$81+ 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 7/30. Fares are subject to change and may not be available on all flights or dates of travel.
STL — MIA
Jul 31 — Aug 71
Round-trip
1 adult, Economy
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Find cheap flights from St. Louis to Key Largo 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 Lambert-St Louis to Key Largo are usually found in September or October, booked 84 days in advance, depart on a Saturday or Sunday and return on a Thursday
Cheap flight deals from St. Louis to Key Largo
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Cheapest flights from St. Louis to Key LargoExplore 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 July 1, 2026.
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 July 1, 2026.
This Kiwi.com deal was found by Cheapflights users on 6/29. 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 7/244:57 pm
STL
- MIA
1 stop19h 56m
Frontier
Sun 8/28:30 am
MIA
- STL
1 stop10h 07m
Frontier
Deal found 6/29![Frontier logo]()
$275
This Frontier deal was found by Cheapflights users on 6/27. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/1610:35 am
STL
- MIA
1 stop6h 47m
Frontier
Tue 10/207:20 am
MIA
- STL
1 stop12h 55m
Frontier
Deal found 6/27![Frontier logo]()
$276
This Kiwi.com deal was found by Cheapflights users on 6/28. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/56:45 pm
STL
- MIA
2 stops17h 47m
Frontier
Sat 9/1210:09 pm
MIA
- STL
1 stop12h 31m
Frontier
Deal found 6/28![Frontier logo]()
$277
This Kiwi.com deal was found by Cheapflights users on 6/28. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 7/196:34 pm
STL
- MIA
1 stop18h 19m
Frontier
Sun 7/2610:15 pm
MIA
- STL
2 stops44h 22m
Frontier
Deal found 6/28![Frontier logo]()
$278
This Southwest deal was found by Cheapflights users on 6/28. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 7/252:10 pm
STL
- MIA
1 stop7h 35m
Southwest
Mon 7/277:15 am
MIA
- STL
Nonstop2h 50m
Southwest
Deal found 6/28![Southwest logo]()
$279
This CheapOair deal was found by Cheapflights users on 6/28. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/74:57 pm
STL
- MIA
1 stop5h 09m
Frontier
Sun 8/910:15 pm
MIA
- STL
1 stop21h 00m
Frontier
Deal found 6/28![Frontier logo]()
$280
This American Airlines deal was found by Cheapflights users on 6/25. 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 11/245:21 am
STL
- MIA
Nonstop2h 48m
American Airlines
Tue 12/18:28 pm
MIA
- STL
Nonstop3h 04m
American Airlines
Deal found 6/25![American Airlines logo]()
$281
This Kiwi.com deal was found by Cheapflights users on 6/30. 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 7/196:34 pm
STL
- MIA
1 stop18h 19m
Frontier
Fri 7/245:28 pm
MIA
- STL
1 stop16h 29m
Frontier
Deal found 6/30![Frontier logo]()
$282
This Kiwi.com deal was found by Cheapflights users on 6/30. 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 7/196:34 pm
STL
- MIA
1 stop18h 19m
Frontier
Mon 8/106:42 pm
MIA
- STL
1 stop23h 55m
Frontier
Deal found 6/30![Frontier logo]()
$283
This Frontier deal was found by Cheapflights users on 6/28. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/174:57 pm
STL
- MIA
1 stop5h 08m
Frontier
Sat 7/256:50 am
MIA
- STL
1 stop9h 06m
Frontier
Deal found 6/28![Frontier logo]()
$284
This Kiwi.com deal was found by Cheapflights users on 6/28. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/228:08 pm
STL
- MIA
2 stops16h 45m
Frontier
Fri 7/315:28 pm
MIA
- STL
1 stop16h 29m
Frontier
Deal found 6/28![Frontier logo]()
$285
This Frontier deal was found by Cheapflights users on 6/28. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/228:08 pm
STL
- MIA
1 stop8h 43m
Frontier
Sun 8/26:00 am
MIA
- STL
1 stop14h 23m
Frontier
Deal found 6/28![Frontier logo]()
$286
Best flights from St. Louis to Key LargoDiscover carefully curated flight deals from St. Louis to Key Largo that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated July 1, 2026.
Discover carefully curated flight deals from St. Louis to Key Largo that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated July 1, 2026.
This Delta deal was found by Cheapflights users on 6/26. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/166:00 am
STL
- MIA
1 stop6h 05m
Delta
Wed 9/231:12 pm
MIA
- STL
1 stop8h 23m
Delta
Deal found 6/26![Delta logo]()
$289
This Southwest deal was found by Cheapflights users on 6/30. 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 7/2112:45 pm
STL
- MIA
Nonstop2h 40m
Southwest
Tue 7/287:40 am
MIA
- STL
Nonstop2h 50m
Southwest
Deal found 6/30![Southwest logo]()
$297
This Southwest deal was found by Cheapflights users on 6/26. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/16:30 am
STL
- MIA
2 stops8h 00m
Southwest
Tue 9/87:10 am
MIA
- STL
2 stops6h 00m
Southwest
Deal found 6/26![Southwest logo]()
$299
This Southwest deal was found by Cheapflights users on 6/27. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 7/2510:20 am
STL
- MIA
2 stops10h 50m
Southwest
Sat 8/16:10 am
MIA
- STL
2 stops10h 10m
Southwest
Deal found 6/27![Southwest logo]()
$311
This Southwest deal was found by Cheapflights users on 6/27. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 7/2012:45 pm
STL
- MIA
Nonstop2h 40m
Southwest
Fri 7/247:15 am
MIA
- STL
Nonstop2h 50m
Southwest
Deal found 6/27![Southwest logo]()
$313
This Southwest deal was found by Cheapflights users on 6/28. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/197:50 am
STL
- MIA
2 stops10h 25m
Southwest
Tue 9/299:15 am
MIA
- STL
2 stops9h 40m
Southwest
Deal found 6/28![Southwest logo]()
$333
This Southwest deal was found by Cheapflights users on 6/26. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/1712:30 pm
STL
- MIA
Nonstop2h 40m
Southwest
Fri 8/214:50 pm
MIA
- STL
1 stop6h 35m
Southwest
Deal found 6/26![Southwest logo]()
$339
This Southwest deal was found by Cheapflights users on 6/26. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/2310:45 am
STL
- MIA
2 stops8h 25m
Southwest
Mon 9/284:50 pm
MIA
- STL
2 stops6h 15m
Southwest
Deal found 6/26![Southwest logo]()
$344
This Southwest deal was found by Cheapflights users on 6/29. 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.
Thu 7/2312:45 pm
STL
- MIA
Nonstop2h 40m
Southwest
Mon 7/277:15 am
MIA
- STL
Nonstop2h 50m
Southwest
Deal found 6/29![Southwest logo]()
$359
This Southwest deal was found by Cheapflights users on 6/28. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/125:45 am
STL
- MIA
2 stops9h 30m
Southwest
Fri 9/184:50 pm
MIA
- STL
2 stops6h 15m
Southwest
Deal found 6/28![Southwest logo]()
$359
This Southwest deal was found by Cheapflights users on 6/29. 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 7/2510:20 am
STL
- MIA
2 stops10h 50m
Southwest
Mon 7/275:25 am
MIA
- STL
2 stops7h 45m
Southwest
Deal found 6/29![Southwest logo]()
$394
This Southwest deal was found by Cheapflights users on 6/28. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 7/261:05 pm
STL
- MIA
Nonstop2h 40m
Southwest
Fri 7/317:15 am
MIA
- STL
Nonstop2h 50m
Southwest
Deal found 6/28![Southwest logo]()
$419
Last-minute flights from St. Louis to Key LargoDiscover last-minute flight deals from St. Louis to Key Largo. Data last updated July 1, 2026 and is based on user searches.
Discover last-minute flight deals from St. Louis to Key Largo. Data last updated July 1, 2026 and is based on user searches.
This Super.com deal was found by Cheapflights users on 6/28. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 7/58:08 pm
STL
- MIA
1 stop8h 43m
Frontier
Tue 7/1411:19 am
MIA
- STL
1 stop7h 18m
Frontier
Deal found 6/28![Frontier logo]()
$314
This Frontier deal was found by Cheapflights users on 6/28. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 7/64:57 pm
STL
- MIA
1 stop5h 08m
Frontier
Sat 7/116:00 am
MIA
- STL
1 stop14h 23m
Frontier
Deal found 6/28![Frontier logo]()
$348
This Expedia deal was found by Cheapflights users on 6/28. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/78:08 pm
STL
- MIA
1 stop8h 43m
Frontier
Tue 7/1410:15 pm
MIA
- STL
1 stop20h 50m
Frontier
Deal found 6/28![Frontier logo]()
$304
This Kiwi.com deal was found by Cheapflights users on 6/25. 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 7/84:57 pm
STL
- MIA
1 stop29h 08m
Frontier
Sun 7/1211:19 am
MIA
- STL
1 stop7h 18m
Frontier
Deal found 6/25![Frontier logo]()
$296
This Frontier deal was found by Cheapflights users on 6/28. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/84:57 pm
STL
- MIA
1 stop5h 08m
Frontier
Mon 7/206:00 am
MIA
- STL
1 stop14h 23m
Frontier
Deal found 6/28![Frontier logo]()
$303
This Kiwi.com deal was found by Cheapflights users on 6/25. 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 7/84:57 pm
STL
- MIA
1 stop29h 08m
Frontier
Fri 7/108:30 am
MIA
- STL
2 stops11h 53m
Frontier
Deal found 6/25![Frontier logo]()
$330
This Trip.com deal was found by Cheapflights users on 6/26. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/98:08 pm
STL
- MIA
1 stop8h 43m
Frontier
Sat 7/116:50 am
MIA
- STL
1 stop9h 06m
Frontier
Deal found 6/26![Frontier logo]()
$318
This Frontier deal was found by Cheapflights users on 6/26. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/108:08 pm
STL
- MIA
1 stop8h 43m
Frontier
Sat 7/186:00 am
MIA
- STL
1 stop14h 23m
Frontier
Deal found 6/26![Frontier logo]()
$284
This Frontier deal was found by Cheapflights users on 6/26. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/108:08 pm
STL
- MIA
1 stop8h 43m
Frontier
Mon 7/136:00 am
MIA
- STL
1 stop14h 23m
Frontier
Deal found 6/26![Frontier logo]()
$310
One-way flights from St. Louis to Key LargoSearch for one-way flight options from St. Louis to Key Largo. Find affordable one-way fares based on user searches. Data last updated July 1, 2026.
Search for one-way flight options from St. Louis to Key Largo. Find affordable one-way fares based on user searches. Data last updated July 1, 2026.
This Trip.com deal was found by Cheapflights users on 6/28. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/306:34 pm
STL
- MIA
1 stop27h 31m
Frontier
Deal found 6/28![Frontier logo]()
$81
This Trip.com deal was found by Cheapflights users on 6/29. 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.
Thu 8/136:34 pm
STL
- MIA
1 stop18h 19m
Frontier
Deal found 6/29![Frontier logo]()
$83
This Kiwi.com deal was found by Cheapflights users on 6/27. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 8/96:34 pm
STL
- MIA
1 stop18h 19m
Frontier
Deal found 6/27![Frontier logo]()
$84
This Kiwi.com deal was found by Cheapflights users on 6/27. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/216:34 pm
STL
- MIA
1 stop20h 59m
Frontier
Deal found 6/27![Frontier logo]()
$85
This Kiwi.com deal was found by Cheapflights users on 6/30. 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 8/26:34 pm
STL
- MIA
1 stop18h 19m
Frontier
Deal found 6/30![Frontier logo]()
$87
This Kiwi.com deal was found by Cheapflights users on 6/30. 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.
Mon 7/274:57 pm
STL
- MIA
1 stop22h 36m
Frontier
Deal found 6/30![Frontier logo]()
$88
This Kiwi.com deal was found by Cheapflights users on 6/27. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/224:57 pm
STL
- MIA
1 stop29h 08m
Frontier
Deal found 6/27![Frontier logo]()
$89
This Kiwi.com deal was found by Cheapflights users on 6/26. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/1010:35 am
STL
- MIA
1 stop9h 29m
Frontier
Deal found 6/26![Frontier logo]()
$93
This iWofly deal was found by Cheapflights users on 6/27. 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 iWofly is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/117:03 pm
STL
- MIA
1 stop10h 27m
Frontier
Deal found 6/27![Frontier logo]()
$103
This deal was found by Cheapflights users on 6/28. 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 is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/54:57 pm
STL
- MIA
1 stop5h 09m
Frontier
Deal found 6/28![Frontier logo]()
$105
This Kiwi.com deal was found by Cheapflights users on 6/30. 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 8/255:27 pm
STL
- MIA
1 stop19h 45m
Frontier
Deal found 6/30![Frontier logo]()
$110
This Kiwi.com deal was found by Cheapflights users on 6/28. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 7/266:34 pm
STL
- MIA
1 stop18h 19m
Frontier
Deal found 6/28![Frontier logo]()
$111
Find 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 July 1, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $275 (Kiwi.com) |
One-way from | $81 (Trip.com) |
Popular in | June |
Cheapest in | September |
Average price | $430 |
Cheapflights Fare Finder
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 July 1, 2026.
Use the filters below to find and compare flights from St. Louis to Key Largo that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
St. LouisMiami
STL - MIA
STLMIA
Lambert-St Louis
Wed 9/16
6:00 am-1:05 pm
1 stop6h 05m
Miami
Wed 9/23
1:12 pm-8:35 pm
1 stop8h 23m
$289
Quickest round-trip
St. LouisMiami
STL - MIA
STLMIA
Lambert-St Louis
Tue 7/21
12:45 pm-4:25 pm
Nonstop2h 40m
Miami
Tue 7/28
7:40 am-9:30 am
Nonstop2h 50m
$297
St. LouisMiami
STL - MIA
STLMIA
Lambert-St Louis
Tue 9/1
6:30 am-3:30 pm
2 stops8h 00m
Miami
Tue 9/8
7:10 am-12:10 pm
2 stops6h 00m
$299
St. LouisMiami
STL - MIA
STLMIA
Lambert-St Louis
Sat 7/25
10:20 am-10:10 pm
2 stops10h 50m
Miami
Sat 8/1
6:10 am-3:20 pm
2 stops10h 10m
$311
St. LouisMiami
STL - MIA
STLMIA
Lambert-St Louis
Mon 7/20
12:45 pm-4:25 pm
Nonstop2h 40m
Miami
Fri 7/24
7:15 am-9:05 am
Nonstop2h 50m
$313
St. LouisMiami
STL - MIA
STLMIA
Lambert-St Louis
Sat 9/19
7:50 am-7:15 pm
2 stops10h 25m
Miami
Tue 9/29
9:15 am-5:55 pm
2 stops9h 40m
$333
St. LouisMiami
STL - MIA
STLMIA
Lambert-St Louis
Mon 8/17
12:30 pm-4:10 pm
Nonstop2h 40m
Miami
Fri 8/21
4:50 pm-10:25 pm
1 stop6h 35m
$339
St. LouisMiami
STL - MIA
STLMIA
Lambert-St Louis
Wed 9/23
10:45 am-8:10 pm
2 stops8h 25m
Miami
Mon 9/28
4:50 pm-10:05 pm
2 stops6h 15m
$344
St. LouisMiami
STL - MIA
STLMIA
Lambert-St Louis
Thu 7/23
12:45 pm-4:25 pm
Nonstop2h 40m
Miami
Mon 7/27
7:15 am-9:05 am
Nonstop2h 50m
$359
St. LouisMiami
STL - MIA
STLMIA
Lambert-St Louis
Sat 9/12
5:45 am-4:15 pm
2 stops9h 30m
Miami
Fri 9/18
4:50 pm-10:05 pm
2 stops6h 15m
$359
Showing 1-10 of 23 resultsSorted by cheapest first
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.
STL-MIA
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 St. Louis to Key Largo
STL-KE9
STL-MIA
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 July 1, 2026.
It’s optimal to fly from St. Louis to Key Largo in the evening. By choosing this option you can save up to 14% on the cost of your flight, compared to a flight in the afternoon.
How much does it cost to fly round-trip from St. Louis to Key Largo?
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 June 27, 2026.
Travelers seeking maximum savings on their St. Louis to Key Largo flight should consider departing on Tuesday at noon when fares are most often at their lowest. Tuesday evenings flights should be avoided if possible as fares are typically the most expensive at this time.
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 July 1, 2026.
Peruse reviews from past customers who have flown with Southwest,Delta, andUnited Airlines from St. Louis to Key Largo to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Overall
7.9
Crew
8.6
Entertainment
7.5
Food
7.0
Boarding
8.1
Comfort
8.0
Reviews
1 / 20
6.0
GoodScott,Feb 2026
HOU - FLL
Overall
7.9
Crew
8.6
Entertainment
7.5
Food
7.0
Boarding
8.1
Comfort
8.0
Reviews
1 / 20
6.0
GoodScott,Feb 2026
HOU - FLL
Overall
7.9
Crew
8.6
Entertainment
7.5
Food
7.0
Boarding
8.1
Comfort
8.0
Reviews
1 / 20
6.0
GoodScott,Feb 2026
HOU - FLL
Overall
7.9
Crew
8.6
Entertainment
7.5
Food
7.0
Boarding
8.1
Comfort
8.0
Reviews
1 / 20
6.0
GoodScott,Feb 2026
HOU - FLL
Overall
7.9
Crew
8.6
Entertainment
7.5
Food
7.0
Boarding
8.1
Comfort
8.0
Reviews
1 / 20
6.0
GoodScott,Feb 2026
HOU - FLL
Overall
7.9
Crew
8.6
Entertainment
7.5
Food
7.0
Boarding
8.1
Comfort
8.0
Reviews
1 / 20
6.0
GoodScott,Feb 2026
HOU - FLL
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.
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Alternative routes for St. Louis to Key Largo
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Complete your trip
Complete your trip to Key Largo by adding a car rental and/or hotel reservation to your travel itinerary.
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St. Louis and Key Largo flights
Browse other St. Louis and Key Largo flight options. Last updated on July 1, 2026.
Other flights from St. Louis
Browse through other flights departing from St. Louis. Flights are based on user searches made on Cheapflights and were last updated on July 1, 2026.
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St. Louis to Key Largo flights
Consider these flights traveling from St. Louis to Key Largo.
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 July 1, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$126 | Average$220 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$150 | Average$456 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$194 | Average$413 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$196 | Average$404 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$220 | Average$408 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$245 | Average$454 | FlexibilityNo cancel fee | On-time63% |