines logo]()
$133
This Kiwi.com deal was found by Cheapflights users on 2/4. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/197:05 am
MIA
- STL
1 stop24h 46m
Multiple Airlines
Mon 2/238:22 pm
STL
- MIA
1 stop14h 54m
Multiple Airlines
Deal found 2/4![Multiple Airlines logo]()
$135
This Kiwi.com deal was found by Cheapflights users on 2/5. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/195:05 am
MIA
- STL
1 stop26h 46m
Frontier
Sat 2/218:17 pm
STL
- MIA
1 stop13h 11m
Frontier
Deal found 2/5![Frontier logo]()
$144
This Kiwi.com deal was found by Cheapflights users on 2/6. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/197:14 pm
MIA
- STL
1 stop12h 37m
Multiple Airlines
Sat 2/218:17 pm
STL
- MIA
1 stop14h 59m
Multiple Airlines
Deal found 2/6![Multiple Airlines logo]()
$145
This Kiwi.com deal was found by Cheapflights users on 2/4. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 2/177:09 pm
MIA
- STL
1 stop12h 42m
Frontier
Wed 2/188:17 pm
STL
- MIA
1 stop27h 25m
Frontier
Deal found 2/4![Frontier logo]()
$147
This Kiwi.com deal was found by Cheapflights users on 2/4. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/197:14 pm
MIA
- STL
1 stop12h 37m
Multiple Airlines
Fri 2/208:20 pm
STL
- MIA
1 stop14h 56m
Multiple Airlines
Deal found 2/4![Multiple Airlines logo]()
$150
This Kiwi.com deal was found by Cheapflights users on 2/4. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 2/177:09 pm
MIA
- STL
1 stop12h 42m
Multiple Airlines
Fri 2/208:20 pm
STL
- MIA
1 stop14h 56m
Multiple Airlines
Deal found 2/4![Multiple Airlines logo]()
$153
This Kiwi.com deal was found by Cheapflights users on 2/4. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/265:05 am
MIA
- STL
1 stop6h 26m
Multiple Airlines
Sun 3/2911:21 am
STL
- MIA
1 stop7h 46m
Multiple Airlines
Deal found 2/4![Multiple Airlines logo]()
$161
Best flights from Key Largo to St. LouisDiscover carefully curated flight deals from Key Largo to St. Louis that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated February 7, 2026.
Discover carefully curated flight deals from Key Largo to St. Louis that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated February 7, 2026.
This Kiwi.com deal was found by Cheapflights users on 2/4. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/197:14 pm
MIA
- STL
1 stop12h 37m
Frontier
Sat 2/218:17 pm
STL
- MIA
1 stop19h 34m
Frontier
Deal found 2/4![Frontier logo]()
$144
This United Airlines deal was found by Cheapflights users on 2/3. 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.
Tue 5/124:52 pm
MIA
- STL
1 stop6h 38m
United Airlines
Wed 5/137:45 am
STL
- MIA
2 stops9h 45m
United Airlines
Deal found 2/3![United Airlines logo]()
$222
This Southwest deal was found by Cheapflights users on 2/3. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/127:00 am
MIA
- STL
2 stops9h 15m
Southwest
Wed 5/1310:25 am
STL
- MIA
2 stops9h 45m
Southwest
Deal found 2/3![Southwest logo]()
$309
This American Airlines deal was found by Cheapflights users on 2/5. 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.
Thu 5/148:15 pm
MIA
- STL
Nonstop3h 09m
American Airlines
Sun 5/1711:06 am
STL
- MIA
Nonstop2h 51m
American Airlines
Deal found 2/5![American Airlines logo]()
$328
This Kiwi.com deal was found by Cheapflights users on 2/5. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 3/85:05 am
MIA
- STL
2 stops29h 44m
Frontier
Wed 3/1111:32 am
STL
- MIA
1 stop12h 15m
Frontier
Deal found 2/5![Frontier logo]()
$208
This Frontier deal was found by Cheapflights users on 2/4. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 3/68:08 pm
MIA
- STL
1 stop14h 41m
Frontier
Mon 3/92:09 pm
STL
- MIA
1 stop9h 38m
Frontier
Deal found 2/4![Frontier logo]()
$248
This Kiwi.com deal was found by Cheapflights users on 2/6. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 3/65:05 am
MIA
- STL
1 stop7h 44m
Frontier
Sun 3/84:51 pm
STL
- MIA
2 stops24h 02m
Frontier
Deal found 2/6![Frontier logo]()
$260
This Southwest deal was found by Cheapflights users on 2/6. 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 2/286:00 am
MIA
- STL
Nonstop3h 05m
Southwest
Mon 3/27:50 am
STL
- MIA
Nonstop2h 40m
Southwest
Deal found 2/6![Southwest logo]()
$335
This Kiwi.com deal was found by Cheapflights users on 2/5. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/197:14 pm
MIA
- STL
1 stop12h 37m
Frontier
Sun 2/223:49 pm
STL
- MIA
2 stops22h 54m
Frontier
Deal found 2/5![Frontier logo]()
$275
This Southwest deal was found by Cheapflights users on 2/3. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 2/286:00 am
MIA
- STL
Nonstop3h 05m
Southwest
Wed 3/48:15 am
STL
- MIA
Nonstop2h 45m
Southwest
Deal found 2/3![Southwest logo]()
$349
Last-minute flights from Key Largo to St. LouisDiscover last-minute flight deals from Key Largo to St. Louis. Data last updated February 7, 2026 and is based on user searches.
Discover last-minute flight deals from Key Largo to St. Louis. Data last updated February 7, 2026 and is based on user searches.
This Kiwi.com deal was found by Cheapflights users on 2/4. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 2/177:09 pm
MIA
- STL
1 stop12h 42m
Frontier
Sat 2/218:17 pm
STL
- MIA
1 stop13h 11m
Frontier
Deal found 2/4![Frontier logo]()
$147
This Kiwi.com deal was found by Cheapflights users on 2/4. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 2/177:09 pm
MIA
- STL
1 stop12h 42m
Multiple Airlines
Fri 2/208:20 pm
STL
- MIA
1 stop14h 56m
Multiple Airlines
Deal found 2/4![Multiple Airlines logo]()
$153
This Kiwi.com deal was found by Cheapflights users on 2/4. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/197:05 am
MIA
- STL
1 stop24h 46m
Multiple Airlines
Mon 2/238:22 pm
STL
- MIA
1 stop14h 54m
Multiple Airlines
Deal found 2/4![Multiple Airlines logo]()
$135
This Kiwi.com deal was found by Cheapflights users on 2/5. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/195:05 am
MIA
- STL
1 stop26h 46m
Frontier
Sat 2/218:17 pm
STL
- MIA
1 stop13h 11m
Frontier
Deal found 2/5![Frontier logo]()
$144
This Kiwi.com deal was found by Cheapflights users on 2/6. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/197:14 pm
MIA
- STL
1 stop12h 37m
Multiple Airlines
Sat 2/218:17 pm
STL
- MIA
1 stop14h 59m
Multiple Airlines
Deal found 2/6![Multiple Airlines logo]()
$145
This Kiwi.com deal was found by Cheapflights users on 2/4. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/197:14 pm
MIA
- STL
1 stop12h 37m
Multiple Airlines
Fri 2/208:20 pm
STL
- MIA
1 stop14h 56m
Multiple Airlines
Deal found 2/4![Multiple Airlines logo]()
$150
This Kiwi.com deal was found by Cheapflights users on 2/4. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 2/205:05 am
MIA
- STL
1 stop26h 46m
Multiple Airlines
Mon 2/238:22 pm
STL
- MIA
1 stop14h 54m
Multiple Airlines
Deal found 2/4![Multiple Airlines logo]()
$130
This Kiwi.com deal was found by Cheapflights users on 2/5. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 2/205:05 am
MIA
- STL
1 stop26h 46m
Frontier
Sat 2/218:17 pm
STL
- MIA
1 stop13h 11m
Frontier
Deal found 2/5![Frontier logo]()
$132
This Kiwi.com deal was found by Cheapflights users on 2/6. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 2/205:05 am
MIA
- STL
1 stop26h 46m
Multiple Airlines
Sat 2/218:17 pm
STL
- MIA
1 stop14h 59m
Multiple Airlines
Deal found 2/6![Multiple Airlines logo]()
$133
This Kiwi.com deal was found by Cheapflights users on 2/6. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 2/247:05 am
MIA
- STL
1 stop24h 46m
Multiple Airlines
Sat 2/288:17 pm
STL
- MIA
1 stop13h 11m
Multiple Airlines
Deal found 2/6![Multiple Airlines logo]()
$126
This Kiwi.com deal was found by Cheapflights users on 2/4. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/265:05 am
MIA
- STL
1 stop6h 26m
Multiple Airlines
Sun 3/2911:21 am
STL
- MIA
1 stop7h 46m
Multiple Airlines
Deal found 2/4![Multiple Airlines logo]()
$161
One-way flights from Key Largo to St. LouisSearch for one-way flight options from Key Largo to St. Louis. Find affordable one-way fares based on user searches. Data last updated February 7, 2026.
Search for one-way flight options from Key Largo to St. Louis. Find affordable one-way fares based on user searches. Data last updated February 7, 2026.
This Trip.com deal was found by Cheapflights users on 2/4. 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.
Tue 3/37:05 am
MIA
- STL
1 stop24h 46m
Multiple Airlines
Deal found 2/4![Multiple Airlines logo]()
$57
This Kiwi.com deal was found by Cheapflights users on 2/4. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/57:09 pm
MIA
- STL
1 stop17h 40m
Frontier
Deal found 2/4![Frontier logo]()
$67
This Kiwi.com deal was found by Cheapflights users on 2/5. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/217:35 am
MIA
- STL
1 stop24h 15m
Multiple Airlines
Deal found 2/5![Multiple Airlines logo]()
$68
This Expedia deal was found by Cheapflights users on 2/4. 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.
Wed 2/255:45 am
MIA
- STL
1 stop11h 08m
Frontier
Deal found 2/4![Frontier logo]()
$70
This Kiwi.com deal was found by Cheapflights users on 2/4. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/512:26 pm
MIA
- STL
1 stop19h 24m
Frontier
Deal found 2/4![Frontier logo]()
$71
This Super.com deal was found by Cheapflights users on 2/5. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/46:25 am
MIA
- STL
1 stop10h 28m
Frontier
Deal found 2/5![Frontier logo]()
$73
This Kiwi.com deal was found by Cheapflights users on 2/4. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 3/15:05 am
MIA
- STL
1 stop26h 46m
Frontier
Deal found 2/4![Frontier logo]()
$76
This Kiwi.com deal was found by Cheapflights users on 2/4. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/177:04 pm
MIA
- STL
1 stop12h 46m
Frontier
Deal found 2/4![Frontier logo]()
$80
This Kiwi.com deal was found by Cheapflights users on 2/4. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/13:12 pm
MIA
- STL
1 stop20h 18m
Multiple Airlines
Deal found 2/4![Multiple Airlines logo]()
$81
This Kiwi.com deal was found by Cheapflights users on 2/6. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/157:04 pm
MIA
- STL
1 stop16h 26m
Frontier
Deal found 2/6![Frontier logo]()
$82
Find flight deals from Key Largo to St. Louis
Keep the following information in mind while searching for Key Largo to St. Louis flight deals. Data was last updated February 7, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $126 (Kiwi.com) |
One-way from | $57 (Trip.com) |
Popular in | February |
Cheapest in | October |
Average price | $489 |
Cheapflights Fare Finder
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 February 7, 2026.
Use the filters below to find and compare flights from Key Largo to St. Louis that are best for you.
Fly from
Key Largo
Fly to
St. Louis
Route
Depart
Return
Price
MiamiSt. Louis
MIA - STL
MIASTL
Miami
Thu 2/19
7:14 pm-6:51 am
1 stop12h 37m
Lambert-St Louis
Sat 2/21
8:17 pm-4:51 pm
1 stop19h 34m
$144
MiamiSt. Louis
MIA - STL
MIASTL
Miami
Sun 3/8
5:05 am-9:49 am
2 stops29h 44m
Lambert-St Louis
Wed 3/11
11:32 am-12:47 am
1 stop12h 15m
$208
MiamiSt. Louis
MIA - STL
MIASTL
Miami
Tue 5/12
4:52 pm-10:30 pm
1 stop6h 38m
Lambert-St Louis
Wed 5/13
7:45 am-6:30 pm
2 stops9h 45m
$222
MiamiSt. Louis
MIA - STL
MIASTL
Miami
Fri 3/6
8:08 pm-9:49 am
1 stop14h 41m
Lambert-St Louis
Mon 3/9
2:09 pm-12:47 am
1 stop9h 38m
$248
MiamiSt. Louis
MIA - STL
MIASTL
Miami
Fri 3/6
5:05 am-11:49 am
1 stop7h 44m
Lambert-St Louis
Sun 3/8
4:51 pm-5:53 pm
2 stops24h 02m
$260
MiamiSt. Louis
MIA - STL
MIASTL
Miami
Thu 2/19
7:14 pm-6:51 am
1 stop12h 37m
Lambert-St Louis
Sun 2/22
3:49 pm-3:43 pm
2 stops22h 54m
$275
MiamiSt. Louis
MIA - STL
MIASTL
Miami
Tue 5/12
7:00 am-3:15 pm
2 stops9h 15m
Lambert-St Louis
Wed 5/13
10:25 am-9:10 pm
2 stops9h 45m
$309
MiamiSt. Louis
MIA - STL
MIASTL
Miami
Thu 5/14
8:15 pm-10:24 pm
Nonstop3h 09m
Lambert-St Louis
Sun 5/17
11:06 am-2:57 pm
Nonstop2h 51m
$328
MiamiSt. Louis
MIA - STL
MIASTL
Miami
Sat 2/28
6:00 am-8:05 am
Nonstop3h 05m
Lambert-St Louis
Mon 3/2
7:50 am-11:30 am
Nonstop2h 40m
$335
MiamiSt. Louis
MIA - STL
MIASTL
Miami
Sat 2/28
6:00 am-8:05 am
Nonstop3h 05m
Lambert-St Louis
Wed 3/4
8:15 am-12:00 pm
Nonstop2h 45m
$349
Showing 1-10 of 21 results
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.
MIA-STL
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 St. Louis
KE9-STL
MIA-STL
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 30, 2026.
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 62 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, March is the cheapest month in which you can book a flight from Key Largo to St. Louis (average of $38). Flying from Key Largo to St. Louis in April is currently the most expensive (average of $152). 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 February 7, 2026.
One of the essential ways to save on airfare from Key Largo to St. Louis is to remain as flexible as possible. Flights that are in the evening tend to be the most expensive. A flight at noon could potentially save you up to 19% on airfare.
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 January 31, 2026.
Travelers seeking maximum savings on their Key Largo to St. Louis flight should consider departing on Wednesday at noon when fares are most often at their lowest. Saturday 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 February 7, 2026.
The most flights from KE9 to STL are scheduled on a Wednesday (8 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (4 on average).
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 February 7, 2026.
See what other customers who have flown with Southwest, Delta, and American Airlines from Key Largo to St. Louis have to say. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Food
7.0
Comfort
8.0
Entertainment
7.5
Boarding
8.1
Overall
8.0
Crew
8.6
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Food
7.0
Comfort
8.0
Entertainment
7.5
Boarding
8.1
Overall
8.0
Crew
8.6
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Food
7.0
Comfort
8.0
Entertainment
7.5
Boarding
8.1
Overall
8.0
Crew
8.6
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Food
7.0
Comfort
8.0
Entertainment
7.5
Boarding
8.1
Overall
8.0
Crew
8.6
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Food
7.0
Comfort
8.0
Entertainment
7.5
Boarding
8.1
Overall
8.0
Crew
8.6
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
Food
7.0
Comfort
8.0
Entertainment
7.5
Boarding
8.1
Overall
8.0
Crew
8.6
Reviews
1 / 20
2.0
MediocreThomas,Dec 2025
SEA - DEN
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.
Traveling to a place near St. Louis?
Book flights to St. Louis if you plan to visit one of these locationsEdwardsville
O'Fallon
Swansea
Fairview Heights
Maryland Heights
Collinsville
Eureka
Glencoe
Chesterfield
Alton
Farmington
Festus
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Alternative routes for Key Largo to St. Louis
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Complete your trip
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Key Largo and St. Louis flights
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Other flights to St. Louis
Explore flights to St. Louis departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on February 7, 2026.
Key Largo to St. Louis flights
Consider these flights traveling from Key Largo to St. Louis.
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 February 7, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$47 | Average$182 | FlexibilityNo cancel fee | On-time65% | |
| Cheapest$102 | Average$244 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$130 | Average$328 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$186 | Average$382 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$211 | Average$384 | FlexibilityNo cancel fee | On-time71% |