$499+ Cheap flights from St. Louis (STL) to Keflavik Intl (KEF)
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 9/24. Fares are subject to change and may not be available on all flights or dates of travel.
STL — KEF
Aug 21 — Aug 281
Round-trip
1 adult, Economy
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Find cheap flights from St. Louis to Keflavik Intl 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
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Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.Cheap flight deals from St. Louis to Keflavik Intl
Cheapest
Best
Last-minute
One-way
Cheapest flights from St. Louis to Keflavik IntlExplore the most affordable flight options available from St. Louis to Keflavik Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 22, 2026.
Explore the most affordable flight options available from St. Louis to Keflavik Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 22, 2026.
This Kiwi.com deal was found by Cheapflights users on 7/19. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 8/236:17 pm
STL
- KEF
2 stops30h 43m
Multiple Airlines
Mon 8/3110:45 am
KEF
- STL
1 stop13h 28m
Multiple Airlines
Deal found 7/19![Multiple Airlines logo]()
$783
This United Airlines deal was found by Cheapflights users on 7/21. 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.
Mon 9/217:00 am
STL
- KEF
1 stop19h 00m
United Airlines
Wed 9/309:15 am
KEF
- STL
2 stops35h 28m
United Airlines
Deal found 7/21![United Airlines logo]()
$784
This FlightHub deal was found by Cheapflights users on 7/18. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/216:53 pm
STL
- KEF
2 stops32h 02m
Air Canada
Wed 9/309:15 am
KEF
- STL
2 stops35h 28m
Air Canada
Deal found 7/18![Air Canada logo]()
$788
This United Airlines deal was found by Cheapflights users on 7/21. 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 9/228:50 am
STL
- KEF
2 stops18h 05m
United Airlines
Tue 9/2910:00 am
KEF
- STL
2 stops30h 22m
United Airlines
Deal found 7/21![United Airlines logo]()
$793
This Air France deal was found by Cheapflights users on 7/19. 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 Air France is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/213:52 pm
STL
- KEF
1 stop10h 08m
Multiple Airlines
Wed 9/309:30 am
KEF
- STL
1 stop18h 46m
Multiple Airlines
Deal found 7/19![Multiple Airlines logo]()
$805
This Icelandair deal was found by Cheapflights users on 7/20. 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 Icelandair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/146:25 am
STL
- KEF
1 stop18h 05m
Multiple Airlines
Wed 11/254:45 pm
KEF
- STL
1 stop20h 20m
Multiple Airlines
Deal found 7/20![Multiple Airlines logo]()
$843
Best flights from St. Louis to Keflavik IntlDiscover carefully curated flight deals from St. Louis to Keflavik Intl that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated July 22, 2026.
Discover carefully curated flight deals from St. Louis to Keflavik Intl that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated July 22, 2026.
This United Airlines deal was found by Cheapflights users on 7/21. 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.
Mon 9/217:00 am
STL
- KEF
1 stop19h 00m
United Airlines
Wed 9/309:15 am
KEF
- STL
2 stops35h 28m
United Airlines
Deal found 7/21![United Airlines logo]()
$784
This Icelandair deal was found by Cheapflights users on 7/18. 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 Icelandair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/101:45 pm
STL
- KEF
1 stop11h 50m
Multiple Airlines
Sat 10/177:50 pm
KEF
- STL
1 stop18h 30m
Multiple Airlines
Deal found 7/18![Multiple Airlines logo]()
$863
This United Airlines deal was found by Cheapflights users on 7/21. 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 9/2212:10 pm
STL
- KEF
1 stop14h 45m
United Airlines
Tue 9/2910:00 am
KEF
- STL
2 stops30h 22m
United Airlines
Deal found 7/21![United Airlines logo]()
$788
This Icelandair deal was found by Cheapflights users on 7/17. 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 Icelandair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/112:20 pm
STL
- KEF
1 stop12h 40m
Multiple Airlines
Tue 9/84:45 pm
KEF
- STL
1 stop21h 45m
Multiple Airlines
Deal found 7/17![Multiple Airlines logo]()
$899
This United Airlines deal was found by Cheapflights users on 7/17. 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.
Fri 10/98:55 am
STL
- KEF
1 stop18h 50m
United Airlines
Sat 10/1710:00 am
KEF
- STL
2 stops34h 43m
United Airlines
Deal found 7/17![United Airlines logo]()
$899
This Icelandair deal was found by Cheapflights users on 7/19. 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 Icelandair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/204:20 pm
STL
- KEF
1 stop11h 20m
Multiple Airlines
Wed 9/305:00 pm
KEF
- STL
1 stop19h 45m
Multiple Airlines
Deal found 7/19![Multiple Airlines logo]()
$907
Last-minute flights from St. Louis to Keflavik IntlDiscover last-minute flight deals from St. Louis to Keflavik Intl. Data last updated July 22, 2026 and is based on user searches.
Discover last-minute flight deals from St. Louis to Keflavik Intl. Data last updated July 22, 2026 and is based on user searches.
This Icelandair deal was found by Cheapflights users on 7/21. 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 Icelandair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/134:15 pm
STL
- KEF
1 stop11h 55m
Multiple Airlines
Sat 8/224:45 pm
KEF
- STL
1 stop20h 25m
Multiple Airlines
Deal found 7/21![Multiple Airlines logo]()
$957
This Icelandair deal was found by Cheapflights users on 7/21. 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 Icelandair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/152:40 pm
STL
- KEF
1 stop10h 55m
Multiple Airlines
Wed 8/265:00 pm
KEF
- STL
1 stop19h 45m
Multiple Airlines
Deal found 7/21![Multiple Airlines logo]()
$857
This FlightHub deal was found by Cheapflights users on 7/20. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/151:04 pm
STL
- KEF
2 stops38h 16m
Scandinavian Airlines
Wed 8/265:35 pm
KEF
- STL
2 stops35h 23m
Scandinavian Airlines
Deal found 7/20![Scandinavian Airlines logo]()
$875
This Icelandair deal was found by Cheapflights users on 7/17. 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 Icelandair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/181:40 pm
STL
- KEF
1 stop11h 45m
Multiple Airlines
Sat 8/2910:45 am
KEF
- STL
1 stop15h 50m
Multiple Airlines
Deal found 7/17![Multiple Airlines logo]()
$917
This Kiwi.com deal was found by Cheapflights users on 7/19. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 8/236:17 pm
STL
- KEF
2 stops30h 43m
Multiple Airlines
Mon 8/3110:45 am
KEF
- STL
1 stop13h 28m
Multiple Airlines
Deal found 7/19![Multiple Airlines logo]()
$783
This Icelandair deal was found by Cheapflights users on 7/20. 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 Icelandair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/243:45 pm
STL
- KEF
1 stop11h 55m
Multiple Airlines
Sat 8/2910:45 am
KEF
- STL
1 stop15h 50m
Multiple Airlines
Deal found 7/20![Multiple Airlines logo]()
$942
One-way flights from St. Louis to Keflavik IntlSearch for one-way flight options from St. Louis to Keflavik Intl. Find affordable one-way fares based on user searches. Data last updated July 22, 2026.
Search for one-way flight options from St. Louis to Keflavik Intl. Find affordable one-way fares based on user searches. Data last updated July 22, 2026.
This Expedia deal was found by Cheapflights users on 7/19. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/2412:10 pm
STL
- KEF
1 stop14h 45m
Air Canada
Deal found 7/19![Air Canada logo]()
$499
This United Airlines deal was found by Cheapflights users on 7/19. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/247:30 am
STL
- KEF
3 stops19h 25m
United Airlines
Deal found 7/19![United Airlines logo]()
$528
Find flight deals from St. Louis to Keflavik Intl
Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to Keflavik Intl (KEF). 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 July 22, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $736 (United Airlines) |
One-way from | $499 (Expedia) |
Cheapflights Fare Finder
Customize your flight search to find flights from St. Louis to Keflavik Intl 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 22, 2026.
Use the filters below to find and compare flights from St. Louis to Reykjavik Keflavik Intl Airport that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
St. LouisReykjavik
STL - KEF
STLKEF
Lambert-St Louis
Mon 9/21
7:00 am-7:00 am
1 stop19h 00m
Reykjavik Keflavik Intl
Wed 9/30
9:15 am-3:43 pm
2 stops35h 28m
$784
St. LouisReykjavik
STL - KEF
STLKEF
Lambert-St Louis
Tue 9/22
12:10 pm-7:55 am
1 stop14h 45m
Reykjavik Keflavik Intl
Tue 9/29
10:00 am-11:22 am
2 stops30h 22m
$788
Quickest round-trip
St. LouisReykjavik
STL - KEF
STLKEF
Lambert-St Louis
Sat 10/10
1:45 pm-6:35 am
1 stop11h 50m
Reykjavik Keflavik Intl
Sat 10/17
7:50 pm-9:20 am
1 stop18h 30m
$863
St. LouisReykjavik
STL - KEF
STLKEF
Lambert-St Louis
Tue 9/1
12:20 pm-6:00 am
1 stop12h 40m
Reykjavik Keflavik Intl
Tue 9/8
4:45 pm-9:30 am
1 stop21h 45m
$899
St. LouisReykjavik
STL - KEF
STLKEF
Lambert-St Louis
Fri 10/9
8:55 am-8:45 am
1 stop18h 50m
Reykjavik Keflavik Intl
Sat 10/17
10:00 am-3:43 pm
2 stops34h 43m
$899
St. LouisReykjavik
STL - KEF
STLKEF
Lambert-St Louis
Sun 9/20
4:20 pm-8:40 am
1 stop11h 20m
Reykjavik Keflavik Intl
Wed 9/30
5:00 pm-7:45 am
1 stop19h 45m
$907
Cheapest one-way
Quickest one-way
St. LouisReykjavik
STL - KEF
STLKEF
Lambert-St Louis
Thu 9/24
12:10 pm-7:55 am
1 stop14h 45m
$499
St. LouisReykjavik
STL - KEF
STLKEF
Lambert-St Louis
Thu 9/24
7:30 am-7:55 am
3 stops19h 25m
$528
Sorted by cheapest first
Compare providers for flights from St. Louis to Keflavik Intl
Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from St. Louis to Keflavik Intl in July.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars |
- Most accurate provider: When it comes to deals on St. Louis-Reykjavik Keflavik Intl Airport flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on St. Louis-Reykjavik Keflavik Intl Airport flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from St. Louis-Reykjavik Keflavik Intl Airport flight searches over the past month and is updated monthly.
- Most trusted provider: When it comes to deals on St. Louis-Reykjavik Keflavik Intl Airport flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for St. Louis-Reykjavik Keflavik Intl Airport flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.
Best time to book a flight from St. Louis to Keflavik Intl
Have a flexible travel schedule? Discover the best time to fly to Keflavik Intl from St. Louis with our price prediction graph.
STL-KEF
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.
Reviews of airlines servicing Keflavik Intl
Get insights into the airlines that provide service to Keflavik Intl. 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 Keflavik Intl. Reviews last updated July 22, 2026.
See what other customers who have flown with KLM,Delta, andUnited Airlines from St. Louis to Reykjavik Keflavik Intl Airport have to say. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Entertainment
7.2
Boarding
7.8
Overall
7.8
Crew
8.4
Food
7.3
Comfort
7.7
Reviews
1 / 20
6.0
GoodAnonymous,Apr 2026
OKC - ATL
Entertainment
7.2
Boarding
7.8
Overall
7.8
Crew
8.4
Food
7.3
Comfort
7.7
Reviews
1 / 20
6.0
GoodAnonymous,Apr 2026
OKC - ATL
Entertainment
7.2
Boarding
7.8
Overall
7.8
Crew
8.4
Food
7.3
Comfort
7.7
Reviews
1 / 20
6.0
GoodAnonymous,Apr 2026
OKC - ATL
Entertainment
7.2
Boarding
7.8
Overall
7.8
Crew
8.4
Food
7.3
Comfort
7.7
Reviews
1 / 20
6.0
GoodAnonymous,Apr 2026
OKC - ATL
Entertainment
7.2
Boarding
7.8
Overall
7.8
Crew
8.4
Food
7.3
Comfort
7.7
Reviews
1 / 20
6.0
GoodAnonymous,Apr 2026
OKC - ATL
Related info for your journey
Find useful and relevant information for your journey from St. Louis to Keflavik Intl. 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 Reykjavik Keflavik Intl Airport?
Book flights to Reykjavik Keflavik Intl Airport if you plan to visit one of these locationsKeflavik
Hveragerdi
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Other flights to Keflavik Intl
Explore flights to Keflavik Intl departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on July 22, 2026.
St. Louis and Keflavik Intl flights
Browse other St. Louis and Keflavik Intl flight options. Last updated on July 22, 2026.
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Top 4 airlines flying from St. Louis to Keflavik Intl
Discover the top 4 airlines that operate flights from St. Louis to Keflavik Intl. 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 22, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$604 | Average$870 | FlexibilityNo cancel fee | On-time67% | |
| Cheapest$756 | Average$1,080 | FlexibilityNo cancel fee | On-time75% | |
| Cheapest$783 | Average$1,131 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$784 | Average$1,080 | FlexibilityNo cancel fee | On-timeN/A |